If this is your first stitch'n'glue, best keeping in mind those first stitches shouldn't be too tight as you fit the frames. Tightening stitches comes later.

Loosen stitches until you can fit those frames, then begin tightening them (some may need replacing) again as you add the remaining panels, a little at a time.

It's a process that's been worked out over many years building many successful hulls. All the parts need to be in place before you have stitches tightend 100% so there's going to be quite a bit of 'back'n'forth' working out the stitch tensioning vs. panel positioning.

   In addition to easing the stitches, you can also take a sanding block and round off the inside corners of the panel just a bit to prevent them binding.

That's a great addition Mummichog, I'd forgotten how important that is when panel edges have to be in contact with one another along a delicate corner.

Without 'breaking' the machined edge first the ply veneer can tend to splinter and the edges want to resist staying in proper position.

Sanding block puts a very small bevel on the corners that greatly eases panel-to-panel contact when stitched up tight enough.

Too, remember that stitch'n'glue doesn't require 100% contact at EVERY edge either! Small gaps are common, easily filled with epoxy later on. More important is to have everything fitted so the hull shape's as fair as a builder can get it before starting to tack-weld then add fillets.

 Ended up cutting all the stitches, taking everything apart, then sanding a bevel into the inside edges of both panels. Then when stitching back together, made sure to leave them extra loose (like 1/2" space between holes and first twist of wire). It still required more force to flatten out than I was expecting, but with the aid of two 25lb bags of lead shot, I was able to hold down flat enough to stitch the former bulheads in. Only problem now is the 1/4" or so gap between panels down the keel-line. I assume I'll be able to tighten the stitches later on in the process to close this up.

   Oh, forgot to add the bevel seems critical in keeping the rockered end portions from wanting to climb all over each other when folded out, prior to adding the bevel, one panel would pop up over the other.

You're on the right heading now, proceed!

Not unusual either to add some extra stitching holes (find a source for numbered drills, the smallest common hardware store item being 1/16" is too big) where and as necessary to bring things together more neatly. Also use of clamps, both bought and home-made, web tie-downs, even strapping tape, anything to bring things into position better than overstressing plywood with point loads of copper wire stitching.

Forgot to add:

If your local hardware store doesn't carry number drills, look in their welding department - or a welding supply house - for a nozzle-cleaning tool w/various bits included. They'll all be smaller than 1/16", one should be fine for the 18 ga. wire we use though I forget exactly what dia. that is.

   Didn't you stitch them flat?

RE: Sassafras 16- folding out the keel panels

 » Submitted by KX5002 - Tue, 10/18/22 » 7:14 AM

   Didn't you stitch them flat?

Per the instructions, I stitched all the way down the keel side of the #1 panels while they were laying on top of each other, then unfolded them and held them down in the middle with about 50lbs of weight. This allowed me to get the former bulkheads installed. I couldn't get the last stitch on either end closed all the way, and I also have about 1/2" gap between panels down the keel line, which I'm hoping I can close once all panels are installed (will probably need ratcheting straps or something to squeeze while I tighten the stitches).