Lee wrote: I have a variety of composite structures that need to be filled. I have been using hardware store Bondo for this lately. It works well enough except it is way too hard, difficult to sand to a finish without boogering up the surrounding surfaces. It's also rather heavy.
There are 2 options, same fillers, different resins. Epoxy is great stuff, but if you have a poly resin to begin with, you can stick with poly resins, unless there is a critical adhesion issue. You will thicken the resins with micro balloons and a bit of fumed silica to prevent sagging. You keep the silica to a minimum or it gets harder to sand. You can use a lot of micro balloons in the mix if it isn't structural. I have used over 400% by volume to get an almost dry-ish mix that can be stuffed into major gaps. You work a bit more resin in to the top layer to get a smoother finish. This results in a light filler. Epoxies are more flexible and adhere better, but once you have epoxy on a surface you are stuck with using only epoxy there after. This isn't as important with small airplanes, but can make a huge $$ difference with large boats! Mark Mech (Back in the desert after towing a trailer through 3 days of California storms!) www.aerofoam.com RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off.
