Spring Clamp Wisdom

[Chip-skiff]

I need to buy spring clamps, specifically to set the rubrails and sheer clamps on a 13-1/2 ft. stitch & glue plywood and epoxy skiff.

So first, what spacing of clamps do you recommend for the above job (e.g. every 6 inches)?

And second, is there a particular make (and supplier) that's good without being priced over the moon?

thanks,
Chip

[JimConlin]

6" sounds about right, but if the squeeze-out is uneven, reduce that.

My favorite clamp for that job is this one
http://us.st11.yimg.com/us.st.yimg.com/I/tylertool_1992_238942309
and these folks offer a good price for 'em.
http://us.st11.yimg.com/us.st.yimg.com/I/tylertool_1992_238942309
So good, I just ordered twenty.

[MiddleAgesMan]

The green ones from Home Depot have been added as I needed them. They're about half the price of the orange name brand ones and they have stronger springs--not always better but certainly stronger. In the early building stages I was buying a dozen or so of them every trip for something else. I now have enough to do one side of a Goat Island Skiff at a time (just a little longer than your design).

As for the spacing I never worried about it--clamp on the piece and eyeball it. If there are gaps put in another clamp. If it lays nice and firm in contact with whatever, move along.

[Brian Palmer]

You can inexpensively make your own for that sort of thing out of 4 inch PVC pipe cut into 1-inch wide sections and then slit to form a C-clamp. They work very well with epoxy, maybe not enough pressure for other types of glues. I used them building a small canoe to glue the laps and the rails, as you described.

Brian

[Bill R]

Ditto the Home Depot green spring clamps. $0.99 each locally. For a long time, I would buy 6-12 atr a time while in there for something else just for the rubrails on my ply and goop skiff.

[David G]

I've never used the HD green ones. Have some of the Jorgensen orange ones that I bought used as early as 1972. Still going strong.

As a professional woodworker, it makes sense for me to buy the best. For occasional users, the decision making parameters are a bit different. You have to take into consideration how often you imagine yourself using these tools, and how flush you are, and what it's worth to work with a tool that works and always will vs. one that might not work as well or as long, and whether you want to be able to pass on some quality tools to the next generation.

I think you can see where my bias lies. The PVC pipe version works quite well for gluing on gunwales, etc. with epoxy. They'll eventually break, but are cheap enough to replace easily. The off-brands vary in quality/longevity, but will probably work for the occasional project. If you're in it for the long haul, or just like using tools you don't have to fuss with or worry about - buy a quality brand: Jorgensen, Bessey, et.al.

"The safest course is to do nothing against one conscience. With this secret, we can enjoy life and have no fear from death" -- Voltaire

[Alexander2]

For occasional use the best value in clamps I've found is at Harbor Freight.
Almost everything they have goes on sale several times a year so if the regular low price doesn't suit you they will be cheaper someday.

Heres some on the net, I've seen other ones in the store.

http://search.harborfreight.com/cpisearch/web/search.do?keyword=spring+clamp

[Canoez]

For occasional use the best value in clamps I've found is at Harbor Freight.
Almost everything they have goes on sale several times a year so if the regular low price doesn't suit you they will be cheaper someday.

Heres some on the net, I've seen other ones in the store.

http://search.harborfreight.com/cpisearch/web/search.do?keyword=spring+clamp

I like the Jorgensen spring clamps and have had a few other plastic spring-jaw clamps that have worked well. The ones from Harbor Freight can be a good value, but pay attention to the swivel pads. Some don't have any "limits" so the pads are always swinging so far out and so freely that you're using the edge of the pads, not the faces and it's always when you're doing something awkward and don't have a free hand to re-position the pads.

Inexpensive tools don't cost much money. Cheap tools cost a fortune.

[Chip-skiff]

Right! Thanks for the comments.

I live out in the wop-wops (nearest Home Depot is 100+ miles). So I need to buy enough clamps to do the job with no last-minute shortages.

I've built all manner of weird stuff out of PVC and will try that for reference. But I'll probably end up spending a bit to avoid making 30+ clamps.

Although I've done quite a lot of woodworking I've not used spring clamps in a regular way. So I was wondering about the plain metal ones (e.g. Jorgenson) vs. the plastic ones with swivel clamp faces, adjustable tension, and that sort of stuff.

Chip

[David G]

Chip - this is one area where I'd vote for Simple & Stout.

