Cutting running frame bevels, bandsoars, and traditional boatbuilding...

[Bob Cleek]

Hijack this, Mutha! LOL

I enjoyed Dave's description of cutting frame bevels on a shipsaw. It is indeed the way it was done and as he describes, it was a major league pain in the ass and took three or four guys and sometimes the loss of half as many fingers! LOL The problem is only compounded by the present unavailability of tilting head shipsaws, not that there were ever a million of them around anyhow.

Couple this with the question of "what's traditional anyway?" and I got to laughing. There's a gizmo on the market today for picking up lines. We all know the "traditional" methods... laying nails down on the line and stomping the pattern down on them, making little wooden pointers, and such. But, one of those guys who thinks he always has a better idea is marketing this thing that is essentially a big draftsman's articulated curve. You know those straightedges that have a lead rod inside a spring attached to the back so you can bend them and they'll stay put, or the cheapo version with the blue plastic around the lead? Well, this is a big batten with brackets attached to it and the brackets have knobs on them so with the knobs loose you can set it on the lofting and then tighten the knobs and the curve stays put so you can pick it up and lay it on your pattern and Bob's yer uncle. Of course, they are over priced and they crow it's the latest thing. Funny, though, I've got a 1916 textbook on boatbuilding and there's a picture in there of the same damn identical thing with an explanation of how to use it. There ain't much new under the sun.

That said, I'm still looking for the better mousetrap. Getting back to the cutting of running bevels and the lack of shipsaws...

No question in my mind that the sawn frame is the way to go when the scantlings demand it. Today, futtocks can be laminated sidewise with Aerodux or even epoxy. No need to cut the futtocks to exact size before laying them up, just rough it to shape like a do-it-yourself home-grown compass timber (which like shipsaws, are also in short supply these days... was it the chicken or the egg?). The better glues today permit use of relatively small stuff and if you triple them, you avoid the problem of the weak spot at the scarfs inherent in double sawn frames. If you scarf the futtock butts, they're stronger still. I've been playing with the idea of laying up sawn frames this way, but, while the lay up takes care of the sided dimensions, there's still the rolling bevels to be cut. Ah... there's the rub!

Now, as for table saws and tweaking stationary power equipment, well... I never was much for that. Needs to be done, but a pain in the butt! So, mostly, I rely on sneaking up to the line and then finishing off with sharp hand tools, which is infinitely more accurate and much faster for one off work. Getting a fair rolling bevel still takes a fur piece a planing with a ship's plane (which fortunately are still available) and if you lay up the futtocks with decent modern glue, particularly epoxy thickened with colloidal silica, it pays hell with your iron's edge, so cutting bevels close to the line is the object here. So, I keep mulling over whether there isn't some alternative to the make-do method of bolting a handle onto the tilting bandsaw table with a pointer on the frame and eyeballing it. The tilting table really doesn't do it because when it tilts, the work tends to want to head south... and in larger sizes (and I'm not talking about ship size stuff either) it becomes damn near impossible to juggle the feed, angle and outfeed all at once. Sort of like patting your head and rubbing your stomach at the same time. (What Dave didn't tell ya was that the sawyer who called out the bevels had to coordinate that just so with the kid turning the tilt screw SMOOTHLY AT JUST THE RIGHT RATE or the whole edge of the frame was gonna look like a roller coaster track! You didn't want to jump from 4 degrees to seven in the last three inches when there was three feet between the bevel marks! LOL)

So... now today there are "modern" powered tools that weren't around when shipsaws were handy and iron men and idiot boys like Flemming (man and boy) could be hired for pennies an hour, unions be damned. Here's the question for discussion:

Has anybody come up with a way to cut running bevels more or less "accurately" other than by eyeballing them on the bandsaw?

