[Healeys] Dipping vs Blasting

[Peter Svilans]

Chemical stripping costs more but overall you get a more thorough job of
rust-removal. Immersing a rusty chassis in a fluid means the chemical flows
into and through all the spot-welded flanges (well, mostly), and closed box
sections.

Media blasting only cleans off the areas to which there is direct line-of
sight access. You won't get the operative, who's thinking about lunch,
clambering in and out of your chassis with his blast hose just to get at those
inaccessible nooks and crannies.

Many offer a prime-and-paint service, and once the chassis is in shiny paint,
those rusty corners and flanges are out of sight out of mind. At any rate, our
modern primers will keep the rust at bay until the warranty runs out, right ?

No, the chemical dip is not perfect. The better companies stand the chassis on
end and flush the insides with a neutralizer or water from a running hose for
several hours or overnight. But there is still a chance of those orange
cauliflowers appearing in unexpected places. But the metal guys prefer to work
with clean metal, and not spend a lot of time opening up and hand-grinding
rusty spotweld flanges. And the industry's operatives themselves aren't
necessarily NASA material either. One of our bodies was left in the tank
overnight, invisible, and the night shift dropped another car on top of it,
crushing the roof.

Dip strip places are fast disappearing, being chased out of town by the
environmental brigade. Lots of beaurocracy. Our stripper had a wall covered
with government inspection certificates. Even the chemicals themselves are
less effective, the bio-based materials being less agressive than before. The
dip-strippers are fighting an uphill battle, and along with the plating
houses, won't be around next generation.

Best regards
Peter