Most industrial supply houses have 60 grit garnet or a suitable media. Harbor Freight even has sandblast media They have 80 grit glass beads, which I have used successfully, and a coarser 70 grit aluminum oxide media. Both are finer than 60 grit, so less aggressive.
I would start at about 50 psi and see how it works.


Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.