Posted by DAvid on May 12, 1999 at 07:39:18:
To those who inquired and others: I have used fiberglas
finishing resin to treat rust for years and have found that it
stops rust cold. I have brushed it on and poured in into hard
to reach places and have never had the rust come back. The
best way to use it is to remove all the loose rust/dirt mix up a
small batch at a time, then using a throw away paintbrush, pour
the catalysed resin on the surface to be finished and spread it
around. It can be poured into body braces, like the ones which
originally contained wood under the floors on command cars, and
into the bottoms or doors and the insides of windshield frames.
It dries to a hard, slick sandable and paintable finish. I have
repair & coatings which have lasted over 15 years on both the
out sides and inside of body panels.
Note: It is necessary to get the area as clean as possible & DRY!
It won't stick well to grease or water and may eventually
flake off or loosen an form a water HOLDING pocket: meaning more
rust instead of less.
Do NOT use laminating resin. It remains tacky and absorbs
water because it is air inhibited, meaning that as long as it is
exposed to air, it doesn't harden.
I have been told that the later polyester resins are better than
the earlier fiberglas resins but are harder to find. Bigger
paint stores will usually sell one or both.
If you have holes to fill, mix in some of the powdered glas or
use a piece of cardboard or masonite/panelling-backed cloth. Wet
the inside of the area well with catalyzed resin the hold it in
place until it gels. This stuff heats as it cures, so expect it
to get hot to the touch! After it starts to harden. coat the back
of the wood/masonite/cardboard also to keep the water out of it.
Unlike 'bondo' or welded-in patches, this stuff will not ever
rust out again.
Caveats:
Wear heavy rubber gloves and respiratory protection
when working with the glas cloth and powder and expect to get
drips on the floor/ground. I have decopaged papers to the drive
ways at several houses. (Hmmm! what was happening here in 1976?
Lets go read the driveway...)
Catalyzed resin waits for no man. When its mixed, its going
to harden. Be ready to work before you mix it up.
Remember, this stuff gets HOT! surgical gloves don't insulate
well unless several layers thick.