Sandblasting

Just a quick question. How is it that guys are having their whole bodys sandblasted . It was always my experiance that panels would be warped all to hell because of the heat generated . Can anyone tell me how this is done ??? I always just used sandblasting on rigid pieces . Thanks in advance on this issue .

 

Gotta go carefully at a shallow angle, watch pressure.

 

it took about 7 hours to blast this one. stay back, like tman said, shallow angle, sweep back and forth alot dont concentrate on any area too long.

we used about eight 100lb bags of 80 grit sand. have a good inline filter. we used a gas powered IR screw compressor. sandblasting a body will kill any piston pump compressor i have seen

 

what pressure do you guys use ?

 

I've done a couple, hasn't killed mine yet...but it's an old two stage iron compressor, not a modern noise-maker.

A screw compressor is the way to go if you're going to do this on a regular basis.

 

I use black beauty (medium)at a good angle and move around alot to avoid heat. Did a 47 Chev tk in 31/2 hours with 6 bags and not one issue with any panel. Just don't get carried away and too aggressive and you should be ok.

 

Warpage comes from heat. you can blast all day and as long as you spread out the heat buildup and allow the metal to cool between p***es there will not be any warpage.
As long as you spread out the blasting using long strokes, the media and pressure do not effect warpage. Only heat does. The pressure and media will determine how fast you have to move to keep the heat down.
Moving the blasting point back and forth over a wider area dissapates the heat buildup better and allows the metal to cool between p***es.
Foe wexample, When I blasted the bedsides on my PU I made a p*** at the top down the entire length of the bed. Then across the middle. Then across the bottom. repeat and drop down slightly until the area is clean. You get the idea? By the time i got back to make a second p*** on the top row the metal was stone cold to the touch.

Use your bare hand to just make certain that the metal remains cool to the touch before and after each p*** and you will be fine.

 

.....Angle is important and go slowly ,,,try not to stop in one area.....no heat......plan on about 5 hours to do a complete car....37 Ford coupe

 

Use a tapered nozzle as opposed to a straight nozzle, it spreads the "spot" out, to reduce heat build up.

 

I don't have any idea of how many hours it to to sandblast the wagon but I blasted every piece inside and out,,frame and all suspension parts.



33/100 lb. bags of sand and my compressor never complained,,as everybody else pointed out,,keep moving and don't concentrate in one spot too long,,shallow angles and you will be fine,,,oh yeah,,and a high quality respirator,,don't skip when it comes to protecting your lungs.

 

Will sandblasting also remove bondo?

 

yes, but its tough. on mine i took a 7" sander with 36 grit to get most of the bondo out, then just dusted the rest off with the blaster.

 

Yes it will.HRP

 

Warpage is a concern on all body sheet metal, but heavily contoured or curved panels will take more heat. Flat door skins and the like are the major concern for warpage. If you can, use a sander and or paint remover on the flat areas, and save the blasting for tight or hard to get to areas and rust.

 

I don't see why its not used more often. I'm more puzzled when I see people grind off paint, doesn't that cause heat and metal damage?

 

Blasting also can impart stresses into the metal and/or relieve stresses already in the metal, resulting in distortion.