I blasted the rest of the engine cover this weekend. It took about 2 hours to blast and about 100 lbs of media. I wound up reusing some of the media toward the end and it worked o.k. I have been told that slag only works once. It seemed to be just fine the second time around. I figured out that when the pressure drops at the pot, the blasting efficiency goes south pretty quickly. I spent quite a bit of time waiting for my 5hp 60gal blackmax to "catch up."
Bottom of hood blasted
Hood in DP90