Lewis Boat Works: Custom Boat building and Plans
Kris's LilJon8
5.22.2002
Free Plans, design pictures and updated info:
(Here is some of the email exchange, along with pictures. We had an email lost between us so there may be some info added that predates these pictures).
yes, I've decided to build a variation of the Lil'jon 8, and I've started to gather the materials. With any luck the project will be complete in 3 weeks. One question...where do you purchase the fiberglass tape and epoxy? I was told to check out the automotive stores, is this right? At any rate, the boat will be built and once photos have been developed I will be sure to send them to you.
Wish me luck...
Kris
Well, everything is going great. In the past two weeks I've been too busy
to build (college exams,) but I have gathered all materials necessary and
the building starts next weekend. Thanks for the concern, and you will not
be disappointed in the photos. I should have no problem sending them, but
if I do, you will receive hard copies. Wish me luck.
Kris
Every thing went well till the bottom. When attaching the bottom, the 3/8 plywood would not flex. So I soaked the last 3 feet with towels and then worked it from the front transom. This worked till the front transom let go from the furring strips and led to a 4 hour delay. If Iwere to build another I would use 2 sheets of 1/4" plywood for the bottom (laminate the two together) and use 2x2 for the chine logs. If using 2 sheets for the bottom the attachment would be much easier. But all in all the project went well. This weekend I'm working on the seats and the finish. Any tips for using epoxy?
kris
During subsequent e-mails, it was established that Kris added additional some additional framing to the front transom, re-wet the ply and put the ply back on. This time it held. I suggested some alternate methods that could have been used, such as cutting Kerfs in the ply or putting a 'Set' in the ply by leaning it against a wall and bending it for a while. Perhaps 3/8" is a little too thick for this bottom. Then again, Kris's suggestion of laminating 2 sheets of 1/4" has merit. Maybe a 2' wide section of 1/4" down the middle of the boat would be sufficient. The only problem with doing your own laminating is avoiding the voids. For laminating, precoat the wood, then spread thickened epoxy on both layers and use a lot of mechanical fasteners to ensure a solid seal. Squeeze-out should occure around all the edges, provided the clamping (screws) are done from the center out. Using a Glue Spreader should help reduce the amount of epoxy used. This is a trowel like device that puts lines in the glue. When the pieces are laminated , the raised portions of the glue flatten out to fill and make a level and even layer of epoxy throughout the lamination. If using Kerfs, the cuts need to be 1/3-1/2 the thickness of the panel, and perpendicular to the direction of the bend. This means that if the length is being bent the Kerfs need to be cut across the width, about 1/2" to 1" apart, thereby creating spots that are thinner and easier to bend. Once the wood is fastened in place the Kerfs are filled with thickened resin, making it a solid piece once again. The same method may be use on any kind of wood, allowing bends to be done that are otherwise impossible with any other method. The best way to describe this method is to picture a 4x8 sheet of ply, with lines drawn across the width, at 1" intervals, then take a circular saw, set to half the thickness of the ply, and cut along the lines. This should make the ply bend as easily as a sheet half as thick as the original. Once bent and in place, slather some epoxy putty in the remaining gaps and Voila, solid ply again. The Kerfs should be on the inside of any bend, allowing the outside veneer to take the stretch load, instead of the inside veneer(s). I also suggested that the chine logs be made of a harder wood, like oak. Kris said that that might work, and that he would also consider carving the chine out of a 2x8 to make a 2x2 chine on the curve. This would allow the use of longer screws with more bite. I'm thinking that oak chines along with Kerfs would be the way to go with 3/8" ply. With 1/4", it bends well enough, and a second section could be laminated. The only concern that I would have is the increased weight, but that bottom sure would be bulletproof.
