Charlie Kuss wrote:

snipped

What is the best kind of abrasive to use on aluminum?
Walnut shells or something else? They had glass beads
and aluminum oxide powder at HF.

Paul
 Back in the 60s, VW had numerous failures in overhauled Beetle engines. It was
determined via oil analysis, that the abrasives (glass bead, sand/metal oxides)
were contaminating the oil and destroying the engines. These abrasives would imbed
themselves into the soft aluminium during cleaning of the parts before overhaul.
After assembly, the abrasives would be released when the aluminium expanded during
operation.
 VW switched to crushed walnut shells (cellulose). The failure rate of overhauled
engines dropped down drastically.
Charlie Kuss

That is what I was leaning towards.

Paul Lamar
 
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