I have been playing in my mind's boatshop with the idea that maybe one of those new fangled hand bandsaws like Milwaukee and Porter Cable make might be adapted to cutting running bevels. I have no experience with the things, having just seen them in the stores. Still, I wonder if a jig, along the lines of the gizmo they have for taking up lines that I described above might be devised so that it could be laid on the stock to provide an angled surface along which a hand bandsaw or a good jig saw could ride and so cut an even running bevel. It would be beautiful if you could just set the heights of the bevels above the sided dimension of the stock and lay a batten along a bunch of little adjustable blocks and yield a nice smooth curve at 90 degrees to the molded side and then just run your jig saw or hand bandsaw along it. Or, is it possible to take that new shoe they make for jig saws that was written up in WB a couple of issues ago that allows the jig saw to cut rolling bevels freehand and put some sort of a guage on it to cut rolling bevels that way. (I bought one... pricey at $25 for a hunk of stamped metal, but much better than the stock flat fixed shoe on my Bosch!)

This ought to be food for thought. Let the problem be one that the "modernists" can weigh in on with all their "progressive" ideas and that the "luddites" like Dave and I can ponder! No fair pontificating that a computer controlled laser is just the ticket. I KNOW that, but if we could afford one of those damn things, we'd be having Gannon and Benjamin building our boats for us at half the cost of our tools!

[mmd]

Arrrrgh, matey! A foine propah question methinks, an' right on the money fer these hereabout places! Arrgh! Shippy 'n' all. (said with proper pirate attitude and gesticulations, I might add) :D

Really, a good topic for discussion. I have only been exposed to the 'round the bandsaw polka' for cutting running bevels, but I wonder if there are better - or at least different - methods for doing the same. I'll be talking to a few of the local pro boatbuilders in the next few days and see what pops up in the discussions.

[John E Hardiman]

As posted By Bob Cleek

Has anybody come up with a way to cut running bevels more or less "accurately" other than by eyeballing them on the bandsaw?
Sure, had one down a Mare Island, .....an 8', six-axis CNC vertical turret mill.... all you'd need is about ~$250K in some techie hardware, 4-5 draftsmen/CNC techs to code it up, a year or so to debug, setup, and cut, and a nice sharp ball mill. :D

A couple of years ago I scored a Craftsman model 113.248322 12" 2-speed tilting head bandsaw on closeout. I think they stoped making them, but it's just like a little shipsaw, right down to the handwheel to control the tilt of the blade. Not the finest tool I've ever owned, but it got out the bevels and oars I've made with it. Cut it fat and finish with hand tools.

BTW, I was lead to understand that you still dubbed out the bevels at regular intervals before going to the shipsaw on a big timber.

[Dave Fleming]

Since this is a VERY off the wall idea lets all take it with that in mind, shall we?

How about a CNC controlled tilting arbor shaper? A computer type person generates from a CAD layout of the hull the changing bevels. The rough frames, futtocks butted in the old days Cleekster, now SCARFED and laminated are fed through the machine for nice rolling bevels.

Hell if they now make and use 5 and 6 axis overhead milling machines to make blanks for entire hulls I don't suppose something as well....easy as rolling bevels on a frame would be too hard. I am visualizing one of the adverts in Professional Boatbuilder MMD, you seen one of those machines in action?

Probably hasen't been done yet because sawn frame wooden vessels are not in big demand.
I can see it now a huge TURCITE covered SS table top surrounding a 8 inch above table shaper arbor and with automated feed mechanism that matches the cutter rate of the shaper. Huge vacuum lines to remove the chips as the arbor almost imperseptively, moves forward or back 3 degrees to 5 degrees to 7 degrees and a frame all 18 or so linear feet of it is finished in about 3 minutes and its mate is now ready to be cut. Based on that scenario an entire set of frames could be done in one 8 hour shift.

[ 01-16-2003, 01:40 AM: Message edited by: Dave Fleming ]

[Dave Fleming]

JEH, if memory serves, a big if there!

