Rich, et Listers,
While I agree that using plastic or possibly walnut shell media is much
safer, glass bead media can be used without removing any aluminum. At one
point in my career I worked with Firestone in Akron, Ohio and had the
opportunity to see tire manufacturing up close. The aluminum tire molds are
cleaned periodically using glass bead blasting. They are carefull to keep
the air pressure below a critical point where the beads break up, at which
point the sharp edges of the broken glass start cutting away at the
aluminum. I think they said this pressure was around 40 psig. Below this
pressure, the beads just peen the aluminum; i.e., moving it around some,
but don't cut it away. Having said this, I still would never glass bead
blast anything I planned on putting inside my motor.
Bob
At 09:19 AM 12/10/98 -0800, Rich Atherton wrote:
> Well, the last time I checked, Hot tanking (Hot Special Solvent bath at
>automotive machine shops) will eat aluminum. Cold Tanking (different
>solution, similar to carb cleaner but stronger) as it is called, works very
>well for aluminum. Some bead blasting may still be required if the powder
>coating was realy well done. WARNING. Use ONLY Plastic beads for the
>blasting. They will not damage te aluminum, and are far easier to remove in
>the final blow out/ wash out cleaning procudes when you are done. Glass
>beads are harder than the cast aluminum, and they can and WILL damage any
>aluminum surface they are blasted on. Use ONLY plastic beads....Takes
>longer = No Damage !!!
>
>Rich
Robert L. Palmer
Dept. of AMES, Univ. of Calif., San Diego
rpalmer@ames.ucsd.edu
rpalmer@cts.com
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