>Do you spray these things (oil, Corrosion Block) on the outside of the body,
>or do you have to get underneath and do it from the inside?
>--
>Katherine Maas, MA, CPCC
>KJ Maas Associates Ltd.
>Transforming people and organizations through personal and interpersonal
>excellence
>P:    604-985-2245
>F:    604-985-5846
>E:    katherine@kjmaas.com
>
>"Learning is not compulsory... neither is survival."  -- W. Edwards Deming
>a

You need to get into any seam from whatever direction is possible.
Sills are closed members, so you'd need to drill the bottoms and
SPRAY the stuff in liberally.

Probably better to spend the money and get a professional
rustproofing job done, though I believe these guys only do the closed
areas (sills, chin, doors etc). This stuff remains fluid and can
penetrate (by capillary action) seams you'd have sworn were solidly
sealed with paint etc.

For seams which are not in closed areas (roof, aprons, wheelarches
etc) you'd have to do them yourself.

WD40/CRC 5.56-type products are useless, because they are extremely
thin and will run out and disappear rapidly. However they CAN be used
to mix grease with and carry this in with them. But better to use
motorcycle chain spray-lube eg CRC Tac-2; these are greases dissolved
in thin solvents, and will penetrate as well as WD40. The solvent
evap[orates, leaving the grease filling the cracks in the seam paint.

As far as accident damage goes, an impact at one end of the car can
fracture sealer at the other end. I T-boned a car which turned in
front of my very solid Nissan Skyline. The other car was a writeoff
an mine suffered only cosmetic damage to bolt-on components... and
seam sealing. After a few months rust stains were beginning to appear
under the seams in the rear door openings and rear apron (under rear
bumper).
--
Andrew Grebneff
165 Evans St, Dunedin 9001, New Zealand
<andrew.grebneff@stonebow.otago.ac.nz>
Seashell, Macintosh, VW/Toyota van nut