Frames were dubbed after being erected on keel ribbanded in and fairing batten applied. Always going to be some bit off and then it was chalked and the dubbers would bring it into fair.
On big stuff futtocks were cut individually. Using one of these if it were a big well run yard.

http://pic4.picturetrail.com/VOL780/3097474/6294014/80852773.jpg

[ 03-04-2005, 03:57 PM: Message edited by: Dave Fleming ]

[RGM]

Tilting head shapers (been around for a long time). Tilting base plate jigs that fasten to stock router bases (pain in the ass and generally too much hassle). The shaper approach requires running the bearing or roller of the cutter against a batten or pattern which is fastened to your material. Using a router, the tilting base plate of the router is ran against a batten which is off set from your cut line the proper distance. As you can imagine some forethought and careful lay-out is necessary either way because when you start rolling the bevel the cutter will tend to move away or into your desired cut line. Nothing a little practice with scrap material won't cure. Most rolling bevels are cut a little proud and are finally taken to the line with hand tools anyway. For light work I get favorable results from my old Milwaukee "SawZitt" jigsaw. Dave F. will fondly remember that tool. The base plate was flat and at least 1/8" thick steel. The head of the jigsaw rotates for angled cuts. If you leave the locking screw slightly loose you can rotate the head to cut rolling bevels while cutting close to your line (eyeballing). Using the tool this way requires you to make some accurate index marks in degrees at a handy spot on the tool.

[John E Hardiman]

Dave;

I think there is a builder up here (Port Townsend?) that has something like a 10'x10'x40 or 50 six-axis CNC overhead arm mill that they use for cutting molds. However, they only cut lightweight foam, and I think that the feed pressure may cause errors to grow. I know that this is a problem when machineing propellers on 8-axis machines. In the automotive industry, where they use robotic arms to position and weld panels, they have to "train" the arm each time they change the setup to account for error and feedback tolerances. But still, it is an interesting idea... like that guy for N Carolina who took an X-Y plotter and hooked a router to it to cut out stitch and glue panels.

As for not dubbing before sawing, you may be right, as the frames would still have to be dubbed to fairness on the stocks. My memory comes from school, when they taught us "this is how we used to build 'um". For my own part I've always dubbed, or maybe a better word is "cut in", the calculated bevel with a little fat in a couple of places before sawing and then played connect the dots...I still sawed just wide of the line so maybe I've been wasting time.

[wolfietuk]

The big computer controlled machines are great if you want to make about 25,000 of the same pieces. for the one off boats (or about anything else) hand methods still are the most cost effective.

I will get my chance soon to use a ships saw on the spirit of South Carolina. The building frames are almost done. The shipwrights are doing most of the work now, the volenteers are to come in when they start the planking. Some planks will be up to 48'. Ill post some pics soon.

Rick

[jason stumpf]

dave,
i don't think the cnc tilting-arbor shapers are up to the challenge. here's why: the motors that drive the spindle up and down are designed to do only that; they don't have the power to drive a big, honkin' cutter-head through white oak. also, shapers are designed to be set up and locked down, then run. you introduce a whole 'nuther set of design complications if you ask a machine to remain accurate (and safe) if it is to machine and adjust simultaneously. that's a big reason why cnc routers are so expensive. also, its not practical (maybe not even possible) to use a stock-feeder to controll the feed rate of the work piece, so even if you could get the shaper to adjust the tilt angle, you still have the problem of the man and the boy cooridinating the feed rate and the rate of angle change. plus you would have to use a very tall cutter because the thicness of wood will be much greater as the angle becomes steeper. and shapers don't like to hog out large ammounts of material when you are hand-feeding, so you still would probably try to cut away the excess wood. as for multi-axis cnc routers, i think the programming might take a good opperator more time than it would require to rough out frames with an adze. after that the machine could whip them out. however, that is only one frame. the programming would have to be repeated for each one! sometimes hand work wins out! here's something to consider: if we're gluing up multiple layers for our frames (like three, say) would it be practical to loft them out so that the front layer's edge is the fore edge of the bevel, the middle layer's edge is the middle of the bevel, and the aft layer's edge is the rear part of the bevel? then you would have three lines to work toward with your saw or adze or whatever. its hard to describe here, but i'm thinking the inside edges would all be identical, so they could be glued up accurately. only the outside edges would differ, showing the shape of the frame and the angle of the bevel. of course maybe the lofting time would be too great....
jason

