If you have the room, good neighbors, etc., then check out your local rental place. A few years ago I rented a 100cfm diesel-driven compressor and 100# pressure pot. It was $60 for three hours, plus fuel ( maybe 4 gallons) and sand. I made no effort to recapture the sand, so approx. $40 in the wind. I did my frame, two fenders (an old military vehicle=heavy gauge metal), 4 wheels and various other do-dads in that time, which included bringing the compressor to the yard, set up, take down and delivery. Be careful, 100cfm @ 1?? lbs of pressure can wreak havoc on a chin when you carelessy turn on the valve, while loosely holding the nozzle in ONE hand. My chin grew back with no scars... and no rust!

 

I was wondering if anyone using walnut shells knows what grit they're using? The only place I've found crushed walnut shells is the local feed store...50# 12/20 mesh (grit) for $12. Bird folks use it for the bottom of cages. I've tried asking at building supply places, welding shops...no luck. The people at the feed store don't know much about blasting other than guys use it for polishing guns. Mel

 

I don't know what grind of walnut shell they use for blasting, doubt they get it from a feed store tho. Most of the hotrod shops have gone over to plastic media, non dusting so it's not a health hazzard, agressive on anything softer than aluminum (will blast the paint off an aluminum softdrink can without damage) including old bondo and rust but doesn't touch the underlying metal, doesn't absorb moisture so there is no packing or later moisture problems, easily vacuumed/blown out after. It's not biodegradable so you'll probably want to recover it.

 

Try this link for walnut shell blasting media. These guys supposedly pioneered the use of walnut shells on Navy ships. They could certainly tell you which of their grades they would recommend for your application.

Walnut Shell Link