So I changed my mind. Added a second coat of epoxy to the inside surface of bottom #1. This surface will be the one that gets stitch-and-glued to the sides and frames to construct the hull and the frames had been given two coats, so I matched that.
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| This picture shows the sanding half done, the left side covered in dust. |
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| Shiny |
The first part of this epoxy layer (on the left side) came out good, the later part on the right ended up with some air bubbles trapped in the cured epoxy. I'm guessing that it was temperature related. It took an hour to do the whole thing and the air temperature rose a fair amount in that time (10:30am to 11:30am). Also, the foam roller gradually fills completely during the process and the epoxy in it begins curing. Being an exothermic reaction, the foam roller gets quite warm and it may have given the epoxy a boost of heat as it was rolled out making it cure faster. I think the first part had a longer cure time and had time for the bubbles to rise out and the epoxy to self-level more than the later part. I mixed three batches of epoxy to complete the coat, so it shouldn't have been the batch curing time. It had to have been that the later batch was put down significantly warmer. Just my guessing of course...
I also did three things prior to setting the bottom pieces aside.
- I drew lines on the inside surface marking where the frames will be positioned.
- I aligned the two layers and drilled two 'alignment' holes. When it comes time to laminate the two bottoms together these will be used to quickly align the two layers. One layer will get a coating of glue, then I'll put dowels or pegs of some sort in the holes and lower the other layer into place perfectly (nearly) aligned.
- I also pre-drilled the second layer with a grid of screw holes. Once the second layer is set onto the glue it gets clamped down with screws. Lots of screws. 90 screws in fact. Although that sounds like a lot, the screws are actually spaced 12 inches apart.
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