[Pekka Huhta]

Funny, Ive been toying with the same idea for several years now. Still dreaming of that 35' gaff cutter and trying to imagine every single way of building it prop'ly and still stay traditional. I have already toyed with my pet project, a 6' pram and practiced making the NC programs. 25 minutes per frame when you get the idea and then ten more to mirror it to the other side. Of course I can't build the pram with sawn frames but it's about the simplest possible model to practise with. (I have a few images of the pram and a few other models at http://www.puuvene.net/phuhta/pram/pram.html )

The only problem in getting the frames done with NC tools is to get your drawings in any 3d design program. That's what the new designers use anyway, but if you're planning to build an old design, it has to be lofted on computer. After thet the NC programs for the frames are done in a jiffy. The machines don't have to be "programmed" (as typing in millions of coordinates), a modern machine is simple to program. Remember that there is only one side, one surface to model. The inside of the frame can either be cut with a slightly scaled-down surface model of the outside or just whacked of with an adze.

For the machinery: it can be built (on a big project) or the frames can be machined commercially.

A regular bandsaw would be a bit difficult to automate, but doable. In any case it would help if the table stays straigth and the tool tilts. A router of some sort would be an alternative, it's lighter and easier to tilt (after you've built the mechanism, anyway :rolleyes: ). Among with the router or saw one would need a set of feeding rollers. When cutting the bevel the tilt of the tool would be a function of distance from end of the frame. Distance would be measured by the movement of one roller. Of course one could automate one of Dave's big jigsaws with roller-fed distance control as the man and a small servo motor as the boy on the handwheel.

For commercial machines water jet cutting is a promising method. Maximum cutting depths are 5-6", which would be enough for 3-4" frames. The only problem is slowness: on thickest frames the cutting speed would be even less than 50 mm/min (2"/min). An improvement would be abrasive water jet cutting, but the abrasive particles would be embedded to the wood - yummy for your tools. Otherwise the mechanism would be pretty similar to the first one, although the frame doesn't have to be moved but the cutting head moves around.

Commercial NC mills could be used just as well, just a basic 3-axis machine with a ball mill and there you go. The problem with 6-axis machines is to find one which is big enough, strong enough and has a hour rate less than $250 smile.gif The hour rates for 3-axis machines are cheap and machines are widely available. On the other hand the job is done quicker with the 6-axis machine.

Jason's idea about cutting the parts in steps is good and I have used it on several occasions. Not on frames though. A problem would be that you first have to scarph the individual layers together _before_ sawing and then get the distances between the layers OK. With the multiple lofting and keeping the layers in order during glue-up it is quite a hassle for a frame.

What comes to productivity is debatable. I have time to sit around in the office and toy with the models over several months or years on my spare time, but I just can't slip out and go to the boatyard in the middle ow a workday. Productivity is highest if someone else pays for it :cool: .

Pekka

[Cedarhill Boatworks]

Assuming that that you have determined the bevel on the frame, and assuming that the fram stock was not too big it may well be possible to use a porta-band to rough the bevel. I have never seen anything but metal cutting blades for a porta-band, and the throat width is pretty confined but on anything less than say 4x4 stock it might work, in fact I've been doing it in my head for a while now since I read Cleeks post, it probably will work. The difficulties are going to be having the frame securely clamped at a comfortable height, being able to see the outboard and fore/aft sides of the frame at all times, and the fatigue of trying to keep the saw moving as it tries to suck itself into the work, the "going south" problem of tilting a stationary bandsaw. The rip cutting is going to try to make the blade wander all over gods green earth. But...it certainly seems feasable, feasible? feasable.

