During this test we tried several different PSI settings to remove powder coat.  The goal was determining cycle times and whether increasing pressure would significantly change the surface finish. We used an Empire ProFinish Cabinet with 100 grit Aluminum Oxide, 5/16” suction gun to blast a 66.5 square inch piece.  Here are the results from our trial:
Suction @ 50 PSI:
Total Blast Time: 11 minutes 19 seconds
.097 square inch per second
10.3 seconds to clean a square inch

Suction @ 70 PSI:
Total Blast Time: 10 minutes 19 seconds
.1.07 square inch per second
9.3 seconds to clean a square inch

Suction @ 90 PSI:
Total Blast Time: 4 minutes 24 seconds
.251 square inch per second
3.9 seconds to clean a square inch

EXTRA TEST:
Pressure Cabinet @ 80 PSI
Total Blast Time:  1 minutes 6 seconds
1 second to clean a square inch

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