So what’s the best way to stitch up plywood for torturing?

[brian.cunningham]

All 4 panels are now cut out and ready to go.

I’ve sanded back the “black spots” to what I think is good wood.
I may put a little bleach on them before I reapply epoxy on it.

So what’s the best way to stitch up plywood for torturing?

It will have a curved transom, so the panels will butt up against each other at the stern, but will form a V at the bow.

Should I stitch them together and spread them apart. Or stitch the stern together and then work my way forward.

[Roseknight]

My first response is "with handcuffs" but that probably doesnt help much....
oh well maybe it will give you something to snicker about while you figure it out

[JimD]

handcuffs might do the job admirably, especially using those thin plastic ones you can buy anywhere. Brian, by four panels do you mean two bottom panels and two sides? Do the side panels have sheer logs glued on? Use spreaders at the sheer, if I understand your situation (far from given). does your boat have bulkheads? How about a parachute to survive the fall from the second story? I have built two kayaks, gonna convert one to a 'tri-ak' sailer this winter just for fun. jimd

[brian.cunningham]

LOL, actually I've seen the plastic ones used!

Two floats, two side panels each.
The sheerclamp is already glued on

Most tortured hulls like you say are just stitched up and spread apart at the shear, but having a relatively flat transom complicates matters somewhat.

[Jim Budde]

just finished hull of CLC 16' from plans. Bow is a little severe, so I started there, three or four stitches on one side, and then the other. Plans called for a spreader on the sheer about half way back. Had a little problem at first balanceing each side , but a little step back and looking, then tightening here and looseing there and hull turned out fine ... looks like it was poured from a mold

[John of Phoenix]

I used copper wire from Glen-L ($4.16 for 50 feet), but you can probably get something suitable from one of the orange box type stores. It's just 14 guage uninsulated copper wire. Steel is really tough to work with. Drill holes every 6-8" or as needed to stitch the panels loosely together. The distance back from the edge is the thickness of the plywood + 1/8". Get things assembled then gradually tighten the stitches to pull things into final position for the epoxy and tape.

Here's another little trick you may be able to use. "C" clamps and 1x2 "clamp pads" are used to spread the load across a greater area and prevent the stitches from pulling through the plywood as they are tightened. The rope pulls the clamps together. Apply your fillet and tape, let things cure, then disassemble. The best way to remove the wire is to clip the stitch on one side, heat the protruding wire with a propane torch, and pull it out with linesman's pliers. Removing stitches without heating it is a ROYAL pain. Fill the holes with thickened epoxy, sand it, paint it and you got a boat!! :D

Hope this helps.

http://glen-l.com/supplies/sup-stch.jpg

[George Roberts]

wet leather

[brian.cunningham]

George! What's up!

BTW here's what the hulls should eventually look like. Minus the sponsor paint tongue.gif

http://www.nigelirens.demon.co.uk/bayer.GIF

This has a small V, but the plan of action for me was to use one of curved deckbeams to hold the transom to shape and the two side panels butted up against each other.
http://www.nigelirens.demon.co.uk/blt.GIF

[JimD]

Originally posted by brian.cunningham:
George! What's up!

BTW here's what the hulls should eventually look like. Minus the sponsor paint tongue.gif

http://www.nigelirens.demon.co.uk/bayer.GIF

This has a small V, but the plan of action for me was to use one of curved deckbeams to hold the transom to shape and the two side panels butted up against each other.
http://www.nigelirens.demon.co.uk/blt.GIFYes, all that advertising is a bit garish. On my second 'yak i glassed the panels before stiching. Made a big diffence strengthwise when it came time to tighten up the wires. No worries about the wire tearing thru the thin plywood.

[Mark Van]

When I built my Glen-L 12 foot power skiff, I used plastic wire ties, they are much easier to pull tight, and after the epoxy cures, they can be cut with a sharp knife.
Mark

[George Roberts]

Brian --

I have been expanding my shop - 1600 sqft, 4 french doors, 3 HVAC systems, 2000bd ft of real nice lumber.

With the help of 2 'prenticess, and a couple occassional specialists we turn out several nice boats a month.

[brian.cunningham]

After cutting up 20ft of copper wire into 3” lengths. I stitched one of the floats together and tried the open it like a book method.

First shearclamps down, or upsidedown. This keep everything symetric and the shears level, but, since I don’t have access to wedge the hulls apart, I wasn’t getting enough separation at the bow. All I wound up with was a vee shape separation at the back.

Since I haven’t cut the access of the shearclamps off yet, I decided to hang both ends and try doing it upright. Since it would need to be flipped anyways to lay the tape in, this seems to be more logical.

I could now wedge them apart and get the fullness in the bow that I wanted. I need to correct the rack in it though, this is making the port side convex and the starboard side concave. I’ll make up stick to hang a weight in the middle and see if it hits the keel.

Looks like I’ll have to undo at least the stern 3rd of the wires. The sides are still at a vee and not butting up.

I may also pick something else beside the deckbeams to form the stern. After seeing it, not quite the radius I want. Though it forces more of the volume forward, which will be good to stop pitchpoling. The flatter transom would keep it from burying. Some kind of form is definitely needed, otherwise the ply would crack for sure.

Glad to hear your doing good George.

[Andrew]

I've had luck using 50lb (or stronger) monofilament to sew up panels. By lacing up the holes with the monfilament it's possible to pull the panels up easily single handed.

[brian.cunningham]

Pictures are here (http://temp.corvetteforum.net/c4/bcunningham//swiftwood/torture.htm).

Day two
I tried both the wire and the tape method. The tape method just wasn't going to work for me. But working with it showed me that the twist in the transom was to great. I could not make the two pieces but up against each other. A small vee would need to be left at the stern. So they will be more like the outriggers in the pics above.

I decided to use two of the deck beams to help form the stern. This would make it a triangular shaped transom, with curved sides. As you can see in the picture below the buttjoints as making the curves assymetric, and covex instead of concave.

The overall shape is getting where I wanted it. Now I'm starting to like the triangular stern better. The curve at the transom sides dropped off about 3ft in, the sides are straight vees. I'm desiding whether or not to put the bulkheads in before I tape. I could force more fullness, curvature into the side, but I'd also risk just having a bulgre in the hull where the bulkhead is.

I got the shear to start to behave by putting in spreaders where the buttjoints are located.

Next task it to get the rack out of it.

[Mac_Muz]

Check out your water damagaed topic. I would not use bleach... Mac

[brian.cunningham]

Mac, what would you use then?

I'm finding the missing pieces to the puzzle over on:
http://www.kayakforum.com/cgi-bin/Building/index.cgi/read/70286
and
http://www.clcboats.com/forum/bbs.pl?read=20045

Seems I missed at least one piece.
I'll need to:
1) install the bulkheads
2) establish a bevel at the keel, 1st filing the ply and then build up the edge with either glass or a piece of wood cut at the correct keel angle
3) make a jig to hold the shears where I need them to go.

The bulkheads will be easy enough to build.
The keel piece can be formed from a triangular piece of wood.
The jig will be the tricky part, it could be either internal or external, but would assure that the port & starboard amas match each other.