[mmd]

Dave, I have not personnally seen one of the big 5-axis shapers doing boaty stuff, but I've worked for a company that used 5-axis mills for doing some pretty complex metal sculpting. I am currently working with a friend who is setting up one of the 3-axis routers that John H. mentioned to do stuff that it wasn't intended to do.

John H., I have not seen bevels dubbed in prior to shipsawing, though I agree that it is a nice, visible method of marking the piece. I've only seen it done with the required angle pencilled on the stock every foot or three beside the cut line, to be read by the guy who is controlling the tilt of the shipsaw. Regarding dubbing the frame first, I can hear in my mind old Teddy Snyder (RIP) of Snyder's Shipyard snorting in derision over "the time just a-wasted doin' cuttin' that you're gonna cut off anyways!" :D

BTW, this is the shipsaw at Snyder's. Note the railcar tracks to feed the timber to the saw. There is a second set of rails perpendicular to these that allows transport to the thickness planer inside the building in one direction and to the assembly shed a hundred feet away to the right. Also, note the narrow horizontal window, shuttered by two pieces of plywood, at the back of the shed that are opened when cutting to allow the free end of the piece to hang outside the building (over the river) as the heel is cut. I'm not sure what the little window with the shelf is for - I'll have to ask Phillip the next time I'm at the yard.

http://www.imagestation.com/picture/sraid36/p72e91464ed685b70ab0744efb49fa32c/fd26a69e.jpg

[Buddy Sharpton]

Rick, where are you building THe Sppirit of Carolina. Is it still out by the soccerfield out by the Maritime Center?

[scepticus]

Here's a thought that might work for relatively small stuff... stuff that you might be trying to cut on your 14" delta bandsaw.

Instead of simulating a tilting saw, tilt the wood. patch on a series of blocks or shims or whatever to build a false face on the side of the timber that is resting on the table. This false face would be built so that it is perpendicular to the desired bevel. Connecting the blocks with a batten would give a reasonably smooth transition from one to the next. This way the table stays flat and you don't have to worry as much about the stock sliding sideways.

[ishmael]

The problem I see with that scepticus is the making of the false face. At that point you might as well have planed the bevels in the frames. Except, perhaps, if you were building a bunch of them.

[scepticus]

Except that the false face doesn't have to be a complete face. It could just be a set of carefully placed spacer blocks of varying thicknesses connected with a batten or something similar. It doesn't have to span all the way across the face either. It just has to support the peice being cut.

I've never tried it of course, so it might be a disaster. I also don't have any plans to build anything that I think would necessitate this so I probably won't be trying it any time soon.

[Dave Fleming]

Couple of comments to the 'gang' all lumped in one reply.
Cleekster, I have this nagging memory of a boat building operation in the East Bay somewhere around Fremont or near where the old Peterbilt factory was. It was set up for mass production of power boats ala Chris Craft. I seem to recall they had a number of very fancy shapers (Swedish)all with SS tops and set up each to cut a particular part. Of course using patterns.
How off the wall is my memory?

RGM, I do realize that tilting arbor shapers have been around for quite a while. Dual arbor shapers are even older. ORTON in the San Franciso area made a number for Boeing for use on aircraft aluminum waaaaay back when. I thought that if the tilting arbor was servo controlled that the use of patterns would not be necessary. Have the coordinates in NC code and have some form of feed and material holder and the arbor would tilt and cut the bevels with the feed mechanism also hooked up to servos to advance the stock into the cutter head. I get these freebee metalworking trade mags with all sorts of machines for working metal and ,I in my usual foggy mindset, try to visualize how that mechanism could be translated into woodworking/boat building.

