First course of planks stitched with the help of my loops... |
Ah, but I'm getting ahead of myself... Before the stitching comes the rabbet joint procedure. Let me tell you that in all the years I've been doing woodworking, I've never done anything like put a 1/8" rabbet in a 1/4" sheet of plywood, especially on a curved surface. Luckily, I had a router and the 3/8" rabbet bit, so no extra expenses there. I clamped sections of the planks together on my workbench and routed the stretches between the clamps. Move clamps and continue on. I made sure to mark my templates to ensure I rabbet the correct edges because the first two planks are concave and it's a bit non-intuitive.
Before I got to the actual stitching part though, I had to drill the holes. I wanted to ensure that they matched up along the curve. The directions say every 4", so I made a gauge stick. One inch wide, so that each half would be the appropriate 1/2" inset for drilling the holes, with two 1/16" holes exactly 4" apart. One hole I fed a short piece of wire through. The wire goes into the previously drilled hole in the boat part, positively locating the hole to be drilled. I then just worked my way along the edge of the first plank. I then held the plank in place (with the help of my string loops) and made a mark on the bottom that corresponded exactly to the first hole on plank #1 with the bow edge perfectly aligned. I then stitched the first hole. This helped me keep the alignment so I could make the corresponding marks along the bottom using the previously drilled holes in the plank as a guide. BTW, the holes are located about 1/8" from the end of the rabbet (3/8" rabbet + 1/8" gap = hole 1/2" from edge), so it looks a bit fragile. I had no problems however, as long as you keep the planks wrangled. Once you get about half way down, the rest of the plank is sufficiently supported. Oh, BTW, I also used a back block when drilling all of the holes to eliminate tear out on the back side. I might have forgotten to do that as a pretty standard woodworking technique, regardless of it being a 1/16" hole had I not read it in one of the blogs.
Difficult to see but the wire poking out the back left goes into the previously drilled hole. |
OK, so now back to the stitching... It was a bit scary and tricky. I found that if I bent the wire into a lopsided staple, then I could put the long side into the plank that's at a bit of an angle, slide it in a bit to get it started, then put the short side into the bottom and slide them both through. Then I smash the bend in the staple flat across the seam with my finger to take out some of the slack (making sure not to crush the rabbeted edge that's sitting on the sawhorse), then duck under the boat. I make sure the legs are bent sort of parallel with the boat bottom, then twist so that both legs are wrapping around each other equally, kind of like a DNA double helix. You don't want one just corkscrewing around the other. Twist placement is also important. I wanted the crotch of the twist to be right on the edge of the rabbet so that the crotch sits naturally on the corner of the plywood. This also draws the joint together very efficiently.
I was also concerned that the stainless steel wire that I can get for cheap at work would be too stiff and/or sharp for the 1/16" holes and the 1/4" plywood, with the 1/8" rabbet. So far, so good. I left the stitches a little loose on purpose and I figure I can always tighten them up as needed.
Second course stitched, ready for the transoms! |
According to the manual, after the second course is stitched, it's time to attach the transoms. I'm experiencing a slight delay here however because my supposedly 9mm transoms are actually two 6mm plies cut out at the same time with the template. That means I have to laminate them together perfectly. I've got one screw through all of the layers where the handle cutouts are. That should help. After the glue-up, then I've got to cut out the handles and route the edges. I figure this will be a lot easier while I can clamp it to the bench than when it's part of the boat.
Starting to form a boat shape! |
So here's where I have to make a confession... After getting planks #1 and #2 stitched on, I held the transoms and bulkheads in place and they didn't line up. I thought I had installed the planks backwards, bow to stern! After checking the plans, and some monkeying with the curvature of the hull, I managed to get the boat within striking distance of the stern bulkhead. WHEW! At that point, I clearly labeled my templates and will put masking tape on the oak for future reference.
Not bad looking for $27 oak plywood... |
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