[Alexander2]

Inexpensive tools don't cost much money. Cheap tools cost a fortune.

Good advice and quite true. Well worth considering.
If it breaks and that will cost me money or valuable time I buy the best I can justify.
If its likely to get lost, abused or used only a few times and failure cost is not an issue I buy cheap.

As a consultant I know sometime says when I ask his advice," Well, that depends...." :)
We are all lucky to have this great place to get advice from all angles.
Good luck with your project.

[StevenBauer]

But I'll probably end up spending a bit to avoid making 30+ clamps.


Chip

Chip, 30 pvc clamps would only take about ten minutes to make if you have a miter saw or a bandsaw. I've had the cheap plastic spring clamps break many times. You come back later and it's on the floor in pieces.

http://www.hanalima.com/images/tips_pvcclamp2.gif

You can make them as strong or weak as you like by varying the dimensions. Here are some little ones:

http://tbn0.google.com/images?q=tbn:ugQr6eVjsGXF6M:http://www.taunton.com/finewoodworking/media/w00004_05.jpg

I didn't have to use pvc clamps because here in Maine we have a place called Mardens that's a sort of odd lot/salvage type retail place. Once a month or so I drop in to see if they have any clamps. Sometimes they have C-clamps or maybe bar clamps maybe even wooden screw clamps. Usually just a buck or two each. Sometimes less. After ten years of this I've got a pretty wacky collection of clamps. :D

As you can no doubt see from this pic:

http://im1.shutterfly.com/procserv/47b7cc24b3127cceb243c6c6d8cf00000036100AbNnLhizaOW KA

[Chip-skiff]

Ha! We've got some of the same clamps, but you've got more.

Sorry to say, it looks like a picture of what I'm trying to avoid.

I'll try the PVC clamp idea, but what size pipe would give you a reasonable bite on a 2" thickness? Seems like you'd have to use at least a 6-inch diameter, and have a strong grip to set it. It also seems that given the narrow bearing surface, you'd mark the wood unless you used some sort of pads.

Just checked the local ACE Hardware, and Pony 6-inch spring clamps are $4.50 each. Agony.

[tchiffriller]

I got some spring clamps from ace but there didnt seem to be any force behind them. But they were only a dollar so I guess that makes sense. But my dad got me some from harbor Freight that are really nice and they were 2 dollars a pop. They are the orange kind and I got them just for the same thing on my 11 foot canoe.

[Battenkiller]

I've got tons of Pony spring clamps (orange handle) and they are useful for lots of reasons:

-Clamping action is instantaneous
-Clamp exerts the same force as glue line shrinks
-They are cheap
-They are light and small
-Lots of them fit side by side on a workpiece
-I can store a zillion of them on a 3' long strip of plywood
-I can carry that strip of ply easier than a box

What I don't like about then:

-They exert the same force all the time
-They are not very powerful
-They can often be too powerful

I tried the black handled ones and they are weak, but that can be good. The HD green ones are as strong as the Ponies and get the call now at a buck apiece.

The 4" Ponies exert the most pressure/sq.in. on thinner stock due to a shorter working arm but are limited in depth for operations involving thicker stock. HD doesn't make a 4" green handled clamp or I would buy about 100 of them.

I would be leery about using heavy duty spring clamps on epoxy joints unless you are using spacers along the joint. They can exert a lot of force collectively and starve an epoxy joint.

[JimConlin]

At $2.21 each the 2" Pony spring clamps are a good deal.
http://www.tylertool.com/jor322sprinc.html

[Brian Palmer]

I used my 4 inch PVC pipe clamps on about a 2-inch thickness. You can always cut out a segment if it seems like too much pressure.

-- Brian

[Battenkiller]

As usual I messed up with tool names.

I use the Pony 3201 which is considered a 1" clamp and exerts a lot more force when you need it (like holding ribs down in a lapstrake canoe after bending them in).

The green handled Home Depot clamps are the same size as the Pony 3202 which is a 2" clamp. It is a bit stronger than the Pony equivalent, as tested by seeing how long I can keep one clamped onto my thumb.

The pain inflicted by the smaller Pony 3201 clamp is more than I can bear. ;)

[Bruce Hooke]

Sorry to say, it looks like a picture of what I'm trying to avoid.

Why? There is no harm in using a mixture of clamps as long as you pay attention to not overtightening the ones that can exert more pressure than you need and not spacing the weak ones too far apart. This is not hard to do -- watching the squeeze out gives you a good idea of what is going on -- and especially with epoxy there is plenty of leeway.

