Many years ago I used Cotronics Resbond 907GF in a OEM application and recently tested it for sealing firewall penetrations and holes.
The product exhibits very good bonding qualities and adheres well to stainless steel.
I tested the product by simulating firewall small hole plugging and bonding by "gluing" two pieces of stainless steel together. After curing overnight I was able to break the bond by prying with a screwdriver but was impressed with the strength as I did no prep to SS.
I exposed the cured product to a torch and heated the SS/ Resbond to red hot condition, I observed no smoke or odor and after cooling the bond was just as strong.
Based on my previous OEM use and recent testing, I believe this product to be ideal for firewall use.
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