My cabinet is full of glass bead. On aluminum it's perfect, but it doesnt cut very fast on paint or rust, it just takes longer but there's less pitting. In the portable blaster I use a medium grade black beauty which will strip like none other vs the cost of it, but will do some damage if you use high pressure, it pits pretty bad. If you're just starting out, start small. Do some stuff that doesn't matter if it gets wrecked. You will waste some media, but you need the practice AND patience. The best thing to do is start with a cabinet and do some small stuff, a decent enough cabinet can be had for about 300 bucks. And yeah, you need a good compressor, a two stage is what's preferred for that. It uses more cfm than most anything else you'd do with a comp.

 

So say i decide to scrap the sandblast idea and just use sandpaper, is 80 grit the correct grit for the body panels? Is a random orbit sander ok for the job?, do i need to worry about warping the metal if i push too hard down with the sander even?

 

Do not sand blast sheetmetal...I have looked at many cars that were ruined by sandblasting. It will ripple and distort the metal and the panel will look wavey when painted. Plasic media is very popular and will not cause excessive heat buildup on the surface like sand will. I hear that using baking soda is the new technique...it can be used on a car with the glass and weatherstripping in place and will not damage them but will take paint right off...unfortunately it is expensive.

 

yeah go with 80 grit on a dual action sander!

 

anybody else heard of using crushed walnut shells? Or any other type of nut/grit material? We have a body shop across the street from my work and I talk with the guy quite a bit - he mentioned that anytime you take a 40 year old car down to the metal, the whole car will be wavey and he has to basically do alot of block work to get a straight surface. He mentioned just using a DA to get down to the metal/smooth surface as probably being good enough to form a surface - when you sand down, you will notice that you get to metal earlier in some places than other so just get down to where you are still straight but metal in some spots (this would depend on the car - ideally, you would be all metal and perfectly straight, and then you woke up)

I am getting ready to dive into the fenderwells and underbody on my 66 - luckily I am in CA and the car is pretty straight with no rust

 

the car will only be wzy if its wavy b4 u start(unless there is problems under the paint! if u keep the da flat and u dont dig any ditches in the paint ull be fine but yes blocking it makes for perfect. most old car people restore have dead paint and faded paint will not show dents etc if u get wet the car it will show u more of what it will look like when u get finished!

 

Usually you would use walnut shells for blasting any interior engine parts, or similar things. That way if there is a residue, it won't harm anything once it is put back together. I wouldnt want Silicon Carbide in my engine oil.....