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SkipSkiff
11-15-2000, 11:03 AM
I have gotten the go ahead from Mrs. Skip to buy myself a table saw under $500. Thus far I have found a Ryobi that seems to be a good deal ( with base, router mount and a few accessories) Does anyone have recommendations for products?
thanks

SkipSkiff
11-15-2000, 11:03 AM
I have gotten the go ahead from Mrs. Skip to buy myself a table saw under $500. Thus far I have found a Ryobi that seems to be a good deal ( with base, router mount and a few accessories) Does anyone have recommendations for products?
thanks

SkipSkiff
11-15-2000, 11:03 AM
I have gotten the go ahead from Mrs. Skip to buy myself a table saw under $500. Thus far I have found a Ryobi that seems to be a good deal ( with base, router mount and a few accessories) Does anyone have recommendations for products?
thanks

Ed Harrow
11-15-2000, 11:48 AM
Consider used equipment. I sold my old tablesaw (an ancient 10" craftsman) to another guy at CTI. He's in love. He did all the stuff that I should have done (new fence, side table, welded the dammn legs and fitted one of those anti-vibration belts). I'm sure he has <$400 invested and he has a saw "With a motor big enough to cut the Queen Mary in two."

I got a Delta Contractor with unifence and 30+" table for about $800. Nice saw, but who got the better deal...

[This message has been edited by Ed Harrow (edited 11-15-2000).]

Ed Harrow
11-15-2000, 11:48 AM
Consider used equipment. I sold my old tablesaw (an ancient 10" craftsman) to another guy at CTI. He's in love. He did all the stuff that I should have done (new fence, side table, welded the dammn legs and fitted one of those anti-vibration belts). I'm sure he has <$400 invested and he has a saw "With a motor big enough to cut the Queen Mary in two."

I got a Delta Contractor with unifence and 30+" table for about $800. Nice saw, but who got the better deal...

[This message has been edited by Ed Harrow (edited 11-15-2000).]

Ed Harrow
11-15-2000, 11:48 AM
Consider used equipment. I sold my old tablesaw (an ancient 10" craftsman) to another guy at CTI. He's in love. He did all the stuff that I should have done (new fence, side table, welded the dammn legs and fitted one of those anti-vibration belts). I'm sure he has <$400 invested and he has a saw "With a motor big enough to cut the Queen Mary in two."

I got a Delta Contractor with unifence and 30+" table for about $800. Nice saw, but who got the better deal...

[This message has been edited by Ed Harrow (edited 11-15-2000).]

McMichael
11-15-2000, 11:57 AM
Check ALL the schools in your area. They usually have top of the line equipment and occasionally sell off equipment when they're ready to get new. Personally, if I
was more interested in boatbuilding than furniture/cabinet making I believe I would wine and dine Mrs. Skip into the best 14" bandsaw I could manage.

McMichael
11-15-2000, 11:57 AM
Check ALL the schools in your area. They usually have top of the line equipment and occasionally sell off equipment when they're ready to get new. Personally, if I
was more interested in boatbuilding than furniture/cabinet making I believe I would wine and dine Mrs. Skip into the best 14" bandsaw I could manage.

McMichael
11-15-2000, 11:57 AM
Check ALL the schools in your area. They usually have top of the line equipment and occasionally sell off equipment when they're ready to get new. Personally, if I
was more interested in boatbuilding than furniture/cabinet making I believe I would wine and dine Mrs. Skip into the best 14" bandsaw I could manage.

bob goeckel
11-15-2000, 12:59 PM
i'll second the bandsaw. i have a tablesaw and a radial arm saw that mostly collect dust and tools and junk. you can do most everything with the band saw.

bob goeckel
11-15-2000, 12:59 PM
i'll second the bandsaw. i have a tablesaw and a radial arm saw that mostly collect dust and tools and junk. you can do most everything with the band saw.

bob goeckel
11-15-2000, 12:59 PM
i'll second the bandsaw. i have a tablesaw and a radial arm saw that mostly collect dust and tools and junk. you can do most everything with the band saw.

NormMessinger
11-15-2000, 01:52 PM
I donno, Doc. I have all three. If I had to part with two I'd give up the radial arm saw and the band saw, in that order. Depends on what kinda work one wants to do I guess.

But that arguement doesn't help Skip choose. I'd go with a contractor type saw, 10", avoiding Ryobi if possible for the money.

A used saw might be good. Mine is a 1949 or so Atlas my dad traded a '27 Dodge and some money for. Ya cant get that much cast iron in a Ryobi or Craftsman.

Let me ask the experts in the Compuserve Woodworking Forum and see what they say.

--Norm

NormMessinger
11-15-2000, 01:52 PM
I donno, Doc. I have all three. If I had to part with two I'd give up the radial arm saw and the band saw, in that order. Depends on what kinda work one wants to do I guess.

But that arguement doesn't help Skip choose. I'd go with a contractor type saw, 10", avoiding Ryobi if possible for the money.

A used saw might be good. Mine is a 1949 or so Atlas my dad traded a '27 Dodge and some money for. Ya cant get that much cast iron in a Ryobi or Craftsman.

Let me ask the experts in the Compuserve Woodworking Forum and see what they say.

--Norm

NormMessinger
11-15-2000, 01:52 PM
I donno, Doc. I have all three. If I had to part with two I'd give up the radial arm saw and the band saw, in that order. Depends on what kinda work one wants to do I guess.

But that arguement doesn't help Skip choose. I'd go with a contractor type saw, 10", avoiding Ryobi if possible for the money.

A used saw might be good. Mine is a 1949 or so Atlas my dad traded a '27 Dodge and some money for. Ya cant get that much cast iron in a Ryobi or Craftsman.

Let me ask the experts in the Compuserve Woodworking Forum and see what they say.

--Norm

SkipSkiff
11-15-2000, 01:59 PM
Thanks thus far guys, for the record I have a great bandsaw already.

SkipSkiff
11-15-2000, 01:59 PM
Thanks thus far guys, for the record I have a great bandsaw already.

SkipSkiff
11-15-2000, 01:59 PM
Thanks thus far guys, for the record I have a great bandsaw already.

Alan D. Hyde
11-15-2000, 02:15 PM
A kind of related comment, reflecting my waste nothing (or pack rat) predelictions:

It's common to see old washers or dryers put out by the road for pick up by the trash people.

Every one I've ever stopped and looked at has had a working electric motor in it, which can be removed and used for lots of different things around the shop. No point letting 'em go to waste. Never hurts to have a few extras, anyway.

Alan

Alan D. Hyde
11-15-2000, 02:15 PM
A kind of related comment, reflecting my waste nothing (or pack rat) predelictions:

It's common to see old washers or dryers put out by the road for pick up by the trash people.

Every one I've ever stopped and looked at has had a working electric motor in it, which can be removed and used for lots of different things around the shop. No point letting 'em go to waste. Never hurts to have a few extras, anyway.

Alan

Alan D. Hyde
11-15-2000, 02:15 PM
A kind of related comment, reflecting my waste nothing (or pack rat) predelictions:

It's common to see old washers or dryers put out by the road for pick up by the trash people.

Every one I've ever stopped and looked at has had a working electric motor in it, which can be removed and used for lots of different things around the shop. No point letting 'em go to waste. Never hurts to have a few extras, anyway.

Alan

John B
11-15-2000, 05:39 PM
Induction motors like you get in Electra beckum/ Metabo are nice to work with. those screaming skull brush motors.....!

John B
11-15-2000, 05:39 PM
Induction motors like you get in Electra beckum/ Metabo are nice to work with. those screaming skull brush motors.....!

John B
11-15-2000, 05:39 PM
Induction motors like you get in Electra beckum/ Metabo are nice to work with. those screaming skull brush motors.....!

Frank Hagan
11-15-2000, 05:42 PM
I bought the JET Contractor's Saw for just under $500 and I'm very happy with it. I think it was $549 with a $50 rebate when I bought it.

Amazon.com bought Tool Crib, a well-known mail order supplier, and they do have free shipping through Christmas on any item over $100. Their price on the saw is $525 with a $25 rebate, so you get it under your $500 limit. Here's the URL for it at Amazon.com:

http://www.amazon.com/exec/obidos/ASIN/B0000223MF/107-2023581-7053357

Another good choice is the Delta, but it is usually $150 to $200 more. I've used both, and I like my Jet better, but it just barely edges out the Delta for me.

Some people also like Grizzly, but I have no hand's on experience with them. They are a little cheaper, though.

My opinion of the Royobi and Ridgid brands are that they contain too many plastic and light-weight parts. The difference between my Jet and my old Craftsman (made by Emerson, who now makes the Ridgid for Home Depot) is huge. I would never go back to a cheaper saw.

(And I'll second Norm's sentiment ... I have a 14" band saw, and it sure is useful. But you'd have a fight to make me give up my tablesaw.)

Frank Hagan
11-15-2000, 05:42 PM
I bought the JET Contractor's Saw for just under $500 and I'm very happy with it. I think it was $549 with a $50 rebate when I bought it.

Amazon.com bought Tool Crib, a well-known mail order supplier, and they do have free shipping through Christmas on any item over $100. Their price on the saw is $525 with a $25 rebate, so you get it under your $500 limit. Here's the URL for it at Amazon.com:

http://www.amazon.com/exec/obidos/ASIN/B0000223MF/107-2023581-7053357

Another good choice is the Delta, but it is usually $150 to $200 more. I've used both, and I like my Jet better, but it just barely edges out the Delta for me.

Some people also like Grizzly, but I have no hand's on experience with them. They are a little cheaper, though.

My opinion of the Royobi and Ridgid brands are that they contain too many plastic and light-weight parts. The difference between my Jet and my old Craftsman (made by Emerson, who now makes the Ridgid for Home Depot) is huge. I would never go back to a cheaper saw.

(And I'll second Norm's sentiment ... I have a 14" band saw, and it sure is useful. But you'd have a fight to make me give up my tablesaw.)

Frank Hagan
11-15-2000, 05:42 PM
I bought the JET Contractor's Saw for just under $500 and I'm very happy with it. I think it was $549 with a $50 rebate when I bought it.