[Alan D. Hyde]

Those who've read "Building the Blackfish" probably remember the excellent introduction, which recalls the two hundred or so American shipwrights traveling overland to Lake Erie to build in short order a fleet which blew the British Navy off the Lake.

These men obviously didn't have a shipsaw. I assume they shaped their frames with hatchets or broadaxes or adzes.

On a one-off job by a guy (with only two hands, maybe four once-in-a-while) in his back yard, or on the foreshore, wouldn't their antique methods be just as practicable as the band saw approach?

Alan

[ 01-16-2003, 03:32 PM: Message edited by: Alan D. Hyde ]

[ishmael]

Alan,

I think you are very correct.

I worked with a ship's saw, briefly, when in school, and it and all the other nifty ideas for mechanizing the process are great...if you are in the business of production.

Working with hand tools (I especially remember an adze dubbing the frames of a schooner in the hands of one more skilled than I. Though they would have had the bevels brought close with a ship's saw) would be the way to go for the backyarder. In skilled hands, the hand blade can often beat the machine, on a limited scale--if you figure in the time to set the machine up.

But, for production work, some of the dazzling computer controlled millers...sound pretty interestin'. To be able to enter the offsets for any boat, tweak the machine a bit here and there, and start feeding frames...

Not very romantic, is it? :rolleyes:

Jack

[Bob Cleek]

Hi guys... Okay, okay, remember I said to begin with that computer controlled laser cutters were out of bounds. LOL Obviously, in a high production mode that could justify the tooling costs, I suppose you can do just about anything these days. The question really was intended to be limited to one off work like we might be looking at. (Nope, Dave, I don't recall that outfit in Fremont. Coulda been, dunno.)

I recall somebody in here once mentioning an outfit in Michigan or Minnesota, of all places, that turned out glue lam beams to spec for architectural applications. The had also won the contract to laminate prefabricated frames for the Navy's wooden minesweepers. I suppose they had the equipment to do some of the fancy computer controlled cutting some have discussed. Obviously, none of us have the money to call up and order our frames ready made because all our hard earned money already goes to taxes which paid for the Navy's frames! LOL

This rolling bevel connundrum has been floating around in my head for some time. I too build more boats in my head than I do in my shop. The more I think about it, the more I come back to the conclusion that the "traditional" method is probably the most efficient for a one off operation. Who hasn't daydreamed while doing repetitive tedious work that there must be an easier way? LOL

Mulling over the responses so far, it seems at least, perhaps, that the jig saw or portable bandsaw could be used with the frame laying flat over the edge of a work table to rough out the stock, cut to the line at the bevel marks, and then the rest dubbed or planed off. No two frames are ever going to be exactly alike anyhow and, human error being what it is, there's always a bit here or there that needs trimming to fit (or Gott Ferbit, building up if you cut off too much!). I suppose if you were doing a bunch of frames (my fantasy boat has 56 as I recall), you could make up a set of wedges for the range of bevels and use them as gauges for the more exact bevel mark cuts. Or, some sort of adjustable foot could be devised for the portable saw so the angle of cut could be set. (I NEVER trust the stamped metal indexes on any of my tools, though. Has anybody ever seen a 90 degree mark on a mitre gauge that they could rely on without checking the blade with a square?)

Now, the other prong of the question was about traditional boatbuilding. Could it be that the old timers have been here before and pretty much figured out the best way to go already? I'm not ready to swallow all the old lore hook, line and sinker just yet, but over the years I've been studying it all, their bait keeps winning the taste tests over and over again.

[ 01-16-2003, 04:02 PM: Message edited by: Bob Cleek ]

[ishmael]

Bob,

What fantasy boat are we talking here? What is the sided dimension of the frames we are imagining the best way to bevel?

I'd imagined, part way through this conversation, that a heavy portable jig saw, with the right blade, and that foot, could substitute for a ship's saw on frames up to...say for a 25 ft hull. In practiced hands of course. The operator would have to develope an accurate sense of bevel, and leave plenty for trimming.

