Took the SBU at TechShop and have access to vacuum former now. Cute little machine; ceramic heaters, 24" bed, will pull up to 30 inches of mercury (aka a pretty good vacuum). They stock small amounts of PETG there, maybe a little ABS (and Tap Plastics is right down the road). So that puts new kinds of plastic shapes in range for the next prop.
Same day, I tried out new ideas for Aliens M40 grenade forming. The longer base cut still didn't clear the knurling tool, so back to the 16 degree angle for that. Installing the spring from the top does work, but I need a different drill bit to get a tighter fit on the hole. Although I was able to make the first one work with a little JB Weld. Since there's not enough time to make an order at McMaster-Carr, I'll assemble the current grenade order the same way as the previous ones.
I still haven't figured out a good way to make the button "click." The latest idea is to mill a narrow slot down the button and slip a piece of spring-steel wire in there. I also have no idea how to get the cap to pop off with that lovely sound. There isn't enough air space to create sufficient vacuum when it is thumbed off.
Annoyingly, the AMC7135's haven't arrived yet (and there is no tracking from that supplier). So I can't try out my PCBs.
And today seems to have been doldrums. Just haven't gotten a lot done in either design work or repairs.