blast media

[Alan8n]

I am going to do small scale sandblasting on misc parts of my tractor to remove old paint / mild rust. Some are cast iron some are steel, some are sheet metal. Settled on using Balck Beauty / Black Diamond but can't figure out what grit to use. Local store only has 20-40 and I am told that it may be "too aggressive " and I should use 30-60.
I typically use the MP170 Epoxy primer (2 coats) and topcoat of various manufacturers with hardener( 2-3 coats).
I am not sure what "too aggressive" means too me. Does it mean I will get poor coverage, and need to use more primer / paint... or does it mean that I will just be taking off more material then I should ....or...???
Thanks....Alan
 

[CNKS]

The only thing you could possibly damage is the sheet metal, if that is true it is more about how close hold the wand and how much pressure you use. You aren't going to damage cast or forged etc. I doubt if either is more aggressive than sand. I usually go over my parts with a wire wheel, partly to get rid of any imbedded sand and partly to make it smoother, I really doubt if the "smoother" is necessary. No matter what you do the 170 coverage will be the same. That said, I usually use sand for the big parts outside, and have just recently used a black beauty clone in my cabinet blaster--I don't have a clue what the grit is.
 

[sflem849]

Have you ever tried a blasting basket for your small parts? One of the local pro restorers swears by it. He sold his cabinet and that is all he uses now. It sounds like an expanded metal basket and then you just put your smaller parts in there.
 

[CNKS]

Probably a good idea if you have some larger parts to blast with it. I very much prefer a cabinet. I don't have to use supplied air, it is inside out of the heat, cold or wind, and is not messy with sand all over the place. I wish I had a bigger one to put large parts in.
 

[Bodyman]

Alan, I have used black diamond for years with satisfaction but for sheet metal I think you can"t beat fragmented glass, with a little common sense and caution it is the Cat"s a.. in my book. Just my opinion and you know what they say, opinions are like a holes everyone has one and it"s most valuable to the owner. Happy blasting.
 

[fordhead1983]

A trick a buddy of mine showed me is get an old concrete mixer, throw your small parts in, cover with sand blasting media, and let it run overnight. I have yet to try it, but the results he showed me are pretty impressive.
 

[WOpp]

I us 40-60 grit, does a nice job. 80psi. A supplied air hoodn is nice for large outdoor work,
 

[Kurt_JDB]

I have had good results using "Blast Glass" from Northern tools. It is listed as 30-70 medium grit. Made fro recycled glass.

Soda blasting is the way to go for thin sheet metal.

Kurt
 

[JRSutton]

not sure about it being too aggressive - but in my sandblaster, the 20/40 black diamond clogged almost continuously.

using the largest nozzle that came with the blaster - could probably find larger if I tried - but instead went with a finer grit that worked well enough not to bother trying another combination.
 

[Brad Buchanan]

Hi Alan.

One of my first jobs was to sandblast newly assembled car carrier trailers (eventually became anchor clankers).

this was a large setup with full hood and cape with supplied air and a 'deadman switch' on the nozzle which looked a bit like a fire hose.

One of the employees brought a door in a car door and wanted to get it sandblasted. I told him that I had never blasted sheet metal but he insisted that I try.

I turned on the air and almost immediately blew a rather large hole in the door on the first sweep.

The abrasive used was 'black beauty' and it can be aggressive with high pressure air.

On the other hand I have recently blasted sheet metal from my 8N with a small gravity feed blaster with black beauty with no problems.

hope this helps,

Brad