Seems like the right thread to show my PLA mold attempt.
This stab may be the first usable thing I've built.
I designed the mold in Fusion 360, sprayed it with sandable primer ( not sure if this was necessary) , waxed it, filled the mold and squeezed the mold together.
Next time I think I'll build the mold upside down so that the more curved part of the wing is the bottom, so gravity will help fill it.
Also, my alignment dowels in Fusion were not exact enough so they just got in the way. The wing plug I did before with out dowels came out better, so I will leave them off next time and just align the outside edges of the mold.
This stab was about 1/3 inch thick, it worked no problem.