Blasting media question?

[Ed]

There are different types of blasting media out there. I was wondering if a specific type is better for a particular application. Or certain surfaces.

So far I've encountered:

Sand

Glass Bead

Aluminium Oxide

Walnut shell

Any others?

[2ManyZs]

2 others....

Silicon Carbide, which is a one of the harshest cutting abrasives, used for glass etching.

Poly or plastic media, which is good for cleaning softer metals such as aluminum and brass.

Eastwoods has a nice little chart that shows the types of projects you might need to use the abrasives on, and which ones are good, better and best for each as well as the recommended pressures for each.

Don't know if it is on their webs-site or not, if not, I'll try to scan it so you can get an idea of which media is good for what.

[2ManyZs]

Here's the chart. I couldn't find it on their web-site so I scanned it out of their newest catalog.

[LanceM]

From my limited experiance:

Sand - available in different grades, vary abrasive, siclica(?) sand is dangerous to use can cause lung problems, the others are probably not much better for you. Wear proper respertory protection. Sand can be reused but the sharp edges brake off making it less effective. Must be very dry or will clog, probably the cheapest media to use.

Glass Bead - is more reuseable than sand as more sharp edges are formed with use but it becomes finer with each use (breaks up), less abrasive, often used for cleaning parts, less for rust removal, dangerous see above.

Aluminium Oxide - no experiance but I would belive it to be as agressive as sand and more reuseable but also more expencive.

Walnut shell - More of a polishing/cleaning media, non agressive, must be sifted before use for uniform size to prevent clogging. Typically used on non ferric metals.

[Ed]

Thanks Guys.

[2ManyZs]

I've been using the aluminum oxide in my blasting cabinet for years and like the results. It does a good job on all but the toughest rust, just have to take your time and sometimes go over it twice with the worst stuff. I've used about 100lbs in the last 4 or 5 years, it does turn to dust after a while, but it holds up pretty good considering the use it got when I was sandblasting every piece of the suspension off my car.

I've also used glass bead on aluminum with good results as well.

Note, this is in a cabinet where you don't lose any media.

For a blaster outside or where it's going to be diffuicult to recover and re-use the media, plain old play sand is the way to go. Cheap, and does a decent job, all you have to do it make sure it is dry before you use it.

[Ed]

I got the play sand for outside jobs and have been pretty pleased with the results. I'm building a blasting cabinet out of an old freezer and was wondering if I used the sand there on aluminium what would happen. I'm gonna get some glass beads for the cabinet.

[LanceM]

My experiance with sand on aluminum is that it gives it a frosted look, from what I've seen from items that I had glass beaded they just look clean not frosted. I for sure wouldn't use sand say on the combustion chambers of a head.

The more I think about it I wouldn't use sand on aluminum unless I was going to paint it and really wanted something for the paint to grab on to.

[1GENZED]

I have used the silica type of abrasive at school in Autobody/restoration class it works pretty good for surface rust,

but any scaling, and it just takes to long.

The Blaster I used was a portable recycling type. The gun had a

vacuum attachment with a brush bristle seal that would seal around the gun/material and suck the sprayed abrasive back into the guns filtered hopper.

I was very impressed with its versatility.

You have to be very careful with the silica as it is harmful. In some areas it is actually classed as a "controlled substance".

You can only buy it here in Toronto if you have a licence

(or if you know a bodyshop:).

Ahmed

BTW does the playsand still give you the dust cloud

I would think that because of its large grain size it would mist less.

[Zvoiture]

Yes, I too feel the blasted media is horribly biased towards the left.

steve77

[LanceM]

Steve Steve, Blasting not blasted, but I agree with your statement

[ZwolleY]

UHHHHHHHHHHHHHHHHHHHHHHHHHH. Watch it Hunt, don't get involved in the media question. Almost too big an opening to pass by though.