Don't know if this has been mentioned.
Gran Chillin', king of S&G, uses a dental syringe to form his filets,but for larger areas, use caulk tubes.
There are empty caulk tubes out there that you can fill with thickened epoxy to fill voids, make filets,apply to long pieces,battens etc.
I get mine from a fiberglass supply,much cheaper than West systems at West Marine,but I've heard you can buy cheap silicone caulk and just clean the tubes and reuse.
Mix the filler & fill the tube
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Tap down to fill and to get air out
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Apply to area
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Smooth off with radius tool and this is what you get
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I forgot to tape off the area beyond the filet...if you do, you will have less to clean up later.
After I use the epoxy, I tap the flat end cao out with a metal clothes hanger ,then stuff some vinegar wetted paper towel in the tube,turn it around with a paint stir stick, push out with hanger again and stick point end and cap into a container of vinegar.Finish cleaning after fileting etc.Tubes can be re-used.
Oh yea, very important to dress for success...a Hawaiian tropical beach shirt to give inspiration to the finished build....vision of umbrella rum drinks on the beach, palm trees bikinis,skiff at anchor!!!

Jimmy Buffett or other Trop Rock on the radio helps the build too!!
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