RE: Vac Bag to fill weave?
Ed,
You may want to give this a try without dismissing the idea. I recently sanded down a V-Tail for a Q500 racers. Cut the mylar about 1/8" bigger than the tail and waxed it up. Put down a coat of primer on the Mylar and laid my glass (3/4 oz) directly on the mylar. Once its all wetted out on the mylar, you can scrape all the excess resin off. I then put my skinned hinge material (Kevlar) on the glass at the hingeline and then placed the balsa tail in the middle of the sandwich and threw it in the bag. By applying the resin to the cloth while it is on the mylar instead of the balsa you get no soak in like you would otherwise.
The finish came out smoother than I ever would have expected. You will need to sand the edges up a little, but I think you will be happy with the results.