Amazon.com bought Tool Crib, a well-known mail order supplier, and they do have free shipping through Christmas on any item over $100. Their price on the saw is $525 with a $25 rebate, so you get it under your $500 limit. Here's the URL for it at Amazon.com:

http://www.amazon.com/exec/obidos/ASIN/B0000223MF/107-2023581-7053357

Another good choice is the Delta, but it is usually $150 to $200 more. I've used both, and I like my Jet better, but it just barely edges out the Delta for me.

Some people also like Grizzly, but I have no hand's on experience with them. They are a little cheaper, though.

My opinion of the Royobi and Ridgid brands are that they contain too many plastic and light-weight parts. The difference between my Jet and my old Craftsman (made by Emerson, who now makes the Ridgid for Home Depot) is huge. I would never go back to a cheaper saw.

(And I'll second Norm's sentiment ... I have a 14" band saw, and it sure is useful. But you'd have a fight to make me give up my tablesaw.)

Charlie J
11-15-2000, 06:42 PM
I have one Ryobi tool in my shop - and wil not have another - my objection is that the folks in their parts department really don't care if you get any parts or not- I was attempting to order a new belt for a spindle sander and they could care less if I got it or not. Eventually managed to obtain one-finally.

Most of their tools seem to be very lightly built. Of course, I'm in love with my ancient Delta Uni-saw with it's 3 hp motor!!

Charlie J
11-15-2000, 06:42 PM
I have one Ryobi tool in my shop - and wil not have another - my objection is that the folks in their parts department really don't care if you get any parts or not- I was attempting to order a new belt for a spindle sander and they could care less if I got it or not. Eventually managed to obtain one-finally.

Most of their tools seem to be very lightly built. Of course, I'm in love with my ancient Delta Uni-saw with it's 3 hp motor!!

Charlie J
11-15-2000, 06:42 PM
I have one Ryobi tool in my shop - and wil not have another - my objection is that the folks in their parts department really don't care if you get any parts or not- I was attempting to order a new belt for a spindle sander and they could care less if I got it or not. Eventually managed to obtain one-finally.

Most of their tools seem to be very lightly built. Of course, I'm in love with my ancient Delta Uni-saw with it's 3 hp motor!!

bob goeckel
11-15-2000, 07:36 PM
norm, i'd part with my radialarm saw first also. mostly a waste of space. a circular saw can do most of that work.
ps norm, i switched to my given name because another forumite was using "doc" and i didn't want to cause a problem or confusion.

[This message has been edited by bob goeckel (edited 11-15-2000).]

bob goeckel
11-15-2000, 07:36 PM
norm, i'd part with my radialarm saw first also. mostly a waste of space. a circular saw can do most of that work.
ps norm, i switched to my given name because another forumite was using "doc" and i didn't want to cause a problem or confusion.

[This message has been edited by bob goeckel (edited 11-15-2000).]

bob goeckel
11-15-2000, 07:36 PM
norm, i'd part with my radialarm saw first also. mostly a waste of space. a circular saw can do most of that work.
ps norm, i switched to my given name because another forumite was using "doc" and i didn't want to cause a problem or confusion.

[This message has been edited by bob goeckel (edited 11-15-2000).]

RCullison
11-16-2000, 07:24 AM
I bought the ryobi saw last year and have been very happy with it. I could have gotten a saw with a larger table for about the same money but didn't have room in my shop for it. The Ryobi is adjustable enough to allow me to do most of the things a larger saw would do on a smaller storage footprint. If you have the room you would probably find something like a standard Delta, not the contractor size, easier to use. The house brand saws that Home Depot is selling now look like a good buy for the money. One thing to consider is that there are lots of accessories available for a standard Delta type saw while for the most part you are restricted to items specially made for the Ryobi.

RCullison
11-16-2000, 07:24 AM
I bought the ryobi saw last year and have been very happy with it. I could have gotten a saw with a larger table for about the same money but didn't have room in my shop for it. The Ryobi is adjustable enough to allow me to do most of the things a larger saw would do on a smaller storage footprint. If you have the room you would probably find something like a standard Delta, not the contractor size, easier to use. The house brand saws that Home Depot is selling now look like a good buy for the money. One thing to consider is that there are lots of accessories available for a standard Delta type saw while for the most part you are restricted to items specially made for the Ryobi.

RCullison
11-16-2000, 07:24 AM
I bought the ryobi saw last year and have been very happy with it. I could have gotten a saw with a larger table for about the same money but didn't have room in my shop for it. The Ryobi is adjustable enough to allow me to do most of the things a larger saw would do on a smaller storage footprint. If you have the room you would probably find something like a standard Delta, not the contractor size, easier to use. The house brand saws that Home Depot is selling now look like a good buy for the money. One thing to consider is that there are lots of accessories available for a standard Delta type saw while for the most part you are restricted to items specially made for the Ryobi.

Steve McMahon
11-16-2000, 08:44 AM
Fine Homebuilding magazine - I think the last issue - had a comparison of all the popular 10" portable saws. Sorry I don't have the copy anymore because I lent it to distant
friend, but it may still be on the store shelves. FHB is a mag that is second only to WB.

Steve McMahon
11-16-2000, 08:44 AM
Fine Homebuilding magazine - I think the last issue - had a comparison of all the popular 10" portable saws. Sorry I don't have the copy anymore because I lent it to distant
friend, but it may still be on the store shelves. FHB is a mag that is second only to WB.

Steve McMahon
11-16-2000, 08:44 AM
Fine Homebuilding magazine - I think the last issue - had a comparison of all the popular 10" portable saws. Sorry I don't have the copy anymore because I lent it to distant
friend, but it may still be on the store shelves. FHB is a mag that is second only to WB.

ishmael
11-16-2000, 11:23 AM
If you can wait, look used. I saw an old Craftsman 8" (to be any good Craftman have to be old!) just recently advertised for fifty bucks. Can do a great deal of work with an 8 inch.

Going new, the Taiwanese have caught up and sometimes surpassed us in the quality control area. Fifteen years ago, I wouldn't have bought one, but the last I looked they looked as good as all but top of the line Delta.

I've looked at the Ryobi you mention but, never used one. They look nifty and, if not for heavy use, would probably be fine.

Depending on what you're gonna do with it, as mentioned above you might want to consider a bandsaw first. Probably more versatile but, not as good obviously for much ripping or for cabinet work. Good luck.

ishmael
11-16-2000, 11:23 AM
If you can wait, look used. I saw an old Craftsman 8" (to be any good Craftman have to be old!) just recently advertised for fifty bucks. Can do a great deal of work with an 8 inch.

Going new, the Taiwanese have caught up and sometimes surpassed us in the quality control area. Fifteen years ago, I wouldn't have bought one, but the last I looked they looked as good as all but top of the line Delta.

I've looked at the Ryobi you mention but, never used one. They look nifty and, if not for heavy use, would probably be fine.

Depending on what you're gonna do with it, as mentioned above you might want to consider a bandsaw first. Probably more versatile but, not as good obviously for much ripping or for cabinet work. Good luck.

ishmael
11-16-2000, 11:23 AM
If you can wait, look used. I saw an old Craftsman 8" (to be any good Craftman have to be old!) just recently advertised for fifty bucks. Can do a great deal of work with an 8 inch.

Going new, the Taiwanese have caught up and sometimes surpassed us in the quality control area. Fifteen years ago, I wouldn't have bought one, but the last I looked they looked as good as all but top of the line Delta.

I've looked at the Ryobi you mention but, never used one. They look nifty and, if not for heavy use, would probably be fine.

Depending on what you're gonna do with it, as mentioned above you might want to consider a bandsaw first. Probably more versatile but, not as good obviously for much ripping or for cabinet work. Good luck.

Chad Smith
11-16-2000, 11:24 AM
Look in Harbor Freight tools. If you are careful you can find some good deals. They have a 10" Delta for $380. I've seen DeWalt portables new and reconditioned at better than retail prices. They have some tools in there that I wouldn't buy, but if you stick to the name brands there pretty good and any order over $50 shipping is free.
http://www.harborfreight.com

Chad

Chad Smith
11-16-2000, 11:24 AM
Look in Harbor Freight tools. If you are careful you can find some good deals. They have a 10" Delta for $380. I've seen DeWalt portables new and reconditioned at better than retail prices. They have some tools in there that I wouldn't buy, but if you stick to the name brands there pretty good and any order over $50 shipping is free.
http://www.harborfreight.com

Chad

Chad Smith
11-16-2000, 11:24 AM
Look in Harbor Freight tools. If you are careful you can find some good deals. They have a 10" Delta for $380. I've seen DeWalt portables new and reconditioned at better than retail prices. They have some tools in there that I wouldn't buy, but if you stick to the name brands there pretty good and any order over $50 shipping is free.
http://www.harborfreight.com

Chad

McMichael
11-17-2000, 12:17 AM
I've owned a Forrest 40 tooth blade for eight years. Once a year it goes back to New Jersey to be flattened, sharpened, and polished. The charge is $23 up front and if there is any other work done (teeth replaced) they send a bill back with the blade. Square-shooters, always "done me right". As far as Grizzly....
The ONLY tool I purchased and ended up selling with pleasure was a Grizzly 10" disc/ 48" belt combo sander. The damn thing chewed up more belts than a Lab pup.

McMichael
11-17-2000, 12:17 AM
I've owned a Forrest 40 tooth blade for eight years. Once a year it goes back to New Jersey to be flattened, sharpened, and polished. The charge is $23 up front and if there is any other work done (teeth replaced) they send a bill back with the blade. Square-shooters, always "done me right". As far as Grizzly....
The ONLY tool I purchased and ended up selling with pleasure was a Grizzly 10" disc/ 48" belt combo sander. The damn thing chewed up more belts than a Lab pup.

McMichael
11-17-2000, 12:17 AM
I've owned a Forrest 40 tooth blade for eight years. Once a year it goes back to New Jersey to be flattened, sharpened, and polished. The charge is $23 up front and if there is any other work done (teeth replaced) they send a bill back with the blade. Square-shooters, always "done me right". As far as Grizzly....
The ONLY tool I purchased and ended up selling with pleasure was a Grizzly 10" disc/ 48" belt combo sander. The damn thing chewed up more belts than a Lab pup.

Dave Carnell
11-17-2000, 06:58 AM
I grew up with two homemade table saws Dad made. They did a lot of good work, but didn't tilt.

The manufactured saws in the home shop range in the days before WW II were all tilting table; an abominable device.

