Chemical Immersion The pros and cons
Ijust started a thorough, body-off res- toration of a 1960 Triumph TR3A and thought I would share with you the
many advantages and disadvantages that
I learned firsthand of having the body
chemically stripped, as opposed to blasting it with sand or other media.
Before I bought the car, the previous
owner had just finished stripping the
paint off the main body shell when he
suddenly died. Then the bare steel shell
sat for about two years; a light coating of
sand-like rust had formed. Some sections
looked like they had been removed with
paint stripper, yet there were traces of
sand throughout the structure.
Seeing that it had already been sandblasted in spots, I didn’t want to have it
sandblasted again for fear of removing
too much metal, so instead I opted to
have the entire body chemically dipped.
The chemical immersion process has
many distinct advantages as it doesn’t
harm the metal or thin it like sandblasting does, and it removes paint and rust
in places that the sandblasting nozzle
just won’t reach—but therein lies the
problem with immersing a car body in
chemical stripper.
For $800, the TR’s inner structure was
dipped—this did not include any outer
body panels or the chassis. To save money,
I’ll be media stripping the small doors in
WORDS AND PHOTOGRAPHY
BY RICHARD LENTINELLO
had some minor rust showing, so
those areas I either worked with
a wire wheel attached to my electric drill or with my pneumatic
grinder using 2-inch abrasive
discs. After the metal was perfectly
shiny and free of all rust spots, it was
wiped down a second time with Prep-Sol
and then sprayed with two coats of PPG’s
DPLF light gray epoxy primer mixed
with DP 402LF catalyst.
Not wanting to leave any of the freshly
cleaned metal bare for long, first I cleaned
and primed the rear body section, and the
next day I repeated that process on the
front half of the body, including the firewall and rear seat floor pan. Then I did the
underside of the scuttle followed by the
driveshaft tunnel. But making sure that
the epoxy primer fills every hidden cavity and every square inch of bare metal
behind every inner structural panel, like
those adjacent to the rear quarter panels,
is more difficult to do than I had realized.
It’s basically impossible for the spray
gun to reach some of these inaccessible
areas, but because the chemical stripper
goes everywhere, all this hidden-from-view bare-metal steel must get primed to
prevent rust from forming. To reach the
bottom of the B-pillar, I used a long artist
brush and brushed on the epoxy. Perhaps
a bug sprayer with a wide-pattern spray
nozzle will be able to spray the primer
everywhere, but I haven’t tried that yet.
So although immersing the body
involved way more post-stripping hand
labor than I first realized, I still believe
that the end result will be well worth the
effort.
my blasting cabinet and then using air-
craft stripper to remove the paint from
the fenders and hoods.
I thought that when I had the cleaned
body shell home, all I had to do was wipe
down the freshly clean steel with Prep-Sol before applying a protective coat of
epoxy primer, but that wasn’t the case.
First I had to scrub down the steel with
a Scotch-Brite pad dipped in MetalPrep
metal conditioner in order to remove
light traces of rust that formed when the
heavy application of metal conditioner
that the shop sprayed onto the body was
allowed to air dry instead of being wiped
off. Several adjoining panel seams still
