Builders' Forum Archives
Re: West River 18
Posted by Dave Houser on Jan 10, 2005
A small gap between panels in no big deal. Mask the outside with tape to form a dam and fill the gap with the thickened epoxy when you make the fillets on the inside. I filed a 1/4 inch wide gap this way with no problems. I like to thicken with colloidal silica (Cabosil) and color with just a little wood sanding dust to match the okoume. With a good color match no one notices the wider fill.
I like to tab to remove the wires. The trick to tabs is to mask the outside seam between the holes before you tab on the inside. Don’t thicken the epoxy too much, thinner than mayo, so it settles into the seam. Make a very small radiused fillet to tab between the wires. I use a Popsicle stick to strike off the tabs. It is also possible to just squirt in a small bead of thickened epoxy with a glue syringe. However you do it the tab needs to be smaller than the finished fillet. After the tabbing cures pull the wires. If you got any epoxy on a wire heat the wire and pull it out with pliers while it is hot. Then mask the holes and balance of the seam. Make a thicker wider fillet, using a larger radiused card or stick to strike off the final larger fillet. The small tabs should be completely buried in the larger fillet and they will not snag the larger radiused strike off tool. By masking (and if you don't make the thickened epoxy too thick) the epoxy will fill the holes and cracks without dripping or wetting the outside wood, no filling effort and no sanding off drips will be required. Do not worry about filler getting through the tight spaces. The epoxy finds its way through as long as it is not a dry peanut butter mix.
Use a much tighter radius on the fillets where the panels meet at an acute angle (the keel at the bow and stern) than where they meet at an obtuse angle (keel under the seat). I change spreaders, with different radii, along the length of the keel usually at the bulkheads.
The other trick I do when making the larger fillet is to let the fillet soft set (2 hours) before laying down the tape and wetting. The fillets won't squish around and leave finger dimples. The usual method of taping over a wet thickened bead of epoxy is quicker and less effort but not as neat. It’s a matter of esthetics inside the boat.
Inspect the tape when the epoxy sets to flypaper sticky (won't come off on your finger but still is very sticky about 2 hours). Press down any bubbles and that nasty salvage edge, it will stay down in the sticky if you time it right. You can also rewet any dry spots at the same time because the fresh epoxy will still penetrate the sticky.
Always remove masking tape within 24 hours of epoxing or little pieces will be permanent parts of you boat but when used as a dam be sure the epoxy has at least a hard rubber set to avoid distorting the epoxy.
A gap at bulkheads is no big deal that is what fillets are for. At the tight spots the epoxy wicks through by the time it sets. The pressure of striking a fillet is enough to fill the gaps and the fillets are stronger than the wood. If the gaps are really big mask one side while you fillet the first side. The next day pull the tape and fillet the second side. It will look much neater than chasing the wet epoxy back and forth through the gap.
An extra half inch on the width of the shear is no big deal. Fair lines are the most important. The bending of the shear clamps help create fair curves. Sucking the shear in after glue up will make wows in the curve. If you are opposed to the extra 1/2 inch of beam then you have to shave the bulkheads or move them toward the cockpit a little if there is room.
Shave the shear clamps if they interfere where they end to remove the bulge at the ends. The easiest way is to cut through the where they touch several times with a pull saw until the shear is correct. Then glue the sawed surfaces on the shear clamps together with thickened epoxy. If they do not touch push the sides together with a clamp to the right position and glue the shear clamps together with a filler piece.
In Response to: West River 18 by Paul Buelterman on Jan 9, 2005