This first practice layup is six BID plies onto a flat surface. I first taped plastic to the work table (about 24 inch x 24 inch) to keep the epoxy from bonding to the table top. Next I cut six plies of BID that were about 12.5 inches by 18 inches.
I had ordered the chapter 3 kit which included practice materials, hardners, and resins from Aircraft Spruce. What I didn't realize right away was that although they sent me the MGS epoxy system (which is fine), they mixed up the 285 and 335 systems. They sent me the 285 resin and the fast and slow hardners for the 335 system - these systems should not be mixed. Since this is a practice layup and not part of the aircraft it's not a big deal but I have asked AC Spruce to send me a new container of resin or the appropriate hardners for the resin they already delivered.
Carrying on, I wet each layer of BID cloth using a rubber squeegee and used the stippling technique with a paint brush around some of the edges where needed.
I let the layup cure for about four hours then I attempted to mark and knife/pizza cutter trim a 10 in. x 16 in. rectangle. I'm not sure whether it was due to the slow hardner I used and/or the mixup between 285 and 335 systems but the layup was clearly not ready to be trimmed it was still quite sticky. I trimmed the rectangle after about seven hours and I likely should have waited a little longer as there was some minor separation of the BID layers near the sides during the trimming process.
This laminate should weigh between 10.5 ounces and 12.5 ounces. This layup weighed 11 ounces which is just about perfect. Minor voids (white areas) near the edges were noticed and this was introduced during the knife trimming process which I expect to eliminate in future layups once I have the correct MGS system and ensure the trimming occurs at the right time in the curing process.
