I’m working on a pocketship and I’m at the point where I"m applying fiberglass tape to the upper side panels. These are vertical and I’m concerned that when I apply epoxy to “fill the weave” it’s just going to run down. Tipping the boat on it’s side is not an option here.
I’m wondering which option would be best -
- Apply multiple very thin coats and tip to remove runs. I suspect this would take 4-5 applications at least.
- Use Cel-o-Fill to thicken the epoxy a bit - maybe to mustard consistency.
Suggestions?
Very thin coats are a good way to go if you must fill the weave with unthickened epoxy, as for bright finishes.
If you’re painting that part of the boat, fill the weave with frosting consistency epoxy/phenolic microballoon mix instead of mustard Cel-o-Fill. It won’t run, or hardly run at all, it’s lighter than Cel-o-Fill thickened epoxy and you can put on a thick enough layer so that you’ll be filling the weave and prepping for fairing at the same time.
Microballoons have have better strength in compression per unit weight and are much easier to sand than Cel-o-fill. They have inferior shear strength but surface finishes don’t need the level of structural strength that joints do.
- Save filling the weave with epoxy for bright finishes.
- Save Cel-o-Fill for fillets
- Use phenolic microballoons for surface finishing
Laszlo
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Yes, keep the coats thin. Even fiberglassing a kayak has the same (though smaller) problem of vertical surfaces when doing the hull. I squeegee and brush my initial coat and (mostly) brush on the fill coats. I find it’s helpful not to just walk away after applying the epoxy, but to keep checking the epoxy to catch sags and runs and brush them out. Depending on temperature, after ten minutes or so it will stop moving around.
If it’s a flat area, and the Pocketship has many verticals that are reasonably flat, you could use Peel-Ply, though I didn’t use it much on my Pocketship build.