Blasting Media - Suggestions Wanted

[DeesZ]

I recently picked up a blasting cabinet and wish to know what media y'all have had good luck with. It's a Snap-On unit (made by Dee Blast), large enough to do wheels, cam covers, etc. I'll be doing a set of wheels soon (Western Turbine 2) as well as whatever else I take off of the car that needs freshened up.

I've researched and pretty much decided to go with two varieties of media 1) glass beads for 'finishing', and 2) aluminum oxide for when I need something more aggressive. (Some places sell mixtures of the two as well.)

Do you have any recommendations here? What media that has worked well for you? And what 'size' or fineness produces good results?

I'm wide open to suggestions....

[moonpup]

The following may help you decide what's best for your particular application. Glass beads & aluminum oxide are what I'm currently using.

http://www.nortonsandblasting.com/nsbabrasives.html

[Zs-ondabrain]

you've pretty much got it down. Aluminum oxide is great for rust, paint removal and the such. I use the Glass bead for cleaning aluminum nicely but it takes alot longer to remove the tougher stuff.

So I have 2) cabinets. One with Aluminum Oxide and the smaller one with glass bead. I run about 100 PSI on both.

[kurtwwalters]

For valve covers, glass beads would be best? I will be getting a blast cabinet from Harbor Freight next week, so I'll be buying media too.

[moonpup]

For valve covers, glass beads would be best?

That depends on what finish you ultimately want for the valve cover. If you're attempting to clean the cover via blasting with the intention of eventually polishing it, you'll just be creating alot of extra work for yourself. (Trust me, I made that mistake)

However, if you want a nice satin/matte finish, then glass beads do an excellent job. For ease of maintenance, you can spray the finished cover with a coat of high heat clear. Be aware though that the clear will darken the final color somewhat.

[Art@NissanSport]

Copper slag is excellent. Zero dust and very reasonable in price.

[d240zx2]

Walnut hulls are good, too. They're light in weight so their velocity is greater than, say, glass or AlO2. AlO2 can scar a part if you're a bit careless and I'd also suggest a real fine grit size for this media.

FWIW

Frank

[DeesZ]

Thanks for the input, everyone....

This generates another question... What media should the 'final' blast before attempting to polish... say a cam cover? I was thinking very small glass beads, but now I'm not sure.

Also, any recommendations on the 'grit' size for the media? I'm assuming "the smaller the better" for the smoothest finish....

[moonpup]

....snip....This generates another question... What media should the 'final' blast before attempting to polish... say a cam cover?...snip....

Most blasting media will peen/mark the surface (albeit uniformly) especially on soft metals like aluminum thus causing more labor (think lots of sanding on your part) just to get back to a point at which you started with.

If you wish to polish an aluminum part, keep it out of the blast cabinet.

[EScanlon]

Most blasting media will peen/mark the surface (albeit uniformly) especially on soft metals like aluminum thus causing more labor (think lots of sanding on your part) just to get back to a point at which you started with.

If you wish to polish an aluminum part, keep it out of the blast cabinet.

DITTO!

Aluminum scars too readily, heck Marine Clean (one of the prep steps for POR) will readily etch aluminum and render a prior polish unsatisfactory, and that's just a degreasing soap.

Then again, it is really rare to find aluminum so badly corroded that it needs blasting, and if you DO find it, it's usually too far gone to try to salvage.

FWIW

E

[Zs-ondabrain]

hold on, I think ya missunderstand what I'm getting at. When I glass bead the S.U.'s, ballance tubes, intakes and other aluminum, I do that for that "Cast Aluminum" look. Which is the look they usually have when new.

I would never bead or shell blast any Aluminum part that would be later polished. Below are some examples of the SU parts that got bead blasted for the final "cast Look"

pic #1 is of my current triple Webers and Cannon Manifold after I glass beaded them before rebuilding them and installing them on the Z

pic #2 is a close up of the SU's I sold a while back

Pic #3 is the complete SU set-up that I sold a few months ago.