Classic/Antique Car Repair: media blasting, cubic feet per minute, canal boats

Question
Brian,

I know this isn't exactly up your alley, but haven't found any bulliten boards on auto restoration and air compressors.  And I'm thinking with your jag experience, you have alot of body work experience.

Any thoughts on air compression systems for blasting rust off body parts & frames?  I have been in the market for an air compressor for some time now.  I know the key is running horse power (as opposed to start-up HP) and cubic feet per minute (SCFM).  

What I am finding though is huge price increases when I get up into the 18+ CFM range ($800-$1000) as opposed to $500.  All the industry sources suggest media blasting requires 18-22CFM, but they all seem to have a professional in mind.

If I am a hobbyist, do I really need 14CFMs for media blasting?  Can I get by with say 11CFMs and a bit of patience!  Thanks for your thoughts.

Answer
Hello Jack,

it really depends on what you want to blast.

You can get by quite well with a smaller compressor for small items, preferably inside a cabinet.

We would take our vehicles to a professional shot-blaster, once we had stripped and removed corroded panels. They were also able to spray the cleaned shell with a basic primer, to prevent the vwhole shell rusting overnight. The metal is so clean that moisture will soon get a grip...!

We would sand or strip the primer as we repaired sections of the metalwork and then re-prime.

We also have mobile units in UK which can travel to a location and conduct the work on site. These are very popular with steel canal boats/barges needing renovation.

I would recommend either of the above for a complete bodyshell/frames.

If you decide to build a simple cabinet, use a filter on the exhaust side of cabinet to prevent fine dust escaping and you. or others breathing it in.

You will also need a good internal light, with a glass cover, (jam jar?) to prevent bulb breakage.

I built one of these and we used it on small items, (lots of them), and if you use glass beads instead of sand, you can clean aluminium parts, carburretor bodies etc..

T^he compressor we used was a standard unit which provided air for spraying and normal air tools. It worked fine :-)

Hope this helps?

Brian
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