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Re: Skin-on-Frame: Non Wooden Stringers
By:Paul G. Jacobson
Date: 1/29/2003, 10:31 pm

: One thing to remember about wood is that it takes a fair amount of equipment
: to work with it. Since the height of my technology is a circular saw this
: puts me in a bit of a bind. Yes, I know I could do it with the C saw, I
: have done that sort of thing before, but it is a pain in the a** to set it
: up and do it right.

You have to remember that you are considering building a boat design which pre-dates power tools, and in fact pre-dates the introduction of metal tools.

You could build these boats with stone tools. Problem is, Home Depot wouldn't have a clue about what kind of stone to sell you. :)

Most circular saws can accept an attachment called a ripping guide. For the 6 or 7 long pieces you would need to cut, this would work just fine. If you don't have one, you can clamp a block of wood to the bottom of your saw and use that for a guide. Use a sharp blade (disposable ones are as cheap as a buck or two each when on sale) and take your time.

You will probably want to get a sabre saw for cutting the forms, but you can do this by hand with an inexpensive ($6) coping saw. Since low-end sabre saws start as low as $20, you might go for that instead of the coping saw. Some designs allow for frames which are either cut from plywood, or built up from relatively straight wood pieces, which are screwed and glued together.

If you go with the designs which use steam-bent ribs you can split the rib stock from a block of wood with a froe (or even an old power lawnmower blade) and a mallet or wood block.

: I am looking for the simplist construction method possible. To that end, I
: will almost certainly use plywood ribs. The choice of stringers is still
: up in the air. At this time I am leaning toward a mix of galvanized
: conduit and wood gunnels. I am going to use wood gunnels so I can use the
: staple method of attaching the canvas.

It is just as simple, and some would think it was simpler, to NOT staple the fabric to the gunwales, but instead to sew the skin together. It may be cheaper, too. When you use staples you have to fit another wood strip over them (a rub strip) to prevent the fabric edges from ever getting snagged. That is one more wood strip to buy or to rip. With interior gunwale strips (also called sheer chine strips in some books) and the covering rubstrips you would need to cut or buy 4 wood strips. If you are trying to get around making these, then you don't want to go with staples. If you CAN make this many strips, you might as well make a few more and use those for the keel and chines.

: I think the galvanized conduit is at least good as the PVC and easier to work
: with than wood. . .

NOT TRUE! Wood and PVC can be bonded with suitable glues. PVC can be heat welded or solvent welded. Because of the galvanized coating it is not safe to weld conduit. You can solder or braze it. Soldering is is not going to be as strong a bond as brazing, so for all practical purposes you will want to braze or bolt any joints with conduit.

If you go with mechanical fasteners (bolts and nuts) you'll spend more time drilling holes in the harder galvanized steel than it would take to drill similar holes in wood or PVC. Fastening the round conduit with bolts causes the pipe to crimp and collapse as the bolt is tightened. Some people building other items (not kayaks) with conduit will flatten the ends of the pieces before drilling holes in them. Others will plug the ends of the tubes with short sections of hardwood dowels. 1/2 inch (nominal) electrical metallic tubing (emt) or common conduit, takes a 5/8th inch dowel to plug it. If you use a 7 to 8 inch long dowel and secure about 4 inches of it in the end of one piee of conduit you'll have a stub which can be inserted into another piece of conduit. In this way you can join two sections end-to-end.

: . . .It will take a pretty good whack to put a permanet bend in
: it.

And there you have it. The boats HAVE bends in them. And to get conduit to bend, as you say, takes "a pretty good whack". the objetive is to get the long strips on the boat to bend evenly, and conduit will fight you. After you have the conduit bent you then have the problem of fastening these parts to the frames. And finally, you have to fasten a wood strip to the length of conduit along the gunwale if you plan to use staples.

To my mind the hassles involved with working with conduit seem to far outweigh any advantage in using them -- unless you are either desperate or work for a steel company and you are doing this to show that it can be done.

: . . .And by that time I should know if this paddle thing is for me or if I
: should just stick to my motorcycle.

Actually, motorcycling and canoeing or kayaking go together very nicely. Sometime I'm going to design a nice ramp for getting my motorcycle into my canoe so I can ferry the bike across rivers and pothole lakes.

:All that said, I still have some time
: to wander around the local adult toy store (Lowe's) and look at other
: alternate materials. (I noticed some slats in there the other day. You
: wood folks mights win out yet) (i wonder if you could do a strip and glue
: with slats)

If you don't mind spending the money, you can buy beautiful, milled, wood in long lengths at the back of most of these homne centers. While these milled materials are usually used for trim in homebuilding, they would certainly serve for boat building. Some might need additional work, and others are ready as they are. It depends on the profile you select. There are even molded plastic trims which have the coloration of wood. over their full length they are flimsy, but they'll do if you just use them to tie together closely-spaced ribs.

Hope this helps.

PGJ

Messages In This Thread

Skin-on-Frame: Non Wooden Stringers
John -- 1/27/2003, 1:40 pm
Re: Skin-on-Frame: Non Wooden Stringers
Shawn Baker -- 1/28/2003, 1:09 pm
Re: Skin-on-Frame: Non Wooden Stringers
Pete Notman -- 1/29/2003, 3:41 am
Re: 'The Aleutian Kayak'
Shawn Baker -- 1/29/2003, 4:33 pm
Re: Skin-on-Frame: Non Wooden Stringers *LINK*
Peter Robinson in Oz -- 1/29/2003, 3:21 pm
Brinck Baidarka *LINK* *Pic*
Travis Kinchen -- 1/29/2003, 11:46 am
Re: Skin-on-Frame: Non Wooden Stringers
Tom Yost -- 1/27/2003, 6:04 pm
Re: Skin-on-Frame: Non Wooden Stringers
Travis Kinchen -- 1/27/2003, 3:21 pm
Re: Skin-on-Frame: Non Wooden Stringers
John -- 1/27/2003, 3:54 pm
Re: Skin-on-Frame: Non Wooden Stringers
Jim Kozel -- 1/29/2003, 6:28 pm
Re: Skin-on-Frame: Non Wooden Stringers
Travis Kinchen -- 1/28/2003, 10:50 am
Re: Skin-on-Frame: Non Wooden Stringers
Tom Yost -- 1/28/2003, 12:15 pm
Re: Skin-on-Frame: Non Wooden Stringers
John -- 1/29/2003, 8:09 am
Re: Skin-on-Frame: Non Wooden Stringers
Paul G. Jacobson -- 1/29/2003, 10:31 pm
Re: Skin-on-Frame: Non Wooden Stringers
Eric -- 1/29/2003, 10:44 am
Re: Skin-on-Frame: Non Wooden Stringers
srchr/gerald -- 1/27/2003, 7:32 pm
Re: Skin-on-Frame: Non Wooden Stringers
Paul G. Jacobson -- 1/27/2003, 11:52 pm
Re: Skin-on-Frame: Non Wooden Stringers
srchr/gerald -- 1/28/2003, 11:22 am
Re: Stick To Brooms ! ;-)
Eric -- 1/27/2003, 5:57 pm
Re: Skin-on-Frame: Non Wooden Stringers
Nick Schade - Guillemot Kayaks -- 1/27/2003, 2:14 pm