Right after WW II Sears brought out an 8" tilting arbor table saw for $50 and for another $25 you got a HP motor. That rig served me well until just before 1960 when I bought the Craftsman floor model industrial 10" saw with 1 HP motor for $200. That is a beauty. I added a couple of table extensions and about ten years ago bought a 5 HP motor so I don't getshut down from kicking the thermal switch on the motor any more.

Dave Carnell
11-17-2000, 06:58 AM
I grew up with two homemade table saws Dad made. They did a lot of good work, but didn't tilt.

The manufactured saws in the home shop range in the days before WW II were all tilting table; an abominable device.

Right after WW II Sears brought out an 8" tilting arbor table saw for $50 and for another $25 you got a HP motor. That rig served me well until just before 1960 when I bought the Craftsman floor model industrial 10" saw with 1 HP motor for $200. That is a beauty. I added a couple of table extensions and about ten years ago bought a 5 HP motor so I don't getshut down from kicking the thermal switch on the motor any more.

Dave Carnell
11-17-2000, 06:58 AM
I grew up with two homemade table saws Dad made. They did a lot of good work, but didn't tilt.

The manufactured saws in the home shop range in the days before WW II were all tilting table; an abominable device.

Right after WW II Sears brought out an 8" tilting arbor table saw for $50 and for another $25 you got a HP motor. That rig served me well until just before 1960 when I bought the Craftsman floor model industrial 10" saw with 1 HP motor for $200. That is a beauty. I added a couple of table extensions and about ten years ago bought a 5 HP motor so I don't getshut down from kicking the thermal switch on the motor any more.

Dave R
11-17-2000, 08:47 AM
Dave C--You bring up a question. I'm looking at tablesaws, too. Right now I don't have 220 in my shop er garage and I don't plan on putting it in for a number of reasons. So would it make sense to buy a 1-1/2 hp saw now and upgrade just the motor later when I have my real shop? Or should I just plan on buying another saw at that point? Or should I just wait and get the saw I want when I have the space and power requirements met?

Dave R
11-17-2000, 08:47 AM
Dave C--You bring up a question. I'm looking at tablesaws, too. Right now I don't have 220 in my shop er garage and I don't plan on putting it in for a number of reasons. So would it make sense to buy a 1-1/2 hp saw now and upgrade just the motor later when I have my real shop? Or should I just plan on buying another saw at that point? Or should I just wait and get the saw I want when I have the space and power requirements met?

Dave R
11-17-2000, 08:47 AM
Dave C--You bring up a question. I'm looking at tablesaws, too. Right now I don't have 220 in my shop er garage and I don't plan on putting it in for a number of reasons. So would it make sense to buy a 1-1/2 hp saw now and upgrade just the motor later when I have my real shop? Or should I just plan on buying another saw at that point? Or should I just wait and get the saw I want when I have the space and power requirements met?

Chad Smith
11-17-2000, 10:24 AM
Dave I beleive that most table saws come 110 volts. The big commercial saws are probably 220 volts. In any case most electrical motors can be converted to 220 volts by just a real quick re-wiring on the motor. The data plate should have a re-wiring diagramn. Be advise not all motors are capable of doing this, but most small motors are.

Chad

Chad Smith
11-17-2000, 10:24 AM
Dave I beleive that most table saws come 110 volts. The big commercial saws are probably 220 volts. In any case most electrical motors can be converted to 220 volts by just a real quick re-wiring on the motor. The data plate should have a re-wiring diagramn. Be advise not all motors are capable of doing this, but most small motors are.

Chad

Chad Smith
11-17-2000, 10:24 AM
Dave I beleive that most table saws come 110 volts. The big commercial saws are probably 220 volts. In any case most electrical motors can be converted to 220 volts by just a real quick re-wiring on the motor. The data plate should have a re-wiring diagramn. Be advise not all motors are capable of doing this, but most small motors are.

Chad

Frank Hagan
11-17-2000, 11:20 AM
I'll add another comment on the motor voltage issue. The contractor style saws run fine on 115v, but will trip a 15 amp breaker when they get hot. A 20 amp service is better. On these small motors, 230v is really not much of an advantage until you get into larger sizes. The only difference for the homeowner is that at 230v, a smaller wire size can be used to carry the current needed. But that's offset (usually) by having to install 230v service into the garage.

So, for convenience's sake, I would stick to a 115v, 1 1/2 hp contractor's grade saw for home shop use. If you have to step up to the $1400 cabinet grade saw at 3 hp, you need to go to 230v power.

Frank Hagan
11-17-2000, 11:20 AM
I'll add another comment on the motor voltage issue. The contractor style saws run fine on 115v, but will trip a 15 amp breaker when they get hot. A 20 amp service is better. On these small motors, 230v is really not much of an advantage until you get into larger sizes. The only difference for the homeowner is that at 230v, a smaller wire size can be used to carry the current needed. But that's offset (usually) by having to install 230v service into the garage.

So, for convenience's sake, I would stick to a 115v, 1 1/2 hp contractor's grade saw for home shop use. If you have to step up to the $1400 cabinet grade saw at 3 hp, you need to go to 230v power.

Frank Hagan
11-17-2000, 11:20 AM
I'll add another comment on the motor voltage issue. The contractor style saws run fine on 115v, but will trip a 15 amp breaker when they get hot. A 20 amp service is better. On these small motors, 230v is really not much of an advantage until you get into larger sizes. The only difference for the homeowner is that at 230v, a smaller wire size can be used to carry the current needed. But that's offset (usually) by having to install 230v service into the garage.

So, for convenience's sake, I would stick to a 115v, 1 1/2 hp contractor's grade saw for home shop use. If you have to step up to the $1400 cabinet grade saw at 3 hp, you need to go to 230v power.

Dave R
11-17-2000, 11:27 AM
Gentlemen,
Thank you for your comments. I actually do plan on going to a 3 hp saw once my shop is built. I don't think I'd bother with putting a 3 hp motor on a contractor's swa, though.
Hmm... Maybe I should by a contractor's saw now and a cabinet saw later. I do only have 15A service in my current shop er garage.

Dave R
11-17-2000, 11:27 AM
Gentlemen,
Thank you for your comments. I actually do plan on going to a 3 hp saw once my shop is built. I don't think I'd bother with putting a 3 hp motor on a contractor's swa, though.
Hmm... Maybe I should by a contractor's saw now and a cabinet saw later. I do only have 15A service in my current shop er garage.

Dave R
11-17-2000, 11:27 AM
Gentlemen,
Thank you for your comments. I actually do plan on going to a 3 hp saw once my shop is built. I don't think I'd bother with putting a 3 hp motor on a contractor's swa, though.
Hmm... Maybe I should by a contractor's saw now and a cabinet saw later. I do only have 15A service in my current shop er garage.

Ross Faneuf
11-18-2000, 12:08 PM
I bought a very used Powermatic model 66 more than 20 years ago; it must now be between 30 and 40 years old. As near as I can tell, it's just as good as the day it left the factory. A Delta of the same vintage would be just as good - except, of course, that the blade tilts the wrong way http://media4.hypernet.com/~dick/ubb/smile.gif. Any of these would be minimum 3 hp 240v, and can run for extended periods without overheating. It's worth keeping your eyes open - these machines are so heavily built that you can usually trust a used one as long as it hasn't spent the last year or two out in the rain. I couldn't say whether you'd be lucky enough to find one under $500 though.

[This message has been edited by Ross Faneuf (edited 11-18-2000).]

Ross Faneuf
11-18-2000, 12:08 PM
I bought a very used Powermatic model 66 more than 20 years ago; it must now be between 30 and 40 years old. As near as I can tell, it's just as good as the day it left the factory. A Delta of the same vintage would be just as good - except, of course, that the blade tilts the wrong way http://media4.hypernet.com/~dick/ubb/smile.gif. Any of these would be minimum 3 hp 240v, and can run for extended periods without overheating. It's worth keeping your eyes open - these machines are so heavily built that you can usually trust a used one as long as it hasn't spent the last year or two out in the rain. I couldn't say whether you'd be lucky enough to find one under $500 though.

[This message has been edited by Ross Faneuf (edited 11-18-2000).]

Ross Faneuf
11-18-2000, 12:08 PM
I bought a very used Powermatic model 66 more than 20 years ago; it must now be between 30 and 40 years old. As near as I can tell, it's just as good as the day it left the factory. A Delta of the same vintage would be just as good - except, of course, that the blade tilts the wrong way http://media4.hypernet.com/~dick/ubb/smile.gif. Any of these would be minimum 3 hp 240v, and can run for extended periods without overheating. It's worth keeping your eyes open - these machines are so heavily built that you can usually trust a used one as long as it hasn't spent the last year or two out in the rain. I couldn't say whether you'd be lucky enough to find one under $500 though.

[This message has been edited by Ross Faneuf (edited 11-18-2000).]