[SamSam]

PVC clamps work well. With time and a little money you could also make some clamps with a spacer and two legs bolted together with some threaded rod to make a U shape. That straddles the work and pressure is applied with two opposing wedges between one leg and the work.

Or two pieces of wood maybe 1" square by 4" long with a hole through the center for threaded rod to make an H shape. A spacer above the rod the same width of what's to be clamped allows the lower jaws to clamp the piece when the nuts are tightened.

Or maybe just threaded rod through some wood blocks would work.

Enter "homemade clamps" in google images for a bunch of ideas.

[PaulC]

Found these from a quick Google:

http://www.homebuiltairplanes.com/forums/showthread.php?t=1695

That is really clever!

[StevenBauer]

The beauty of the pvc clamps is they can be easily adjusted for the job at hand. For more clamping pressure you might use a 2" slice off the pipe. For less, maybe 1". For less still, instead of just slitting the circle of pipe you cut off make a second cut so maybe an inch of the ring is removed or 2" even. When you're done you can just throw 'em out. It was only a couple of bucks worth of pipe. :)


Steven

[StevenBauer]

These are clever, too. But a lot more work. Too much to chuck 'em after use.

http://www.homebuiltairplanes.com/forums/attachment.php?attachmentid=500&d=1123637497


Steven

[Chip-skiff]

After several projects where I used about eight different kinds of clamps and had to revisit the tension 3-4 times with uneven results, for the boat project I'd rather use multiples of the same clamp, whether steel spring or PVC.

My understanding (slight) of boatbuilding epoxies is that they don't require high clamping pressure, which can cause joints to be starved of glue. So spring clamps or PVC types would be good in that regard.

If I made 30+ PVC clamps, there's no way I'd toss them out. I've got scraps of hardwood that I've saved going on 30 years— there was a Wurlitzer piano factory in the town where I went to college that used to dump some amazing wood, including gorgeous thick birdseye maple and high-quality laminates. I just used a piece of that maple for a counter edge: waste not, etc.

Anyhow, thanks for your canny comments.

yrs, Chip

[switters]

Chip, agree with using the same type of clamp for chine logs etc. I didn't do that recently with epoxy and can see a difference, especially a bad idea with glue. Good to see someone else from the flyover states. Wyoming eh, why not a sail boat.:D

Tried the PVC clamps, they didn't work well on a radius.

[gert]

Nice boat Steve.
How about a "clamp off' :D

http://farm1.static.flickr.com/53/176767423_f6d2871716.jpghttp://farm1.static.flickr.com/64/176767401_c7563e1a9e.jpg

The reason theres no clamps at the middle is the rub rail "compensates" for some unfairness in the sheerplank top edge (there's a gap between the rail and the plank, that's later filled)

Home made clamps are the cheapest and can always be made to work; second choice is definatly the orange ones.

[Yeadon]

Interesting. Whenever I'm out and about, and see a clamp, used or new, cheap or on-sale, I buy it. Can't have enough.

Those ugly green spring clamps from Home Depot are great.

And now, to digress ... I'm also partial to the deep-throated vice grips that allow you to reach way in and put a bit of pressure where its needed.

Below, you can see the long arm of the vice grip.

http://farm3.static.flickr.com/2188/2325071704_2bf934b63a.jpg
http://farm1.static.flickr.com/129/382522182_29194a5655.jpg

[SamSam]

http://farm1.static.flickr.com/53/176767423_f6d2871716.jpghttp://farm1.static.flickr.com/64/176767401_c7563e1a9e.jpg


Home made clamps are the cheapest and can always be made to work; second choice is definatly the orange ones.

The wood ones are like a big wooden clothespin?

[gert]

Yup, made from MDF; they'r actualy "stiffer" (stronger) than the plywood ones.

[Chip-skiff]

Urrh don' spik Unglis. Pliss. What MDF? Many Devil Finger?

yrs, Chszpx

[bob easton]

Urrh don' spik Unglis. Pliss. What MDF? Many Devil Finger?

yrs, Chszpx

MDF is a laminated composite. More here: http://www.merbok.com/mdfoverview/whatis.htm

[almeyer]

Thought I might add my two cents worth. I made a bunch of these from scrap lumber, and they took a little more time than the PVC clamps, but they've already built two boats, so I can't complain. Adjustable, too.
Al
http://im1.shutterfly.com/procserv/47b7cf26b3127cceb0760761bd1b00000046100ActHLVi5bt2 Pg
http://im1.shutterfly.com/procserv/47b7cf26b3127cceb0760747bd3d00000046100ActHLVi5bt2 Pg

[Barrett Faneuf]

Add another vote for homemade ply clamps.

