Which Sandblasting media

[ShelbyCSXT]

So I'm looking at McMaster-Carr's catalog. I'm thinking that I'd like to get a bigger size media so that it lasts longer than smaller media. Does Aluminum Oxide break apart into smaller pieces or shatter completely? Should i get the 220 grit or is that too big? What size grit would you suggest?

Aluminum Oxide— 50-lb. Box
Mesh__Grit__Price
18-50__36__49.33
25-70__46__49.33
35-100__60__51.73
45-140__80__54.62
70-270__120__$54.62
80-325__150__54.62
100-400__180__58.17
120-450__220__59.13
N/A__280__98.08
N/A__320__113.46
N/A__400__125.00

I have a nice sized blasting cabinet, but have no idea what size the tip is or who the manufacturer is. Does anybody have any links for sandblasting guides/instructions relating to "tip/nozzle size for type of media used"?


Found this info on this site:
The aluminium oxides
These artificial abrasives are crystallized aluminium oxides obtained thanks to a fusion in an electric furnace. We obtain thus a product with controlled physical and chemical properties.
The fusion guarantees the quality regularity and the absolute absence of free silica.
There are two families used in the abrasives to be projected:

The brown aluminium oxide
It is a brown aluminium oxide obtained by fusion and reduction of a mix of selected bauxites and characterized by high titanium content. This high content increases the grains solidity and tenacity allowing higher work duration of the recycled grains.
- its apparent density ranges between 1.7 and 2.2. (real density: 3.96)
- its hardness is 9 on Mohs scale.
- its granulometry ranges between 0.1 and 2 mm (see chart granulometries)
- its using cycle varies from 8 to 20 (depending on calibres and uses).
The brown aluminium oxide is particularly adapted for stripping or the surfaces finishing through compressed air projection. (see compatibilities)
The high resistance of the grains to erosion and shocks, their solidity and their mordant, give them remarkable efficiency allowing the use of compressed air pressure very inferior to the ones required by other products. The advantages are undeniable:
- work speed increased,
- abrasive consumption reduced,
- compressed air consumption reduced,
- dust emission reduced,
- super pressure of the cleaning after the treatment,
- good roughness of the treated surfaces.

The white aluminium oxide
It is an aluminium oxide obtained by fusion of pure alumina. Its very low iron and soda content gives it a great abrasive power. It is a very high purity product subjected to numerous treatments aimed to give it a grains shape with equal axles. These sharp grains cut the surfaces simultaneously scraped and grazed by the fine elements. It is not an action only based on the jet power with the deformation fear.
The white aluminium oxide is used for stripping works or surface finishing through compressed air projection and particularly for the fine sheet metal or when a lesser pollution with iron is pursued. It is also used for tarnishing and glass or stone engraving as well as for the surfaces decorative finish.
- its apparent density ranges between 1.6 and 1.9 (real density: 3.94)
- its hardness is 9 on Mohs scale.
- its granulometry ranges between 3µ and 2.4mm (grains F8 to F1200 according the standard FEPA 42-F-1984)
- its using cycle ranges from 8 to 20 (depending on calibres and uses).
As the brown aluminium oxide, the white aluminium oxide is characterized by solid grains with sharp edges which have a great hardness and a great resistance.
The brown and white aluminium oxides are both recyclable.

[ShelbyCSXT]

Does anyone think that 220 grit is too big

[pickleboy]

i would get the 180 or the 220. when i blast rougher than that i usually knock it down with 180 paper just before i clean and powder.

[mtnbiker]

Someone posted that aluminium oxide is dusty.... I have found the opposite. It is the least dusty of everything I have tried.

I am using 80 grit aluminium oxide for everything I bead blast. Works great and get excellent adhesion. I am very impatient and want to spend as little time at the blaster as possible.

I also use carbide tips... they last much longer than the ceramic ones. They better for as much as they cost.

I also wanted to add that I shoot everything cold, or at least room temp. And I get real nice results.

By chance was your black beauty slightly wet? That will cause it to clog fast. Or if your water seperator in you compressor is not working good... it will let moisture in and start to clog the blaster.

And lastly... be careful on the mail order stuff. Be sure to check shipping prices. Locally it was much cheaper for me because of that.

[ShelbyCSXT]

Originally Posted by mtnbiker

I also use carbide tips... they last much longer than the ceramic ones. They better for as much as they cost.

And lastly... be careful on the mail order stuff. Be sure to check shipping prices. Locally it was much cheaper for me because of that.

I'll deffinitely look into carbide tips. McMaster Carr is local to me, so I can will call everything I just picked up two 80lb bags of black beauty for $30. Looks like im gonna do a little bit of blasting outside untill i buy some Alum Oxide.