Steve McMahon
11-19-2000, 08:20 PM
A minor Correction:
The best motor to get on anything single phase is an Capacitor start / Capacitor run type. The "built in type" are brush type motors - capable of going at higher speeds, cheaper to make, etc. A cap start / cap run motor is an induction motor - the current from the stator induces current into the rotor - therefore no need for brushes to transfer current to the rotor, or armature as it is called in that type of motor. The portable contractor type saws are almost all brush motors, you don't get an induction motor until you get into the heavier saws. The simple reasons are that the brush motors are cheaper and they are lighter. Another thing to look at in a big saw is one that has an 1800 rpm motor - they last a lot longer than a 3600 rpm motor. Single phase induction motors have a rotating switch assembly that wears out. In a higher speed motor they wear out faster. TEFC = Totally enclosed fan cooled - no way for sawdust to get into the windings causing heat retention / burnout. The cheaper tools will have an ODP = open drip proof motor. If you have one of these in anything in your shop you should blow it out with compressed air every so often - otherwise it will fail prematurely and it is also a fire hazard. Also also also - it doesn't matter if you run on 120V or 220V - the torque / efficiency / Hp is exactly the same. The reason saws over 1 1/2 HP are usually hooked up 220V is to to use smaller wire. The motors will draw 1/2 of the current at 220V than they would at 120V. Hense the reason the biggest "normal" saw is 1 1/2HP - a 1 1/2HP single phase motor at 120V draws 15 amps at full load - the limit of a normal household circuit. The numero uno biggest cause of less than expected performance and less than expected life of big electric power tools like table saws, band saws, and air compressors is the undersizing of the feeder cables from the electrical panel to the tool.
For example: you buy a 1 1/2hp tool and the nameplate says 15Amps - so you put in 14 guage wire to the tool. Simple except you have to take into account the voltage drop of the cable. If you have any appreciable distance of wire (like more than 10 or 20 feet!) you MUST oversize it. Voltage drop causes an extreme loss of performance. Assuming the normal situation where you have a shop (your garage) thats say 20-50 feet from your house. The best thing you can do is put a 40Amp two pole breaker in your house panel, and from it run some #8/3conductor cable to your shop to a 12 or 24 circuit panel. In that panel you can put the appropriate breaker for each tools - your welder, air compressor, Table saw, band saw, some split plugs for hand tools, lights, etc.
Very sorry for the tirade, I sell and apply electric motors for a living and the company I work for has a motor repair shop. I have watched for years as guys come in with table saw motors that are fried, or crying about the lack of performance because they were simply running it off of too small of a wire. You can't expect to rip up a bunch of oak ribs for your new boat on a 1 1/2HP table saw that's plugged into your el-cheapo 16 guage 50' extension cord any more than you can run it off of a plug that's in a shop fed with a piece of 14 guage wire that is run 75' to your house panel and also feeds your lights and stuff. Ther. I've said my piece and now I am going to have a little drink of scotch. Make sure you run big enough wire to your big tools. http://media4.hypernet.com/~dick/ubb/smile.gif

Steve McMahon
11-19-2000, 08:20 PM
A minor Correction:
The best motor to get on anything single phase is an Capacitor start / Capacitor run type. The "built in type" are brush type motors - capable of going at higher speeds, cheaper to make, etc. A cap start / cap run motor is an induction motor - the current from the stator induces current into the rotor - therefore no need for brushes to transfer current to the rotor, or armature as it is called in that type of motor. The portable contractor type saws are almost all brush motors, you don't get an induction motor until you get into the heavier saws. The simple reasons are that the brush motors are cheaper and they are lighter. Another thing to look at in a big saw is one that has an 1800 rpm motor - they last a lot longer than a 3600 rpm motor. Single phase induction motors have a rotating switch assembly that wears out. In a higher speed motor they wear out faster. TEFC = Totally enclosed fan cooled - no way for sawdust to get into the windings causing heat retention / burnout. The cheaper tools will have an ODP = open drip proof motor. If you have one of these in anything in your shop you should blow it out with compressed air every so often - otherwise it will fail prematurely and it is also a fire hazard. Also also also - it doesn't matter if you run on 120V or 220V - the torque / efficiency / Hp is exactly the same. The reason saws over 1 1/2 HP are usually hooked up 220V is to to use smaller wire. The motors will draw 1/2 of the current at 220V than they would at 120V. Hense the reason the biggest "normal" saw is 1 1/2HP - a 1 1/2HP single phase motor at 120V draws 15 amps at full load - the limit of a normal household circuit. The numero uno biggest cause of less than expected performance and less than expected life of big electric power tools like table saws, band saws, and air compressors is the undersizing of the feeder cables from the electrical panel to the tool.
For example: you buy a 1 1/2hp tool and the nameplate says 15Amps - so you put in 14 guage wire to the tool. Simple except you have to take into account the voltage drop of the cable. If you have any appreciable distance of wire (like more than 10 or 20 feet!) you MUST oversize it. Voltage drop causes an extreme loss of performance. Assuming the normal situation where you have a shop (your garage) thats say 20-50 feet from your house. The best thing you can do is put a 40Amp two pole breaker in your house panel, and from it run some #8/3conductor cable to your shop to a 12 or 24 circuit panel. In that panel you can put the appropriate breaker for each tools - your welder, air compressor, Table saw, band saw, some split plugs for hand tools, lights, etc.
Very sorry for the tirade, I sell and apply electric motors for a living and the company I work for has a motor repair shop. I have watched for years as guys come in with table saw motors that are fried, or crying about the lack of performance because they were simply running it off of too small of a wire. You can't expect to rip up a bunch of oak ribs for your new boat on a 1 1/2HP table saw that's plugged into your el-cheapo 16 guage 50' extension cord any more than you can run it off of a plug that's in a shop fed with a piece of 14 guage wire that is run 75' to your house panel and also feeds your lights and stuff. Ther. I've said my piece and now I am going to have a little drink of scotch. Make sure you run big enough wire to your big tools. http://media4.hypernet.com/~dick/ubb/smile.gif

Steve McMahon
11-19-2000, 08:20 PM
A minor Correction:
The best motor to get on anything single phase is an Capacitor start / Capacitor run type. The "built in type" are brush type motors - capable of going at higher speeds, cheaper to make, etc. A cap start / cap run motor is an induction motor - the current from the stator induces current into the rotor - therefore no need for brushes to transfer current to the rotor, or armature as it is called in that type of motor. The portable contractor type saws are almost all brush motors, you don't get an induction motor until you get into the heavier saws. The simple reasons are that the brush motors are cheaper and they are lighter. Another thing to look at in a big saw is one that has an 1800 rpm motor - they last a lot longer than a 3600 rpm motor. Single phase induction motors have a rotating switch assembly that wears out. In a higher speed motor they wear out faster. TEFC = Totally enclosed fan cooled - no way for sawdust to get into the windings causing heat retention / burnout. The cheaper tools will have an ODP = open drip proof motor. If you have one of these in anything in your shop you should blow it out with compressed air every so often - otherwise it will fail prematurely and it is also a fire hazard. Also also also - it doesn't matter if you run on 120V or 220V - the torque / efficiency / Hp is exactly the same. The reason saws over 1 1/2 HP are usually hooked up 220V is to to use smaller wire. The motors will draw 1/2 of the current at 220V than they would at 120V. Hense the reason the biggest "normal" saw is 1 1/2HP - a 1 1/2HP single phase motor at 120V draws 15 amps at full load - the limit of a normal household circuit. The numero uno biggest cause of less than expected performance and less than expected life of big electric power tools like table saws, band saws, and air compressors is the undersizing of the feeder cables from the electrical panel to the tool.
For example: you buy a 1 1/2hp tool and the nameplate says 15Amps - so you put in 14 guage wire to the tool. Simple except you have to take into account the voltage drop of the cable. If you have any appreciable distance of wire (like more than 10 or 20 feet!) you MUST oversize it. Voltage drop causes an extreme loss of performance. Assuming the normal situation where you have a shop (your garage) thats say 20-50 feet from your house. The best thing you can do is put a 40Amp two pole breaker in your house panel, and from it run some #8/3conductor cable to your shop to a 12 or 24 circuit panel. In that panel you can put the appropriate breaker for each tools - your welder, air compressor, Table saw, band saw, some split plugs for hand tools, lights, etc.
Very sorry for the tirade, I sell and apply electric motors for a living and the company I work for has a motor repair shop. I have watched for years as guys come in with table saw motors that are fried, or crying about the lack of performance because they were simply running it off of too small of a wire. You can't expect to rip up a bunch of oak ribs for your new boat on a 1 1/2HP table saw that's plugged into your el-cheapo 16 guage 50' extension cord any more than you can run it off of a plug that's in a shop fed with a piece of 14 guage wire that is run 75' to your house panel and also feeds your lights and stuff. Ther. I've said my piece and now I am going to have a little drink of scotch. Make sure you run big enough wire to your big tools. http://media4.hypernet.com/~dick/ubb/smile.gif

abe
11-20-2000, 07:15 AM
Thanks for the "tirade" Steve. I am printing it to hang in the shop. Your info is very timely and helpful. I am adding two more breakers in the shop today, one for a heater and the second for 220v outlet that will feed a future table saw (on the wish list).

Local codes specify EMT for all wiring, and I am near capacity in the 3/4 inch tubing. The local inspector suggests 12 guage wire for the 220 circuit, but your comment supports my view that 14 guage cable is probably sufficient, i.e. less current draw at 220 vs. 120v. What is your opinion on this option?
Thanks again

Abe

abe
11-20-2000, 07:15 AM
Thanks for the "tirade" Steve. I am printing it to hang in the shop. Your info is very timely and helpful. I am adding two more breakers in the shop today, one for a heater and the second for 220v outlet that will feed a future table saw (on the wish list).

Local codes specify EMT for all wiring, and I am near capacity in the 3/4 inch tubing. The local inspector suggests 12 guage wire for the 220 circuit, but your comment supports my view that 14 guage cable is probably sufficient, i.e. less current draw at 220 vs. 120v. What is your opinion on this option?
Thanks again

Abe

abe
11-20-2000, 07:15 AM
Thanks for the "tirade" Steve. I am printing it to hang in the shop. Your info is very timely and helpful. I am adding two more breakers in the shop today, one for a heater and the second for 220v outlet that will feed a future table saw (on the wish list).

Local codes specify EMT for all wiring, and I am near capacity in the 3/4 inch tubing. The local inspector suggests 12 guage wire for the 220 circuit, but your comment supports my view that 14 guage cable is probably sufficient, i.e. less current draw at 220 vs. 120v. What is your opinion on this option?
Thanks again

Abe

Wayne Jeffers
11-20-2000, 08:45 AM
Abe,

The size wire you use depends upon the amount of current you will be drawing throught the circuit. 12 ga wire = 20 amps peak; 14 ga = 15 amps peak. This rule is the same whether you are using a single-pole circuit breaker (115 v.) or a 2-pole breaker (230 v.). DON'T try to use 14 ga. wire with a 30 amp 2-pole breaker or you will start a fire!!!

I'm not sure they even make 15 amp 2-pole circuit breakers.

On a continuous load basis, you should size so that the wire is carrying no more than 80% of the peak capacity. In other words, don't try to pull more than 16 amps running load over a 20 amp circuit. That contractor grade saw pulling 14 amps at 115 v. needs its own 20 amp circuit.

The difference in the cost of the wire is negligible; the breakers are probably exactly the same price.

Regarding EMT: don't stuff it too full of wire. The purpose of the conduit is to provide mechanical protection to the wire, but it also holds in heat. If the EMT is too full of wire, it interferes with the dissipation of heat and there is a chance that you can cause a fire if enough of the wires are pulling a load. Your local building codes may set a limit on the amount of wires per conduit for this reason.

