Fox Media Blasting Parts For Paint

[adumb]

i have a fair amount of small parts i want to media blast and then paint. i happen to have a bunch of black beauty coal slag media that was left from the previous owner of the house and garage. how do i know what grit this stuff is? they have three different grits on the website but i can see if say anything about that on the bad. these bags could be 15-20 years old so maybe back then they only had one kind?

it seems to clean the metal off pretty easily. what happens if i use to harsh of a media? i plan on painting these parts with the black spi epoxy primer. do i just blast them off with air after and then wipe them down with a wax and grease remover to be safe and then paint?

I would hate to blast all my parts just to find out i ruined them.

thanks
adam

 

[grnhays]

Coal slag will come in sizes from cat litter, down to sand. If your pieces are heavy enough steel, you wont ruin anything.

Remember if you are using a coarse grit for blasting, make sure you put enough paint on your pieces. A coarse grit will give you around 4 mil anchor profile. Meaning, you are going to need at least 5 mils of paint to cover the anchor depth. Most epoxys will call for 4-8 mils wet, minimum. You also gotta consider 4-8mils wet, will be 3-6mils dry. Depends on the make up of the paint.

In other words, if its coarse, make sure to give it a couple good coats of paint

 

[Davedacarpainter]

If it's small parts you'll be fine, what kind of parts?
Don't use it on any surface panel (door, fender, etc...) . It will warp the metal.
An epoxy primer won't require an acid etch undercoating either. Fact is, epoxys shouldn't have any sort of etch coating used before them, it's bad for the primer.
+1 to the wax and grease remover after you blast them.