V12 Construction
Wet fillet & seam
I used 2 types of glass for the fillets: a heavy biaxial (it has the red line in it) 7" wide and a thin 3" wide unidirectional. I found that my technique for filleting has improved dramatically. But because of my technique, I'll never be able to do a clear coated boat. I really like the inside of the boat to be as smooth as possible with very symmetrical inside rounding. You may not agree with my method, but I find it very effective.
1. Make a thick fillet compound of epoxy, wood flour (in this case West System 403) & silica.
2. Put the fillet mix, after it is stirred, into a zip-lock freezer bag, and cut the corner of the bag off so that I can use it like a pastry bag.
3. Squirt
the fillet material into the seam in one continous bead. I then let it
turn green.
By this I mean that the bead of epoxy is starting to harden. It isn't
tacky, but it is still malleable. The window is very small for this state.
At 70 degrees, no sun, this can be only 10 minutes at times.
4. I then
take a 2" paintbrush in which I cut the top third off of it and take
some unthickened epoxy and form the concave for the fillet.
This is why the fillet material appears uneven under the fiberglass in
the above photo. The main part of the fillet fills in to make a strong
structural part of the seam, but the excess fillet material tends to spread
around unevenly. Once the tape is then placed over the seam, I'm able
to use the brush and a plastic roller to create a near-perfect and even
concave finish that needs very little sanding. It may not look great now,
but once it is opaque from either the purple-ish microballon filler and/or
primer, it looks very even and professional.
5. I then use a Sur-form to cut the edge of the cloth down.