Wayne

Wayne Jeffers
11-20-2000, 08:45 AM
Abe,

The size wire you use depends upon the amount of current you will be drawing throught the circuit. 12 ga wire = 20 amps peak; 14 ga = 15 amps peak. This rule is the same whether you are using a single-pole circuit breaker (115 v.) or a 2-pole breaker (230 v.). DON'T try to use 14 ga. wire with a 30 amp 2-pole breaker or you will start a fire!!!

I'm not sure they even make 15 amp 2-pole circuit breakers.

On a continuous load basis, you should size so that the wire is carrying no more than 80% of the peak capacity. In other words, don't try to pull more than 16 amps running load over a 20 amp circuit. That contractor grade saw pulling 14 amps at 115 v. needs its own 20 amp circuit.

The difference in the cost of the wire is negligible; the breakers are probably exactly the same price.

Regarding EMT: don't stuff it too full of wire. The purpose of the conduit is to provide mechanical protection to the wire, but it also holds in heat. If the EMT is too full of wire, it interferes with the dissipation of heat and there is a chance that you can cause a fire if enough of the wires are pulling a load. Your local building codes may set a limit on the amount of wires per conduit for this reason.

Wayne

Wayne Jeffers
11-20-2000, 08:45 AM
Abe,

The size wire you use depends upon the amount of current you will be drawing throught the circuit. 12 ga wire = 20 amps peak; 14 ga = 15 amps peak. This rule is the same whether you are using a single-pole circuit breaker (115 v.) or a 2-pole breaker (230 v.). DON'T try to use 14 ga. wire with a 30 amp 2-pole breaker or you will start a fire!!!

I'm not sure they even make 15 amp 2-pole circuit breakers.

On a continuous load basis, you should size so that the wire is carrying no more than 80% of the peak capacity. In other words, don't try to pull more than 16 amps running load over a 20 amp circuit. That contractor grade saw pulling 14 amps at 115 v. needs its own 20 amp circuit.

The difference in the cost of the wire is negligible; the breakers are probably exactly the same price.

Regarding EMT: don't stuff it too full of wire. The purpose of the conduit is to provide mechanical protection to the wire, but it also holds in heat. If the EMT is too full of wire, it interferes with the dissipation of heat and there is a chance that you can cause a fire if enough of the wires are pulling a load. Your local building codes may set a limit on the amount of wires per conduit for this reason.

Wayne

Alan D. Hyde
11-20-2000, 01:06 PM
A useful formula is W/V = A (Watts divided by volts equals amps).

A little extra copper is a good thing, whether in wiring your stereo or your shop. Twenty amp circuits and #12 wire should be a minimum. There is no #14 wire in my house or shop. Aluminum wire is a fire hazard and should be replaced.

A home-made extension cord out of #6 or #8 wire is often useful. I used mine yesterday to run a big compressor I'd borrowed.

Alan

[This message has been edited by Alan D. Hyde (edited 11-20-2000).]

Alan D. Hyde
11-20-2000, 01:06 PM
A useful formula is W/V = A (Watts divided by volts equals amps).

A little extra copper is a good thing, whether in wiring your stereo or your shop. Twenty amp circuits and #12 wire should be a minimum. There is no #14 wire in my house or shop. Aluminum wire is a fire hazard and should be replaced.

A home-made extension cord out of #6 or #8 wire is often useful. I used mine yesterday to run a big compressor I'd borrowed.

Alan

[This message has been edited by Alan D. Hyde (edited 11-20-2000).]

Alan D. Hyde
11-20-2000, 01:06 PM
A useful formula is W/V = A (Watts divided by volts equals amps).

A little extra copper is a good thing, whether in wiring your stereo or your shop. Twenty amp circuits and #12 wire should be a minimum. There is no #14 wire in my house or shop. Aluminum wire is a fire hazard and should be replaced.

A home-made extension cord out of #6 or #8 wire is often useful. I used mine yesterday to run a big compressor I'd borrowed.

Alan

[This message has been edited by Alan D. Hyde (edited 11-20-2000).]

Steve McMahon
11-20-2000, 01:16 PM
What wayne said was correct. However the 15A 2P breakers are very much available - they are the common house breaker for split plugs.
An easier to install option to emt is to run BX cable - metal armoured cable. For a reasonable short distance you can run most 2hp motors on 14 guage 3 conductor at 220V. If there is any length to it at all go up to 12/3. Bx cable and the appropriate connectors should be available at most hardware stores.
Oh yeah - another place I see problems : you should shut off the power to your panel after a few months and retighten the screws on the breaker - they will loosen up after the initial tightening once you have run the motor a few times. While your at it stick the screwdriver on the other breakers and tighten them too.

Steve McMahon
11-20-2000, 01:16 PM
What wayne said was correct. However the 15A 2P breakers are very much available - they are the common house breaker for split plugs.
An easier to install option to emt is to run BX cable - metal armoured cable. For a reasonable short distance you can run most 2hp motors on 14 guage 3 conductor at 220V. If there is any length to it at all go up to 12/3. Bx cable and the appropriate connectors should be available at most hardware stores.
Oh yeah - another place I see problems : you should shut off the power to your panel after a few months and retighten the screws on the breaker - they will loosen up after the initial tightening once you have run the motor a few times. While your at it stick the screwdriver on the other breakers and tighten them too.

Steve McMahon
11-20-2000, 01:16 PM
What wayne said was correct. However the 15A 2P breakers are very much available - they are the common house breaker for split plugs.
An easier to install option to emt is to run BX cable - metal armoured cable. For a reasonable short distance you can run most 2hp motors on 14 guage 3 conductor at 220V. If there is any length to it at all go up to 12/3. Bx cable and the appropriate connectors should be available at most hardware stores.
Oh yeah - another place I see problems : you should shut off the power to your panel after a few months and retighten the screws on the breaker - they will loosen up after the initial tightening once you have run the motor a few times. While your at it stick the screwdriver on the other breakers and tighten them too.

abe
11-20-2000, 01:40 PM
Always a wealth of information on this forum.
Thanks everyone.

I was thinking that pulling three 14 gauge wires for the 220 circuit would be sufficient, but why split hairs over this. The difference in the physical size of the wire is not that much, but certainly with 12 gauge the inspector won't hang around as long.

The use of BX cable in this neck of the woods(New Hampshire) is not recommended. Would have made the wiring job much simpler.

abe
11-20-2000, 01:40 PM
Always a wealth of information on this forum.
Thanks everyone.

I was thinking that pulling three 14 gauge wires for the 220 circuit would be sufficient, but why split hairs over this. The difference in the physical size of the wire is not that much, but certainly with 12 gauge the inspector won't hang around as long.

The use of BX cable in this neck of the woods(New Hampshire) is not recommended. Would have made the wiring job much simpler.

abe
11-20-2000, 01:40 PM
Always a wealth of information on this forum.
Thanks everyone.

I was thinking that pulling three 14 gauge wires for the 220 circuit would be sufficient, but why split hairs over this. The difference in the physical size of the wire is not that much, but certainly with 12 gauge the inspector won't hang around as long.

The use of BX cable in this neck of the woods(New Hampshire) is not recommended. Would have made the wiring job much simpler.

Bryan Mehus
11-21-2000, 01:07 AM
I've been watching this forum from the sidelines and seem to learn something everyday(hope some stays in the grey matter)lots of experience and common sense.

Hope I don't come off as an idiot but somethings just stick in your craw, and this thread seems like a good place to air it.

"Horsepower ratings" ever notice how lately you can buy a compressor or table saw, or just about anything with a motor on it, and it will be rated 3 or 5 hp, and it will have a 15 amp plug on it. If it really delivered that kind of horsepower, you could hook a genset to the output shaft and after you got it started pull the plug and plug into the genset..free power!

Please be careful with advice regarding electrical work(including mine), and check into the local electrical codes and practices. For instance in most locales, it is not permitted to have a 20 amp breaker supplying a 15 amp receptacle even if you did run 12 awg.

Thanks for letting me rant, and please keep up the great dialogue.
Bryan

Bryan Mehus
11-21-2000, 01:07 AM
I've been watching this forum from the sidelines and seem to learn something everyday(hope some stays in the grey matter)lots of experience and common sense.

Hope I don't come off as an idiot but somethings just stick in your craw, and this thread seems like a good place to air it.

"Horsepower ratings" ever notice how lately you can buy a compressor or table saw, or just about anything with a motor on it, and it will be rated 3 or 5 hp, and it will have a 15 amp plug on it. If it really delivered that kind of horsepower, you could hook a genset to the output shaft and after you got it started pull the plug and plug into the genset..free power!

Please be careful with advice regarding electrical work(including mine), and check into the local electrical codes and practices. For instance in most locales, it is not permitted to have a 20 amp breaker supplying a 15 amp receptacle even if you did run 12 awg.

Thanks for letting me rant, and please keep up the great dialogue.
Bryan

Bryan Mehus
11-21-2000, 01:07 AM
I've been watching this forum from the sidelines and seem to learn something everyday(hope some stays in the grey matter)lots of experience and common sense.

Hope I don't come off as an idiot but somethings just stick in your craw, and this thread seems like a good place to air it.

"Horsepower ratings" ever notice how lately you can buy a compressor or table saw, or just about anything with a motor on it, and it will be rated 3 or 5 hp, and it will have a 15 amp plug on it. If it really delivered that kind of horsepower, you could hook a genset to the output shaft and after you got it started pull the plug and plug into the genset..free power!

Please be careful with advice regarding electrical work(including mine), and check into the local electrical codes and practices. For instance in most locales, it is not permitted to have a 20 amp breaker supplying a 15 amp receptacle even if you did run 12 awg.

Thanks for letting me rant, and please keep up the great dialogue.
Bryan

Steve McMahon
11-21-2000, 05:37 AM
Bryan: You right.
In no case should one ever put a fuse or breaker in that has a higher current capacity than the wire or the receptacle. The number one purpose of the fuse or breaker is to protect the complete circuit.(wire, connectors, receptacle or fixture) The tool should have it's own overcurrent protection in the form of an ovlerload relay. Regarding HP: Rotten marketing ploy by the manufacturers - Peak HP? Brake HP? Duty Cycle? Service factor? They mix and match words and phrases to suit their purposes.

