You can't get into the rust pits and cracks between 2 metal pieces with sand
paper. Usinf a home air compressor doesn't generate enough heat to harm
auto metal. Yeah if you use a blaster meant to do bridges maybe. Media is
for alloys - like cylinder heads and alloy wheels. Try by hand but each pit
that you miss will bring back a paint bubble in 9 months or so. If the
metal is folded over there be sure to seal the seam with body caulk (3M or
Aveco are popular brands). If you don't care how it looks and only want to
stop the rust use POR-15.

"jjs" > wrote in message
...
>
> "Wolfgang" > wrote in message
> news:9x1xd.12305$7p.9970@lakeread02...
>> Sand blasting works to get all the rust (protect glass and surrounding
>> areas),
>
> Ya know, I read that a lot and maybe you should qualify it with "light
> blasting" or "media blasting" with something other than sand. Sand
> blasting can create a lot of heat and weakened steel. It's not such a
> large area that handwork won't suffice.
>
>