I am building a Great Planes RV-4 and am at the point that I need to finish the seam made by joining the two cowl halves. I have some microballoons coming but was wondering what to mix them with to make a putty-like filler to finish that seam? It seems epoxy would be pretty gummy to sand properly, TiteBond might be OK, don't think CA would work. canopy glue maybe. What would be best to make the filler and what proportions of balloons to adhesive do I use to make a workable putty? Or can someone recomment something better for the job than microballoons?
Max