Steve McMahon
11-21-2000, 05:37 AM
Bryan: You right.
In no case should one ever put a fuse or breaker in that has a higher current capacity than the wire or the receptacle. The number one purpose of the fuse or breaker is to protect the complete circuit.(wire, connectors, receptacle or fixture) The tool should have it's own overcurrent protection in the form of an ovlerload relay. Regarding HP: Rotten marketing ploy by the manufacturers - Peak HP? Brake HP? Duty Cycle? Service factor? They mix and match words and phrases to suit their purposes.

Steve McMahon
11-21-2000, 05:37 AM
Bryan: You right.
In no case should one ever put a fuse or breaker in that has a higher current capacity than the wire or the receptacle. The number one purpose of the fuse or breaker is to protect the complete circuit.(wire, connectors, receptacle or fixture) The tool should have it's own overcurrent protection in the form of an ovlerload relay. Regarding HP: Rotten marketing ploy by the manufacturers - Peak HP? Brake HP? Duty Cycle? Service factor? They mix and match words and phrases to suit their purposes.

Wayne Jeffers
11-21-2000, 11:07 AM
Bryan,

Regarding the HP ratings, I've seen it described as input or theoretical HP vs. output HP, the difference being somthing to do with the efficiency (or inefficiency) of the motor. It seems the output HP is generally about one-half the input (advertised) HP.

My nominally 2 HP table saw, pulling about 14 - 15 amps at 115 v., is really producing only about one true HP, but it does the job.

Wayne

Wayne Jeffers
11-21-2000, 11:07 AM
Bryan,

Regarding the HP ratings, I've seen it described as input or theoretical HP vs. output HP, the difference being somthing to do with the efficiency (or inefficiency) of the motor. It seems the output HP is generally about one-half the input (advertised) HP.

My nominally 2 HP table saw, pulling about 14 - 15 amps at 115 v., is really producing only about one true HP, but it does the job.

Wayne

Wayne Jeffers
11-21-2000, 11:07 AM
Bryan,

Regarding the HP ratings, I've seen it described as input or theoretical HP vs. output HP, the difference being somthing to do with the efficiency (or inefficiency) of the motor. It seems the output HP is generally about one-half the input (advertised) HP.

My nominally 2 HP table saw, pulling about 14 - 15 amps at 115 v., is really producing only about one true HP, but it does the job.

Wayne

Ed Harrow
11-21-2000, 12:20 PM
"you should shut off the power to your panel after a few months and retighten the screws on the breaker". Steve, turning the power off takes away all the excitment, the challenge, the thrill, esp in the summer when you're sweating http://media4.hypernet.com/~dick/ubb/smile.gif

Ed Harrow
11-21-2000, 12:20 PM
"you should shut off the power to your panel after a few months and retighten the screws on the breaker". Steve, turning the power off takes away all the excitment, the challenge, the thrill, esp in the summer when you're sweating http://media4.hypernet.com/~dick/ubb/smile.gif

Ed Harrow
11-21-2000, 12:20 PM
"you should shut off the power to your panel after a few months and retighten the screws on the breaker". Steve, turning the power off takes away all the excitment, the challenge, the thrill, esp in the summer when you're sweating http://media4.hypernet.com/~dick/ubb/smile.gif

Steve McMahon
11-21-2000, 01:55 PM
Ed - I don't always practice what I preech!
I have burn marks on my linesmans pliars to prove it.

Steve McMahon
11-21-2000, 01:55 PM
Ed - I don't always practice what I preech!
I have burn marks on my linesmans pliars to prove it.

Steve McMahon
11-21-2000, 01:55 PM
Ed - I don't always practice what I preech!
I have burn marks on my linesmans pliars to prove it.

Keith Wilson
11-22-2000, 03:25 PM
You can see how much real horsepower any electric device is putting out by checking the current draw. This spec is usually pretty accurate; the manufacturers don't lie about this like they do about HP; not as much advertising value. 1 HP is about 750 watts, give or take, and so a true 1 HP device would draw at least 6.8 amps at 110V. (More, actually, since it isn't 100 percent efficient, and ignoring starting current). So if your "6 HP advertised" shop vac actually draws, say, 8 amps, it's really 1-1/4 HP max, probably less. Efficiency of a halfway decent squirrel-cage motor should be at least 80%.

[This message has been edited by Keith Wilson (edited 11-22-2000).]

Keith Wilson
11-22-2000, 03:25 PM
You can see how much real horsepower any electric device is putting out by checking the current draw. This spec is usually pretty accurate; the manufacturers don't lie about this like they do about HP; not as much advertising value. 1 HP is about 750 watts, give or take, and so a true 1 HP device would draw at least 6.8 amps at 110V. (More, actually, since it isn't 100 percent efficient, and ignoring starting current). So if your "6 HP advertised" shop vac actually draws, say, 8 amps, it's really 1-1/4 HP max, probably less. Efficiency of a halfway decent squirrel-cage motor should be at least 80%.

[This message has been edited by Keith Wilson (edited 11-22-2000).]

Keith Wilson
11-22-2000, 03:25 PM
You can see how much real horsepower any electric device is putting out by checking the current draw. This spec is usually pretty accurate; the manufacturers don't lie about this like they do about HP; not as much advertising value. 1 HP is about 750 watts, give or take, and so a true 1 HP device would draw at least 6.8 amps at 110V. (More, actually, since it isn't 100 percent efficient, and ignoring starting current). So if your "6 HP advertised" shop vac actually draws, say, 8 amps, it's really 1-1/4 HP max, probably less. Efficiency of a halfway decent squirrel-cage motor should be at least 80%.

[This message has been edited by Keith Wilson (edited 11-22-2000).]

Steve McMahon
11-22-2000, 06:00 PM
I did a little more research because of curiosity. I generally stick with three phase motors, but I do get into a bit of single phase stuff. The outragous HP ratings that some manufacturers are giving stuff is simply marketing - What they are talking about is the short time peak HP output. One way of looking at it in laymans terms is that an electric motor doesn't put out HP - It responds to the load. In other words, your tablesaw running without any wood being cut is only drawing the HP or current required to make everything turn (+) what it takes in electricity to magnetize the motor (-) losses. As you load up that motor by shoving through a big honkin piece of wet oak, the current rises to meet the load within the capability of the motor and wiring to handle it. With the new insulation systems used in motors, you can "overload" them for short periods of time without much damage. The limiting factors in practical terms are the overload protector on the motor, and the fuse or circuit breaker. Because of the improved insulation systems in the motors, they have tweaked up the motor's overload protector to handle a bit more short time current. Circuit breakers and time delay fuses allready have a trip curve that will handle the short time overcurrents.( trip curve = how much time it will take at what current to trip that breaker or burn that fuse, a 15 Amp breaker will supply 15 Amps continuous, about 20 amps for 10 seconds, 25 Amps for 3 seconds etc...) If you don't yet feel confused enough, another way of looking at it is that a motor is a "time rated thermal device" - in other words if it gets too hot for too long it will burn up. (you'll let the smoke out of it) We commonly apply motors where we draw more current / demand more HP out of them by providing auxillary cooling in one form or another. Usually it is in the form of a blower. An extreme example of this is some motors we supplied for a SCARAB undersea remote vehical: the propulsion motors used were 10HP submersible pump motors. In their application where they were submerged in very cold seawater they could safely provide close to 100HP for their short duty cycle.

Another issue I can't let go unanswered is Efficiency. Don't get hung up on it and buy a "high efficiency" motor. Like anything else the design of an electric motor is a series of compramises: Cost/Efficiency/Torque/Ease of manufacturing/Size/Durability/Etc... When you adjust any one of those factors you affect the rest. Usually, the quest for efficiency has resulted in the reduction of torque and loss of durability. It's one thing to look at efficiency for the motor you put on your air handling system that runs 24hrs/day and is an easy load for a motor, but on your tools you want TORQUE and DURABILITY. So what if you burn an extra few bucks worth of electricity, you don't want it to stall and you don't want the bearings to fry. The best all round bet for a machine that takes a electric motor of a common frame size is to go with a "farm duty" motor. They are designed to be abused and they produce grunt torque. If you're in North America go with a NA made brand like Leeson, Doer, Baldor etc. In The UK maybe Hawker Siddely, In Japan or China maybe Toshiba. In Brazil use Weg. If you live anywhere else I havn't got a clue what's best.
Oops, I think I just ranted again. Sorry.

Steve McMahon
11-22-2000, 06:00 PM
I did a little more research because of curiosity. I generally stick with three phase motors, but I do get into a bit of single phase stuff. The outragous HP ratings that some manufacturers are giving stuff is simply marketing - What they are talking about is the short time peak HP output. One way of looking at it in laymans terms is that an electric motor doesn't put out HP - It responds to the load. In other words, your tablesaw running without any wood being cut is only drawing the HP or current required to make everything turn (+) what it takes in electricity to magnetize the motor (-) losses. As you load up that motor by shoving through a big honkin piece of wet oak, the current rises to meet the load within the capability of the motor and wiring to handle it. With the new insulation systems used in motors, you can "overload" them for short periods of time without much damage. The limiting factors in practical terms are the overload protector on the motor, and the fuse or circuit breaker. Because of the improved insulation systems in the motors, they have tweaked up the motor's overload protector to handle a bit more short time current. Circuit breakers and time delay fuses allready have a trip curve that will handle the short time overcurrents.( trip curve = how much time it will take at what current to trip that breaker or burn that fuse, a 15 Amp breaker will supply 15 Amps continuous, about 20 amps for 10 seconds, 25 Amps for 3 seconds etc...) If you don't yet feel confused enough, another way of looking at it is that a motor is a "time rated thermal device" - in other words if it gets too hot for too long it will burn up. (you'll let the smoke out of it) We commonly apply motors where we draw more current / demand more HP out of them by providing auxillary cooling in one form or another. Usually it is in the form of a blower. An extreme example of this is some motors we supplied for a SCARAB undersea remote vehical: the propulsion motors used were 10HP submersible pump motors. In their application where they were submerged in very cold seawater they could safely provide close to 100HP for their short duty cycle.

