Hi Frank,
I used POR-15 directly on my TR4 chassis and the stuff is nearly bullet
proof.
The only POR primer I've seen is intended to go *on top* of POR-15, as
preparation for certain finish coats that might be painted over it.
No need to prime *under* POR-15. "POR" stands for "Paint Over Rust", so
little preparation is supposed to be needed. Just knock off any loose rust and
sand things a little if you wish. I media blasted my frame, but was doing a
lot of welding on it prior to painting.
POR-15 is thick and dries slowly, so it partially levels out and hides
imperfections. It brushes on pretty well, too.
After the POR-15, the TR4 chassis got several coats of Chassis Black,
without any primer in between. A top coat is necessary because UV will discolor
POR-15 pretty quickly. (Yes, even *under* a car, in case anyone wonders. I've
got PRO-15 painted inside motorcycle fenders and it yellowed in less than a
years time even though the bike is securely under a cover most of the time and
the insides of the fenders never see direct sunlight... at least so long as I
stay rightside up on it ;-)
Today POR has a new Hard Nose UV safe paint that I'd serioiusly consider
rather than Chassis Black. It sounds more durable and I've heard good
feedback from several who have used it. Chassis Black is okay, but it can be
scratched and knocked off a little easier than I like.
My biggest concern is that should I ever want to remove the POR-15 it
will be *major* job. As an experiement, I tried sandblasting some cured POR-15
with very little effect. Best way to remove seems to be with a welding torch!
(Don't ask me how I know!)
I would vote for body color under the fenders, perhaps with modern
chip-proofing under it if you don't mind a little texture. For one, body color
was
used by the factory and just looks right. Years ago I sprayed black
undercoating under the fenders of my TR4 and never really liked the look. And
there is
the UV issue with POR-15.
Hope this helps with your decision!
Alan Myers
San Jose, Calif.
'62 TR4 CT17602L
Looking for a collective opinion
por-15 use on the chassis, with or without the recommended undercoat? Only
prep work will be a power wire brushing.
what about under the fenders? por or body color?
thanks
Frank
58 TR3
well into the restoration now, and feeling the muscle pain of it too!
|