Jack

P.S. Sorry, re-reading I see you've already thought of that. redface.gif

[ 01-16-2003, 04:30 PM: Message edited by: ishmael ]

[scepticus]

Actually, I think the way I'd try it is to make a square cut with my band saw on the fat side. After that, the bevel goes from a line on the other side to the opposite edge. Then either using a jigsaw with a rolling foot or perhaps my reciprocating saw if the timber was bigger than the jigsaw (or I couldn't find the rolling foot thing) just try to connect the line with the far corner. The only reason for cutting square with the bandsaw first is that it essentially makes the line on the opposite face visible.

Cut as close as you are comfortable to the line in both cases and clean it up by hand.

That's a larger scale version of what we were taught to do for cutting the bevel on the edge of a carvel plank. cut square with the band saw and then add the bevel with the block plane.

Somebody probably already said that. I really should have made sure that I read all the posts before saying anything.

[rickprose]

why wouldn't you just attack the frames with a sawzall and a demoliton blade, after drawing the bevel or saw-kerfing the friggin' thing or however you want to mark it, and get it close and then hit it with a good sharp plane? a sawzall, for frames that aren't sided too godawful big, is perfectly able to cut a rolling bevel (you ever used one? try getting the damned thing to cut anything but) and if the operator ain't too drunk or stupid, you can get it close to the line and finish by hand.
i also think those handheld electric hacksaws, what you're calling portable bandsaws, if you could get a wood-cutting blade, would do the trick.
and what about a chainsaw with a ripping chain? now there's chips-flyin', death-defyin' downright bare bones boatbuilding at its very finest, if you ask me...

[ishmael]

Rick,

smile.gif

From da man!

Jack

[Peter Malcolm Jardine]

Am I way off, or could you use an electric plane to rough out to the bevel then finish with a hand plane?
Just a question from someone who doesn't know... are you trying to speed up, automate, or make the process more accurate, or all three?

[ 01-16-2003, 06:45 PM: Message edited by: Peter Malcolm ]

[RGM]

Chainsaw can work great for cutting bevels. Done it before by laying out the cut line on both sides of the frame, tacked battens along the cut lines plus an 1/8". Fired up the saw equipped with the rip chain as Rick mentions. Gently let the chain saw bar "kiss" the battens as you merrily saw along. It was great fun as Rick also suggests. It helps if you have someone as a spotter on the farside of the piece that you are sawing so they can direct you with hand signals (thumbs up or down) if you're off the batten or riding it too hard and starting to cut into it. They clean-up pretty easy by hand afterwards. Rick, I like the "chips flyin, death defying" description. Screw the computers.

[JeffH]

Hiya Bob,

We've been using a tilting-head shaper with a top-bearing bit to do all our running bevels, from frames to planks, and it's about the best method for doing reasonably large material I've ever seen (see "schooner heron" posts for info on the project). Our shaper is modified with a servo motor on the tilting mechanism which is wired in to the shaper's power supply and operated by two foot pedals mounted on a small piece of plywood on the floor (the pedals have a long cord attached so they can be moved anywhere around the machine). There is also a sproket link to a large angle gauge mounted on the side of the unit. The beauty here is the the guy running the material through the shaper can control the tilt of the head, so no more shouting out bevels to someone who can't hear you anyway. The only problem we have is that as the angle of the shaper head changes, the height of the top bearing changes relative to the surface of the table. So, we need someone on the height adjuster knob (my job, usually) to keep the bearing on the batten as the peice goes through.