Another issue I can't let go unanswered is Efficiency. Don't get hung up on it and buy a "high efficiency" motor. Like anything else the design of an electric motor is a series of compramises: Cost/Efficiency/Torque/Ease of manufacturing/Size/Durability/Etc... When you adjust any one of those factors you affect the rest. Usually, the quest for efficiency has resulted in the reduction of torque and loss of durability. It's one thing to look at efficiency for the motor you put on your air handling system that runs 24hrs/day and is an easy load for a motor, but on your tools you want TORQUE and DURABILITY. So what if you burn an extra few bucks worth of electricity, you don't want it to stall and you don't want the bearings to fry. The best all round bet for a machine that takes a electric motor of a common frame size is to go with a "farm duty" motor. They are designed to be abused and they produce grunt torque. If you're in North America go with a NA made brand like Leeson, Doer, Baldor etc. In The UK maybe Hawker Siddely, In Japan or China maybe Toshiba. In Brazil use Weg. If you live anywhere else I havn't got a clue what's best.
Oops, I think I just ranted again. Sorry.

Steve McMahon
11-22-2000, 06:00 PM
I did a little more research because of curiosity. I generally stick with three phase motors, but I do get into a bit of single phase stuff. The outragous HP ratings that some manufacturers are giving stuff is simply marketing - What they are talking about is the short time peak HP output. One way of looking at it in laymans terms is that an electric motor doesn't put out HP - It responds to the load. In other words, your tablesaw running without any wood being cut is only drawing the HP or current required to make everything turn (+) what it takes in electricity to magnetize the motor (-) losses. As you load up that motor by shoving through a big honkin piece of wet oak, the current rises to meet the load within the capability of the motor and wiring to handle it. With the new insulation systems used in motors, you can "overload" them for short periods of time without much damage. The limiting factors in practical terms are the overload protector on the motor, and the fuse or circuit breaker. Because of the improved insulation systems in the motors, they have tweaked up the motor's overload protector to handle a bit more short time current. Circuit breakers and time delay fuses allready have a trip curve that will handle the short time overcurrents.( trip curve = how much time it will take at what current to trip that breaker or burn that fuse, a 15 Amp breaker will supply 15 Amps continuous, about 20 amps for 10 seconds, 25 Amps for 3 seconds etc...) If you don't yet feel confused enough, another way of looking at it is that a motor is a "time rated thermal device" - in other words if it gets too hot for too long it will burn up. (you'll let the smoke out of it) We commonly apply motors where we draw more current / demand more HP out of them by providing auxillary cooling in one form or another. Usually it is in the form of a blower. An extreme example of this is some motors we supplied for a SCARAB undersea remote vehical: the propulsion motors used were 10HP submersible pump motors. In their application where they were submerged in very cold seawater they could safely provide close to 100HP for their short duty cycle.

Another issue I can't let go unanswered is Efficiency. Don't get hung up on it and buy a "high efficiency" motor. Like anything else the design of an electric motor is a series of compramises: Cost/Efficiency/Torque/Ease of manufacturing/Size/Durability/Etc... When you adjust any one of those factors you affect the rest. Usually, the quest for efficiency has resulted in the reduction of torque and loss of durability. It's one thing to look at efficiency for the motor you put on your air handling system that runs 24hrs/day and is an easy load for a motor, but on your tools you want TORQUE and DURABILITY. So what if you burn an extra few bucks worth of electricity, you don't want it to stall and you don't want the bearings to fry. The best all round bet for a machine that takes a electric motor of a common frame size is to go with a "farm duty" motor. They are designed to be abused and they produce grunt torque. If you're in North America go with a NA made brand like Leeson, Doer, Baldor etc. In The UK maybe Hawker Siddely, In Japan or China maybe Toshiba. In Brazil use Weg. If you live anywhere else I havn't got a clue what's best.
Oops, I think I just ranted again. Sorry.

Bryan Mehus
11-26-2000, 01:03 AM
Rick, do you have a make and model# for the inverter?
Quite a few machines are coming out with these types of converters now because of big improvements in power semiconductors. They convert the single phase current into D.C. then fire off transistors at appropriate times to simulate 3 sin waves 120 degrees apart.
Depending on the motor(bearing construction,insulation class etc.)you can run faster than synchronous by 50% or so at a loss of torque, or slow it right down(check the current)to 25% or so. Remember that at the slower speed there is less windage and the motor may overheat at less than fla.
Try to find some info on the drive if you can.
Regards,
Bryan

Bryan Mehus
11-26-2000, 01:03 AM
Rick, do you have a make and model# for the inverter?
Quite a few machines are coming out with these types of converters now because of big improvements in power semiconductors. They convert the single phase current into D.C. then fire off transistors at appropriate times to simulate 3 sin waves 120 degrees apart.
Depending on the motor(bearing construction,insulation class etc.)you can run faster than synchronous by 50% or so at a loss of torque, or slow it right down(check the current)to 25% or so. Remember that at the slower speed there is less windage and the motor may overheat at less than fla.
Try to find some info on the drive if you can.
Regards,
Bryan

Bryan Mehus
11-26-2000, 01:03 AM
Rick, do you have a make and model# for the inverter?
Quite a few machines are coming out with these types of converters now because of big improvements in power semiconductors. They convert the single phase current into D.C. then fire off transistors at appropriate times to simulate 3 sin waves 120 degrees apart.
Depending on the motor(bearing construction,insulation class etc.)you can run faster than synchronous by 50% or so at a loss of torque, or slow it right down(check the current)to 25% or so. Remember that at the slower speed there is less windage and the motor may overheat at less than fla.
Try to find some info on the drive if you can.
Regards,
Bryan

Steve McMahon
11-27-2000, 12:39 PM
Yup. I put an inverter on the blower on my wood furnace, and am setting one up for running a variety of my tools - band saw, table saw, drill press. Actually you get (a lot) better efficiency using an inverter and a three phase motor than you would if you used a single phase motor. It is the wave of the future - If you look to the more advanced places like japan - a typical fridge has three inverters, another on the washing machine, another on the dryer, another on the dishwasher... get my point? Those guys over there sure are smart! The point's mentioned are correct. If you run it to slow, the motor will overheat unless it has auxillary cooling. As you run it over 60hz you start to loose torque because the volts/hz ratio that the inverter puts out degrades (vrs what the motor was designed for.) Let us know the make and specs on R2D2 and We'll be able to help more. BTW my scheme is to put 3 phase motors on all of my fixed tools with a twist lock plug to be able to plug into one inverter. I can only operate one machine at a time so the moment it takes to unplug the band saw from the inverter and plug in the drill press or whatever is minor. The inverter is the expensive item.
Cheers - Steve

Steve McMahon
11-27-2000, 12:39 PM
Yup. I put an inverter on the blower on my wood furnace, and am setting one up for running a variety of my tools - band saw, table saw, drill press. Actually you get (a lot) better efficiency using an inverter and a three phase motor than you would if you used a single phase motor. It is the wave of the future - If you look to the more advanced places like japan - a typical fridge has three inverters, another on the washing machine, another on the dryer, another on the dishwasher... get my point? Those guys over there sure are smart! The point's mentioned are correct. If you run it to slow, the motor will overheat unless it has auxillary cooling. As you run it over 60hz you start to loose torque because the volts/hz ratio that the inverter puts out degrades (vrs what the motor was designed for.) Let us know the make and specs on R2D2 and We'll be able to help more. BTW my scheme is to put 3 phase motors on all of my fixed tools with a twist lock plug to be able to plug into one inverter. I can only operate one machine at a time so the moment it takes to unplug the band saw from the inverter and plug in the drill press or whatever is minor. The inverter is the expensive item.
Cheers - Steve

Steve McMahon
11-27-2000, 12:39 PM
Yup. I put an inverter on the blower on my wood furnace, and am setting one up for running a variety of my tools - band saw, table saw, drill press. Actually you get (a lot) better efficiency using an inverter and a three phase motor than you would if you used a single phase motor. It is the wave of the future - If you look to the more advanced places like japan - a typical fridge has three inverters, another on the washing machine, another on the dryer, another on the dishwasher... get my point? Those guys over there sure are smart! The point's mentioned are correct. If you run it to slow, the motor will overheat unless it has auxillary cooling. As you run it over 60hz you start to loose torque because the volts/hz ratio that the inverter puts out degrades (vrs what the motor was designed for.) Let us know the make and specs on R2D2 and We'll be able to help more. BTW my scheme is to put 3 phase motors on all of my fixed tools with a twist lock plug to be able to plug into one inverter. I can only operate one machine at a time so the moment it takes to unplug the band saw from the inverter and plug in the drill press or whatever is minor. The inverter is the expensive item.
Cheers - Steve

Rick Starr
11-27-2000, 01:51 PM
Thanks Bryan and Steve, I'll look up the deets tomorrow at the shop. It's French, and it's standard equipment on a General #260 lathe. It has a 8.5' bed with 20" swing, which I've maxed out a time or two, and the motor was well up to the job. More tomorrow.

Cheers,
Rick

Rick Starr
11-27-2000, 01:51 PM
Thanks Bryan and Steve, I'll look up the deets tomorrow at the shop. It's French, and it's standard equipment on a General #260 lathe. It has a 8.5' bed with 20" swing, which I've maxed out a time or two, and the motor was well up to the job. More tomorrow.

Cheers,
Rick

Rick Starr
11-27-2000, 01:51 PM
Thanks Bryan and Steve, I'll look up the deets tomorrow at the shop. It's French, and it's standard equipment on a General #260 lathe. It has a 8.5' bed with 20" swing, which I've maxed out a time or two, and the motor was well up to the job. More tomorrow.

Cheers,
Rick

Rick Starr
11-28-2000, 07:03 AM
Ok it's an 'ALTIVAR 16' from 'Telemecanique, Groupe Schneider'
Ref #ATV-16 U18M2
208/240v +/-10%
50-60hz+/-2hz
rated for 1hp
Line current 7A
Speed control rated current 4A
Maximum transient current 5.4A
Total power dissipated at rated load 35W

plus all sorts of stuff about accelleration and decelleration ramps, low speed braking and so on.

All I can say is it really works well, and that despite my fear of electronic boxes with digital readouts and stuff getting corroded and going bad here in the tropics, it seems fine.

TIA

Rick Starr
11-28-2000, 07:03 AM
Ok it's an 'ALTIVAR 16' from 'Telemecanique, Groupe Schneider'
Ref #ATV-16 U18M2
208/240v +/-10%
50-60hz+/-2hz
rated for 1hp
Line current 7A
Speed control rated current 4A
Maximum transient current 5.4A
Total power dissipated at rated load 35W

plus all sorts of stuff about accelleration and decelleration ramps, low speed braking and so on.

