Guys
There are several alternatives to sand blasting. For frames, axle housings, and other heavy parts, try high pressure water blasting. In my area we have a couple of industrial cleaning companies who use VHP (40,000 psi) pressure washers. I use them to blast the overspray off paint hangers and conveyors. The 40K unit will strip 2" of cured 2K urethane as fast as you can move the wand. They have been used to strip concrete truck frames down to be repainted. This process removes everything, paint, grease, and rust. As soon as it is dry, you hit it with some metal prep (phosphatizing compound) then prime. If you find a local company that has a blast booth, you could roll in a deuce frame assembly and have it cleaned up in about 2-3 hours. It removes no metal, just rust, paint, grease, etc.
For sheet metal, you can use dry-ice blasting. This is similar to sand blasting, but uses small pellets of dry ice. The thermal shock takes paint right off. The best thing about this process is it does not thin down your sheet metal like a sand blaster. The down side is it does not remove rust very well, in my experience. This is used in the aviation industry to strip aircraft. I saw a video of the original 707 prototype being blasted. When the job was finished, they swept up 2 or 3 barrels of paint chips. No damage to the metal, no stripping chemical waste.
There are also chemical strip companies. They use a large tank of hot caustic stripper to dip your parts. They are usually used to strip paint residue from painted parts that have cosmetic defects, so they can be repainted. They are also used to strip paint racks. There is a company in Atlanta called Eco Clean that can strip a pickup cab. I believe UnPaint can also handle an object that big.
Sandblasting is a good method, but like any process there are pro's and con's. Sometimes the price of a professional strip job looks high, but if you are buying sand, paying the electric bill for the compressor, or just too impatient to take all the time, there may be alternative methods to use.
If you live in an area where there is a good sized manufacturing base, there will probably be some paint stripping companies. Check them out, you may find some surprising alternatives to sandblasting.
Regards to All
Robert Miller