Copying the hull panel shapes from a stitch and glue is a lot easier than trying to take lines off of a rounded hull. You already know the bpat was built from flat panels, and those panels have either sharply defined edges at their seams, or scarf joints made so that the seams have no edges.

> You could build a strongack and curve panels around it, which would allow
> trimming panels as you go.

I assume what you mean is to mount the boat firmly to a strongback and then lay a wood panel against the side of the boat. With the help of several friends the panel would be pressed against the boat and someone on the `boat` side of this setup would would trace around the boat with a pencil, drawing the outline on the panel. This sounds to me like you would need 4 hefty friends to maneuver the panel while you did the easy pencil work.

> The problem, you see, is that much of a stitch and glue (S&G) boat is
> derived from the shape of the panels, which are layed out as flat
> patterns. Figuring out what shape, when flat, will result in the right
> shape when bent and joined and bent some more, is not all that
> straightforward.

I disagree here. The flat pattern is the answer, not the problem, and you have already provided a rather straighforward solution, below, so you are contradicting yourself. You can pat yourself on the back now, and again later.

> If you could figure out what boat it is, or where the plans originated
> you'd be best off both ethically and economically.

Well, ethically at least.

> You could probably use butcher paper, tacked to the hull with rubber
> cement (on the paper ONLY), and trace the panel shapes. Only do one side
> of the boat. Then trace those onto plywood stacked two sheets (face to
> face) thick. Now you cut out BOTH SIDES of the boat together. Absolute
> symmetry from side to side is essential to build a straight S&G boat.

Butcher paper is good for a lot of things. I wonder why butchers use so much plastic wrap these days.

If you don't have a nearby art supply store that sells butcher paper rolls, or if you choke over the price of a roll of the stuff, there are alternatives:

Rolls of fax paper are usually 100 feet ( 30 m) or more and will serve nicely. Readily available at office supply stores. Or, get a few pages from the daily newspaper and tape them together to form a long piece.

You will want carbon paper. Check at the office supply store for a package of 10 sheets. Sewing supply stores also sell dressmakers tracing paper which is similar.

You will need a light tack adhesive of some kind. Rubber cement is good. There are several spray adhesives that are also good. Right now my favorite is a product sold by Avery and Dennison (and maybe several other brands) which is in the form of a dry glue stick -- those lipstick shaped glue sticks that kids use. This particular glue stick has an adhesive just like the sticky strip area on 3M post-it notes. Rub it on your paper, give it a second or two and it becomes a repositionable piece of paper. Think of it as a 20 foot long post-it note. Double stick tape is perfectly fine, too.

Whatever adhesive you use: use it sparingly, and put it on the paper, not on the boat. Two reasons for this. The first is that the boat stays neater. the second is that the adhesive can then be used to hold the pattern to your wood panels when you go to cut them.

Ignoring the deck for a moment, lets assume your boat's hull is made of 6 pieces, 3 on the left and 3 on the right. We only need to trace one side. As Mark points out, you can make two copies. Flip the boat bottom side up, and by eye get a general idea of how your paper is going to fit on the first shape you widh to copy. Put a stripe of adhesive, or many dabs and splotches of rubber cement, longwise down the approximate center of the paper. If you use rubber cement, wait a minute or two for it to dry. Lay you paper FLAT down the panel you want to copy. No wrinkles, creases or folds permitted. The paper must completely cover the part. If you did not line it up properly, remove it and try again. If the paper is too narrow ( a possibility if using 8.5 inch fax paper) you might want to tape another sheet on to make it wider where necessary.

Starting at one end, gently lift the paper so that you can slide your carbon paper between the boat and the paper. The carbon side faces up, so you can see it. gently replace the paper. Use a stick, dowel rod or stiff pencil, and gently rub the edge of the boat. You don`t want to crease the paper, just press hard enough so that the carbon paper makes an impression on the underside of your pattern paper. Gently lift the edge of the pattern paper, without disturbing the adhesive, and slide your carbon paper down and trace another few inches. Keep up the tracing and shifting of the carbon paper until you`ve done one edge. Do the other edge. Before removing the pattern paper, gently roll back the edges and examine it to see if you have a nicely defined edge. If you have missed a spot, go back with the carbon paper.

You MUST remember that the image you have traced is now a mirror image of the part you want. There are several ways to handle that. One is to ignore it. You are going to need two parts that are mirror images of each other, so there is no problem. Stack your two panels face to face to avoid splintering the good side of the wood, flip the pattern so you can see the lines, using the same adhesive you used before, adhere the pattern to the wood and cut right through it and the wood.

There is another method, which you should try first on a small scrap: You will still stack your panels face to face, but this time keep the carbon image down when you place your pattern on the stack of wood. Use a clothes iron at medium heat and iron over the pattern, going over the area where the carbon paper has left its lines. Using the heat from the iron you should be able to transfer some of the carbon image directly onto the boards. Once the image is on the wood it obviously can not shift around as you cut. Also, if your tracing has irregular edges, once you have transferred it to the wood you can take a long, thin strip of wood and use it as a batten to `fair' those curves, turning the irregular edge into a nice smooth one. While you are at it, you can measure those curves, either with a tape measure or by making alignment marks on that batten. You want to make sure that the curve from part A that has to match with a curve on part B is exactly the same length. Since you are tracing from the same edge (twice) you should get the same length both times, but it never hurts to double check.

The lines you have traced will be slightly larger than the actual size of the original parts. This is partly because of the layers of fiberglass tape and resin which were used to build up the edge seams. You can either compensate for this by cutting a 1/16th inside the lines, or just build a boat that is going to be 1/8 inch to 1/4 inch wider and deeper than the original. Not a big deal usually, but something you should know about.

Since you have a completed boat it would be a good idea to use a tape measure and measure the hull at various points, say the widest point, the deepest, the width 5 feet from the bow or stern, etc. Use this data when you stitch together your new panels so your boat has the same shape. You may need to cut a few pieces of wood as temporary braces to force the sides apart to the correct width if you stitch too tightly. Knowing what the measurements out to be can certainly help.

> Do everything you possibly can (e.g. cutting out panels, drilling holes
> for stitching wire) to both panels at once, with them face to face (or
> back to back)

I'm not sure this is a good idea. I'd worry more about having the holes from part A match the corresponding holes on part B than having part A for the left side match part A for the right side, and neither one match any of the part Bs.

> Good luck.

I concur :)

> P.S., How'd I do guys? Maybe I should actually TRY this stuff, eh?

Definitely Mark, but we'll give you a pass for a few more months at least.

Hope this helps Paul Jacobson