All I can say is it really works well, and that despite my fear of electronic boxes with digital readouts and stuff getting corroded and going bad here in the tropics, it seems fine.

TIA

Rick Starr
11-28-2000, 07:03 AM
Ok it's an 'ALTIVAR 16' from 'Telemecanique, Groupe Schneider'
Ref #ATV-16 U18M2
208/240v +/-10%
50-60hz+/-2hz
rated for 1hp
Line current 7A
Speed control rated current 4A
Maximum transient current 5.4A
Total power dissipated at rated load 35W

plus all sorts of stuff about accelleration and decelleration ramps, low speed braking and so on.

All I can say is it really works well, and that despite my fear of electronic boxes with digital readouts and stuff getting corroded and going bad here in the tropics, it seems fine.

TIA

Steve McMahon
11-28-2000, 10:50 AM
Rick
I am only a little familiar with that model. The brand is good. I looked at their web site, buy the Altivar 16 is no longer listed - It's now been replaced with an inverter I am very familiar with because the company I work for makes them and brand labels them. I think the '16 is a constant torque unit, meaning that the torque is directly proportional to the speed. Just don't go too slow for very heavy work or the motor will overheat from lack of cooling from it's own shaft mounted fan. Other than that just keep the dust out of it and the motor (give a shot of dry compressed air if you have it), and maybe once every year or so shut off the power and tighten the terminals. Have fun. An inverter and a three phase motor is a perfect set up for variable speed on a machine.

Steve McMahon
11-28-2000, 10:50 AM
Rick
I am only a little familiar with that model. The brand is good. I looked at their web site, buy the Altivar 16 is no longer listed - It's now been replaced with an inverter I am very familiar with because the company I work for makes them and brand labels them. I think the '16 is a constant torque unit, meaning that the torque is directly proportional to the speed. Just don't go too slow for very heavy work or the motor will overheat from lack of cooling from it's own shaft mounted fan. Other than that just keep the dust out of it and the motor (give a shot of dry compressed air if you have it), and maybe once every year or so shut off the power and tighten the terminals. Have fun. An inverter and a three phase motor is a perfect set up for variable speed on a machine.

Steve McMahon
11-28-2000, 10:50 AM
Rick
I am only a little familiar with that model. The brand is good. I looked at their web site, buy the Altivar 16 is no longer listed - It's now been replaced with an inverter I am very familiar with because the company I work for makes them and brand labels them. I think the '16 is a constant torque unit, meaning that the torque is directly proportional to the speed. Just don't go too slow for very heavy work or the motor will overheat from lack of cooling from it's own shaft mounted fan. Other than that just keep the dust out of it and the motor (give a shot of dry compressed air if you have it), and maybe once every year or so shut off the power and tighten the terminals. Have fun. An inverter and a three phase motor is a perfect set up for variable speed on a machine.

Steve McMahon
12-01-2000, 05:44 AM
Anytime Rick. It was neat that someone asked a question about something I actually have some knowledge in and I can respond with fact instead of opinion. It also helps me avoid the highly addictive Physco (Misc) section of the forum http://media4.hypernet.com/~dick/ubb/smile.gif

Steve McMahon
12-01-2000, 05:44 AM
Anytime Rick. It was neat that someone asked a question about something I actually have some knowledge in and I can respond with fact instead of opinion. It also helps me avoid the highly addictive Physco (Misc) section of the forum http://media4.hypernet.com/~dick/ubb/smile.gif

Steve McMahon
12-01-2000, 05:44 AM
Anytime Rick. It was neat that someone asked a question about something I actually have some knowledge in and I can respond with fact instead of opinion. It also helps me avoid the highly addictive Physco (Misc) section of the forum http://media4.hypernet.com/~dick/ubb/smile.gif

Ron Williamson
12-02-2000, 08:28 PM
OK Steve,could you please explain why some of my electric motors are so much bigger than others.e.g.7.5h.p. 600volt motor is about 8"dia. but a 5h.p.600v is about 11"dia.
The 7.5 is newer but not much.These are both TEFC motors with external fins.

Ron Williamson
12-02-2000, 08:28 PM
OK Steve,could you please explain why some of my electric motors are so much bigger than others.e.g.7.5h.p. 600volt motor is about 8"dia. but a 5h.p.600v is about 11"dia.
The 7.5 is newer but not much.These are both TEFC motors with external fins.

Ron Williamson
12-02-2000, 08:28 PM
OK Steve,could you please explain why some of my electric motors are so much bigger than others.e.g.7.5h.p. 600volt motor is about 8"dia. but a 5h.p.600v is about 11"dia.
The 7.5 is newer but not much.These are both TEFC motors with external fins.

Bryan Mehus
12-08-2000, 11:56 PM
Ron,
A number of things affect the physical size of the motors. The first thing that comes to mind is the number of poles, i.e. the synchronous speed of the motor. Are they both the same? IEC motors are generally smaller than their NEMA counterparts due to manufacturing standards. And a couple of other things that aren't popping into my mind yet. I'll try to think of them.
Bryan

Thanks Steve,I figured you would come through with more complete answer. BTW we use Toshiba, but mostly Seimens. Quite similar in longevity.

[This message has been edited by Bryan Mehus (edited 12-09-2000).]

Bryan Mehus
12-08-2000, 11:56 PM
Ron,
A number of things affect the physical size of the motors. The first thing that comes to mind is the number of poles, i.e. the synchronous speed of the motor. Are they both the same? IEC motors are generally smaller than their NEMA counterparts due to manufacturing standards. And a couple of other things that aren't popping into my mind yet. I'll try to think of them.
Bryan

Thanks Steve,I figured you would come through with more complete answer. BTW we use Toshiba, but mostly Seimens. Quite similar in longevity.

[This message has been edited by Bryan Mehus (edited 12-09-2000).]

Bryan Mehus
12-08-2000, 11:56 PM
Ron,
A number of things affect the physical size of the motors. The first thing that comes to mind is the number of poles, i.e. the synchronous speed of the motor. Are they both the same? IEC motors are generally smaller than their NEMA counterparts due to manufacturing standards. And a couple of other things that aren't popping into my mind yet. I'll try to think of them.
Bryan

Thanks Steve,I figured you would come through with more complete answer. BTW we use Toshiba, but mostly Seimens. Quite similar in longevity.

[This message has been edited by Bryan Mehus (edited 12-09-2000).]

Steve McMahon
12-09-2000, 09:31 AM
Yup, What Bryan said.
The higher the speed of the motor the smaller it is, with the 2pole (3600rpm) motors being the smallest. The IEC (metric) motors are smaller still because their design is maxed - they have much tighter power supply specs in Europe. Our NEMA motors are bigger because they are designed to produce more torque, and to operate on a fluky power system. You can quickly tell if its a NEMA motor by looking at the frame size: If it has a "T" at the end of the numbers then it is a modern Nema design. ie : Frame 184T for a 5hp 1800rpm motor. The only exception is the small motors are typically 48 or 56 frames. The metric frames Go 56, 63, 71, 80, 90, 100, 112, 132 and on and on with either a M,S, or Lat the end : ie 132L. With NEMA frames the first two digits designate shaft height in quarters of an inch : 184T = 4.5" . With Metric the frame number indicates shaft height in MM : 132L = 132MM. About the best NEMA motors on the market that I have ever seen are TOSHIBA - made in Houston Tx.

Steve McMahon
12-09-2000, 09:31 AM
Yup, What Bryan said.
The higher the speed of the motor the smaller it is, with the 2pole (3600rpm) motors being the smallest. The IEC (metric) motors are smaller still because their design is maxed - they have much tighter power supply specs in Europe. Our NEMA motors are bigger because they are designed to produce more torque, and to operate on a fluky power system. You can quickly tell if its a NEMA motor by looking at the frame size: If it has a "T" at the end of the numbers then it is a modern Nema design. ie : Frame 184T for a 5hp 1800rpm motor. The only exception is the small motors are typically 48 or 56 frames. The metric frames Go 56, 63, 71, 80, 90, 100, 112, 132 and on and on with either a M,S, or Lat the end : ie 132L. With NEMA frames the first two digits designate shaft height in quarters of an inch : 184T = 4.5" . With Metric the frame number indicates shaft height in MM : 132L = 132MM. About the best NEMA motors on the market that I have ever seen are TOSHIBA - made in Houston Tx.

Steve McMahon
12-09-2000, 09:31 AM
Yup, What Bryan said.
The higher the speed of the motor the smaller it is, with the 2pole (3600rpm) motors being the smallest. The IEC (metric) motors are smaller still because their design is maxed - they have much tighter power supply specs in Europe. Our NEMA motors are bigger because they are designed to produce more torque, and to operate on a fluky power system. You can quickly tell if its a NEMA motor by looking at the frame size: If it has a "T" at the end of the numbers then it is a modern Nema design. ie : Frame 184T for a 5hp 1800rpm motor. The only exception is the small motors are typically 48 or 56 frames. The metric frames Go 56, 63, 71, 80, 90, 100, 112, 132 and on and on with either a M,S, or Lat the end : ie 132L. With NEMA frames the first two digits designate shaft height in quarters of an inch : 184T = 4.5" . With Metric the frame number indicates shaft height in MM : 132L = 132MM. About the best NEMA motors on the market that I have ever seen are TOSHIBA - made in Houston Tx.

Ron Williamson
12-12-2000, 08:57 PM
Thanks guys
The motors in question are as you say 1800 and 3250RPM.I always thought that the frame size involved the mounting plate.
The reason for the question is an overpowered shaper and an underpowered dust collector.I was thinking about a little swap but space won't allow it.

Ron Williamson
12-12-2000, 08:57 PM
Thanks guys
The motors in question are as you say 1800 and 3250RPM.I always thought that the frame size involved the mounting plate.
The reason for the question is an overpowered shaper and an underpowered dust collector.I was thinking about a little swap but space won't allow it.

Ron Williamson
12-12-2000, 08:57 PM
Thanks guys
The motors in question are as you say 1800 and 3250RPM.I always thought that the frame size involved the mounting plate.
The reason for the question is an overpowered shaper and an underpowered dust collector.I was thinking about a little swap but space won't allow it.