I made all of these for super cheap from 3/4" ply, they are very strong, and you can make the "U" as deep/wide as needed for your application. Using a wedge spreads out the force nicely for epoxied joints, keeping parts fair and preventing epoxy starvation. I think they used about a quarter of a sheet of $20 plywood that had already been used for a couple of other things, so about $5 and two hours' work for 60 or so clamps seems a decent deal to me.
http://farm2.static.flickr.com/1315/1431853778_adc556536a.jpg

These take even less time to make than the screwed-together version. For my application I placed them about every six inches.

My sheer and rubrails are bedded rather than epoxied, so they were inched into place with clamps, then screwed, and the clamps removed. The rails themselves forced a fair line. Granted, they're purpleheart....

Good luck!

[StevenBauer]

Barrett, have you seen the latest issue of Watercraft? You got a mention in the Silva Bay Shipyard School article. I visited a little with your Dad at the Boatbuilder's Show. :)

Steven

[Chip-skiff]

On a visit to friends, I hit every Home Depot between Cheyenne and Boulder, Colorado and couldn't find any $1.99 green spring clamps, except tiny wee lime-green buggers (I need a 2-inch plus clamp). They do have the standard 2-inch clamps with orange plastic tips, at $3.19, an opportunity I declined.

After fooling with the laminate clothespins and the wedgies and similar, I think the PVC idea is best for my application. The thick-wall (sch. 40?) white 4-inch pipe makes a decent spring clamp. I cut a 3-inch section and then a half-inch slot lengthwise. Takes a strong two-handed grip to set the thing, and there's enough pressure to mar wood surfaces.

So I cut a couple 3-inch lengths of fuel line and slit them lengthwise, to pad the jaws (and give it a finished look).

A 2.5 inch or even 2-inch section might do as well, with a bit less pressure. Seems like a setting tool would be easy to make, like a back-arsewards nutcracker.

Anyhow, thanks for all the canny suggestions—

Chip

[Paul Scheuer]

Trust me, some day you'll need more clamps- Usually when glue has been buttered on, and it's too late to go shopping

I'm a C-Clamp guy, and have built up enough of a collection that I don't know how many I have (or where they all are). When I have needed more pressure points, I have used short scraps of wood spanning two small blocks to get double the contact points. The accidental advantage is that the pressure can be measured by the deflection of the scrap pieces.

[PaulC]

From above for the nutcracker style:

http://www.homebuiltairplanes.com/forums/attachment.php?attachmentid=500&stc=1&thumb=1&d=1194614118

[Kermit]

I've made/used a bunch of plastic pipe section clamps. Little ones from 2" pipe, a mess from 4" pipe, and even scored some leftover "scraps" of 10" pipe from a municipal project contractor. The big ones are almost too strong. The little dowel "handles" are a worthwhile addition--otherwise you really need three hands or a wife to make 'em work out. I use short drywall-type screws into the ends of the dowels instead of nails. Just another way.

[Kermit]

Here's a link to a pic of PVC pipe clamping Devlin's DIPPER.

http://home.comcast.net/~jgj252/BB/ShearClampClamped.JPG

[Northernguy59]

where abouts in Wyoming are you located?

[Chip-skiff]

In the Medicine Bow range, SW of Laramie and just north of the Colorado line, on the Big Laramie River. Closest dot on the map is Woods Landing.

This landscape is better for whitewater boating than for sailing, what with the lack of open water and crazy winds. But I learned to sail in NZ (heaven on earth for yachties) and love it too much to let it go.

I keep hoping my partner will find a law prof job on some decent body of water. Being a writer, I'm relatively portable.

Chip

[JimConlin]

In the Medicine Bow range, SW of Laramie and just north of the Colorado line, on the Big Laramie River. Closest dot on the map is Woods Landing.

This landscape is better for whitewater boating than for sailing, what with the lack of open water and crazy winds. But I learned to sail in NZ (heaven on earth for yachties) and love it too much to let it go.

I keep hoping my partner will find a law prof job on some decent body of water. Being a writer, I'm relatively portable.

Chip
Huh?