For planking, it works great. The chosen plank is first planed to thickness, the spiling batten is laid on top, and the plank is marked out. A long 1" X 2" batten is sheetrock screwed along the edge that will remain square. A worm-drive saw that has a short piece of the same batten screwed to the bottom of the guide is run down the plank, keeping the saw held along the batten. This makes a cut exacly 1/2" outside the line. A router with a flush-cut bottom bearing bit is run along the batten, cutting exactly to the line and exacly square. The batten is pulled up and re-fastened to the edge that will be beveled. The worm-drive saw trick is done again. The bevels are picked off the boat and, using a speed square, converted to degrees. These numbers are marked with a black marker on a small piece of duct tape stuck on the batten at the appropriate location. The plank is brought over to the shaper and table extensions set up as necessary. Initial angle is set on the shaper and the height adjusted as necessary. The power feeder is clamped down (it runs along the top of the batten), turned on, and away you go. The power feed runs at a constant rate, so it's just a matter of counting and knowing how fast the tilting servo operates so that the shaper head is at the right angle when the piece of duct tape goes by. With this method, one person, with only occasional help from another, can create a 30' long plank from rough board to hung on the boat, in about two hours. Much faster than I can clamp and fasten.

Approximately the same method was used with the frames. They are laminated, so both pairs of frames were glued up at once, cut in half, and run through the shaper using bevels picked off the lofting. Worked great.... There's only a little touch-up fairing of the frames to do before the plank is hung (I would NOT want to dub the frames that had been installed square with a batten and a hand plane. What a long, tedious, strenuous, and innacurate job THAT would be).

Interesting thing is, our boat is being built with hardly a hand tool in use. The caulk seam is cut with a power plane slightly modified for the purpose. The butt seam is done with a router. The plank is backed out with a power plane with slightly convex blades. Screws are pre-drilled and counter-sunk with electric drills and sent in with a power impact driver. Hand planes are only used to fair in the frames.

Cost? Dunno. I think the shaper, being a large, industrial one, was about $700 to $800. The power feed was another $250. The shaper head was $500, but it's carbide-tipped and bought because we were using angelique for part of the planking, and the sharpening costs of a normal head would have been around that anyway. The shaper was modified by a local electronics wiz (we've toyed with the idea of having the height adjustment under servo control with the tilting, eliminating the manual height-adjuster's job, but we're almost done so there's not much point of that now). However, we've been able to plank a 52' schooner, with three people (one of which was really working on planking for only about 2/3 of the time) in 2 1/2 months. Not too shabby.

Jeff

[ 01-16-2003, 11:11 PM: Message edited by: JeffH ]

[Dave Fleming]

Yeah RGM but, that goes against the "Gosh 'n Golly Whiz Bang Stuff" we have been hypothetically musing about.
<insert big grin here>

[Dave Fleming]

Good Post JeffH. Thanks for the information.

Do you see any future in a shaper for frames/planks reading NC code for most all movements?

[JeffH]

Dave-

Hmmm, dunno. My experience with CNC would say that writing the code for each and every plank would take longer than doing it by "hand". More accurate, perhaps, but this is a carvel-planked wooden boat we're talking about. If you were doing a whole bunch of boats at once, maybe, but who does that these days? Been a few years since I've seen a CNC machine, so maybe things have progressed some.........

Jeff

[ 01-16-2003, 07:25 PM: Message edited by: JeffH ]

[imported_Steven Bauer]

Wow! Lots of good stuff here.
Jeffh, that sounds awesome!

John E. I have that same 12" Craftsman. I got it used for $100. Not the best, but it is like a little ships saw. With a new blade it had no problem cutting the bevels on the 2" thick white oak stem of the Gardner skiff that I built.

Here's a coupla pics:

http://www.imagestation.com/picture/sraid47/p1eb9878e4fca39280a0b3df3981291f4/fcc4ff20.jpg

http://www.imagestation.com/picture/sraid47/pc9345737986b1b73b32fdb5873a4b2c9/fcc4ff17.jpg

I like Rick's method, too :D

[ 01-16-2003, 09:06 PM: Message edited by: Steven.Bauer ]

[holzbt]

For the size boats that most forumites are likely to build why not just saw out each futtock to the least bevel and then just dub them off with a power plane?