What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

What Media Blast Material??

S

SkookumFlyer

Member
I'm putting together a media blasting cabinet and wondering if anyone has advise for material safe for aircraft parts.

Any recommendation would be appreciated.

Thanks,
 
Media selection is going to change, depending on what you are trying to do and the pressures you run in your cabinet.

I use glass beads for all steel and aluminum forgings and castings. I don't blast sheet aluminum parts at all, due to the possibility of stretching the sheet . For al angles and extrusions, it's either glass beads or walnut shells.

For pressures, I run as low as 40 psig and as high as 90 psig.
 
Sodium bicarbonate is a gentle blast medium that can be used on aluminium sheet in the thicknesses we mostly work with. It uses lower pressure than most other media, and the particles disintegrate on impact.
 
dmn056 said:
Sodium bicarbonate is a gentle blast medium that can be used on aluminium sheet in the thicknesses we mostly work with. It uses lower pressure than most other media, and the particles disintegrate on impact.
Click to expand...

I have used soda successfully on thin alum sheet. It will easilly remove paint and does etch the the surface, but do not believe it is removing any material like more agressive media would. For the cabinet, spruce sells three grades of composite blasting media that is safe for all alum and also doesn't remove material. Should be more effective than walnut shells and won't remove material like glass can.
 
Last edited:
+1 on the sodium bicarbonate blast for paint removal it works very well and can be cleaned up easily with water though if you are going to use it on thin material you should test it on scrap material of the same thickness it is gentler than the other methods but it can dent thin metal if you get the pressure too high.

We also use plastic media though it can be difficult to clean the media after a while. It probably wouldn't be an issue if you are going to use it occasionally you can just swap media but if you are using it a lot it can be a problem. The same goes for glass media after a while the glass beads break up and they become less effective. Aluminum oxide is very effective, but it is also very aggressive and can remove a lot of base material if you Aren't really careful.

A piece of advice from my job at Tinker AFB. I used to work turbine engines and there are two things you should never use glass bead blast media on.

Titanium and any part with internal oil passageways.

Tiny shards of the glass can imbed into the titanium and cause problems.

On parts with internal oil passageways any media you get in the passageways and do not get out will clog oil jets and other small passageways when mixed with the oil. We crashed an F-16 because of this a few years back. They are supposed to mask the passageways, but we did some testing and found that some glass beads will make it around the masking no matter what we did.

Also if you are blasting anything with chromated paint wear a respirator (not just a dust mask) when disposing of the media as you do not want to breath in the residue that stuff can cause cancer. They have the guys in the USAF that work with that stuff get periodic blood test to make sure they aren't getting any in there system. We are moving away from chromated paints/primers as dealing with the hazmat issues on both application and removal just isn't worth the cost even though it is still the best corrosion preventative.
 
What about the suggestion of never using the same batch of media for both Steel and Aluminum.

Following the opinion of a man I trust, I have bead 3 cabinets, steel only, aluminum only and "Junk/everything else"
 
Yep forgot about that one. you will get a bit of aluminum or steel mixed in with the media. If you blast an aluminum part with media that has been contaminated with steel the steel particles can imbed themselves into the aluminum and cause corrosion.
 
You must log in or register to reply here.
Back
Top