Hi guys. There's a real interesting article on this very subject on Autobodystore.com. Here's the link to the tests they did regarding epoxy vs bare metal under filler.

http://autobodystore.com/filler_&_epoxy.shtml

They have a lot of info on their site as well as a forum to ask questions. Hope this is useful

pat


1952 Chevy 1/2-Ton
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