Hi there, My first time to lay fiber glass fabric on top of a epoxy sealed blank. I did tape off before glassing. Its quite hard to trim along the taped area since I using 6oz e-glass fabric. Until the epoxy cure completely, I cut off the tape paper and used a metal file to level the uneven area. My question is if I do it in a foam blank without treatment, the metal file probably hit the foam core leaving gorges and cracks. This must be someone got the same experience. Thanks Crabie
Next time don’t epoxy the foam before glassing.
Why? > Next time don’t epoxy the foam before glassing.
You don’t have to seal the blank with epoxy resin first (some just use spackle, some use both). If you do a free lap you don’t need any tape during lamination. The fiber glass cloth you are using should be silane, and should be clear after the resin kicks. Cut laps are normally used when you are using volan type cloth, which has a green tint to it when saturated with resin or when you are doing a fabric inlay on a board and you want to line up your fiber glass lap to your fabric inlay cut. When doing a free lap, you don’t have to come back and trim the lap, you just have to be sure to get the edge of the lap smooth and flat on your blank. As far as what to use to grind down you laps, there is a thread on the BB right now on it. Some use an angle grinder, file, DA palm sander and so on. I just use a file, or a small automotive angle grinder (I think that is what it is called, it looks like an L with a sand paper disc about the size of a quater and is nuematic). You just have to be careful next to the foam. If you are sealing the blank with epoxy resin you want to do a tight/thin layer on the blank and then laminate to it within 24hrs. of it kicking. Any time you wait longer than that you run the risk of the epoxy lamination layers not sticking to you epoxy sealer coat. This is why you need to skip sand your laps when laminating and then skip sand the whole laminated board before adding your sanding layer. Good luck.