The plans say three hours. I allowed six. It took eight. At least it's done.

This was a messy step for me because I got interrupted by an emergency at work. I ended up having to save a portion (glassing the area between the firewall and rear LG bulkhead, and installing the UNI reinforcements) for later, which was a mess because some of the glass pulled away from the firewall/bulkheads as it cured.

Before it was completely cured, I used some clamps and boards wrapped in plastic to force the edges against the firewall and rear bulkhead. Unfortunately, THIS caused a crinkle where it wrapped around, which reduces the strength of the layup. Fortunately, it didn't happen around the reinforcements, so it shouldn't cause too much trouble. I'll fix it later, when it comes time to build the fear cover.

I also learned a valuable lesson about layup quality. I only used peel ply where the plans call for it - along areas where there will be future joins (for the sides and around the bulkheads and firewall) and anywhere there was a current join (between the pieces of UNI). Well, those areas look great, and the rest is mediocre. There's no problem with the actual workmanship, but the areas that I used peel ply on look a lot better. I know this is going to get covered up in finishing, but it also means more sanding later, when it comes time for that step.

From now on, I will peel ply everything, unless it's totally irrelevant. I have a 38-yard roll of 60-in wide peel ply, and I'll order another shortly. This stuff seems expensive at first. If you order it from an aircraft supplier it costs almost as much as fiberglass cloth. However, you don't use nearly as much of it as you use of the fiberglass, so its cost impact isn't all that significant. You can also get it on the cheap from fabric supply stores, if you know what to look for.

There is a great debate about the "sizing" that manufacturers apply to the cloth you'd find in a fabric store - some say this can leach into the layup and weaken it. I have some doubt as to whether this matters. Even a weak layup is still immensely strong, and you don't use peel ply between every layer. I tried a few tests with store-bought stuff, and while not very scientific, I couldn't detect any significant strength difference. I suspect the difference is probably a small or moderate effect, and you get a better bond between layups that have been peel-plied than you would if you had sanded them. Since sanding is also an acceptable joint prep method, I suspect this probably works out close to even in the end. Oh well. I have the funds to stick with aircraft suppliers, so I'll do that just to be on the safe side.

Word of caution. If you do go with stuff from a fabric store, buy some real peel ply first, to compare it. The stuff I first bought was much too gauzy. Real peel ply is thick and dense enough that you can't see through it. Think of a white cotton bed sheet, but made of polyester.