In a message dated 9/15/99 7:12:16 PM Pacific Daylight Time, Advdesign1
writes:
<< In a message dated 09/15/99 09:56:46 PM Eastern Daylight Time,
Passnb4U@aol.com writes:
<<
I agree with Grant on the process, but I'm still a little "old school" on
somethings, and would rather take the primer off to bare metal before
filler,
just a little more work that way, but give me a piece of mind.
>>
PPG and DuPont recommend filling over their epoxy primers for maximum
corrosion protection. I've seen lots of 20 year old filler with rust
starting under it on bare metal. Because filler is porus moisture gets in
and starts rusting bare metal. Epoxy sticks tighter than the vapor pressure
of water that is trying to push it off. I would fill over epoxy. I would
also use an etching primer immediately after blasting. As soon as you finish
blasting the steel starts rusting, so don't wait. Also brush primer into
overlapped seams so capillary action sucks it into the hidden part. Use
small nozle in blaster for flat parts. Have poerator give you a guaranty he
won't warp flat metal. You should be safe with silica and a 1/8 inch or
smaller nozzle if you keep it moving. I gave my prep and rpiming opinions in
good detail in THIS OLD TRUCK last year.
Bob ADler >>
Yeah, I agree, I've seen lot's of bondo cracks too form too much bonda, not
enough metalworking done. In the last several years the advances of both
filler and primers has come up quite abit to eliminate that, if prepped
correctly.
Now I'd think if the epoxy primer can seal the etchprimer and metal, it
would seal over the filler too, or are you saying that the filler is too
porous to be sealed adequately with the epoxy primer?
Thanks,
Mike
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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