Blasting Aluminum

[jdeoliveira74]

I have recently aquired a M274A5 mule.
It needs to be stripped of paint to bare aluminum.
What are my best solutions for doing this?
I have used sandblast in the past on steel but knw it is very agressive on aluminum.
Should I be looking at soda blast or is sandblast OK with the correct sized media?
I know some guys use glass bead on aluminum as well but for an entire mule this is not feasible.

I think walnut shells for blasting too I have seen it used on fiberglass

 

[peecook]

I took a pressure washer (4000 psi) with a 0 degree angle tip and took the majority of paint off of my m109 box. it worked really well and there were at least 3 layers of paint on it.

 

[derby]

I have used the Aircraft Stripper in steel and it works great. Aluminum I don't know. It is some nasty stuff, You will need one of those Nuke suits to work with it
I have read on another site that deals with Mercedes that there is some sort of clay prep needed for surface prep on Aluminum hoods and trunk lids.
I would like to see the results of what ever you end up using. Lots of pix please!

 

[JCKnife]

I would like to see the results of what ever you end up using. Lots of pix please!

As requested. The first pic is still not quite done, but very close. Pics 2-4 show a process. The last pic is after 2 sessions of stripper and thoroughly rinsed.

 

[sigo]

I just stripped and repainted an aluminum mermite. It took 3 applications of the "aircraft stripper" stuff to get the paint off and even that didn't get it all. After much scrubbing with a green scratch pad I got about 95%, but getting it all out of the seams and edges was **** near impossible. Some light sanding got it smoothed out enough to make the finish decent. I happened to notice the can of "Aircraft Stripper" had a prominent notice... "Not for Use on Aircraft" Funny.

I've got a S788 shelter i'd like to refinish next. Seems like walnut media would work best, but any tips for stripping an aluminum shelter would be appreciated. There is not way I'd use chemical stripper for a project as big as a shelter.

 

[JCKnife]

Update: here is a pic of primed parts after wet-sanding with #400 sandpaper. Used Duplicolor self-etching primer.

 

[derby]

They look new!

 

[tcody]

I have another vote for soda. I used it for brick restoration and it is very nice for delicate stuff. However, even soda will bend thin sheet and leave distortion, pitting if you are not careful. Nice thing about soda is it is not toxic although you still have to have proper safety equipment. You can blast wet or dry. It is pretty messy like pretty much all the other options. If you have a complete vehicle wet blasting will keep the dust down. If you dry blast in a closed environment please don't have any open flames close. The dust can ignite like a grain bin.

 

[JCKnife]

Quick update I've got a lot of time in these winches but they are starting to get towards re-assembly. Here's the latest, one of my break boxes is primed. Masking the data tag turned out really well. Of course the lid is steel not aluminum but it seems to have taken the primer well.

 

[C15TA]

Wilfred, (Captw1) tool his Mule bed to my buddy who is a sandblaster and he did a great job. He did it holding the nozzle back a bit and used fine sand, Wilf was happy. His Mule is not a pristine restoration but a daily driver around his property and for Sussex, Gilbert and Coe Hill. His theory is to make it look great but be able to use it. We dismounted his tires this week so he can get the wheels blasted. One of the tires had a 16" tube.
Cheers,
Barry

 

[Beerslayer]

I've got a 5 ton winch to do soon. It is pretty rough looking with multiple coats of paint and gunk. I was planning to water blast it with 4000 PSI of water and some fine sandblasting grit.

Will this really tear up the aluminum or just roughen it up a bit? Seems like with heavy cast parts it shouldn't hurt much.

Comments appreciated.

 

[SouthernSteel]

im not sure howthick the mule aluminum is but i used to blast the meps and the water buffalo tanks and the ac units which are aluminum we used garnet at about 80 psi i never had a problem i never warped a door on a mep and those were thin i also used glass bead the glass bead was the least evasive how ever it left the surface on the aluminum surface kinda shiny hope this is some good info and i hope i could help i was a blaster for 5 years doing military equipment and i was a blaster in the civi world doin parts for about 5 years for a combined 10 years so if i can help yall out let me know i will gladly answer any questions

 

[sandman7655]

i use a water blaster at 4000psi and fine abrasive.it gives the aluminum an etched finish ready for paint.

 

[connectingbar]

I sandblast a ton of boatmotors for restoration. The best way is to sandblast it with wallnut media then spraying it with a self etching primer. I usally spray a filler to fill in the pits left by the blasting and corrosion. Then add the top color.

This way it will take the abuse of the outdoor environment without any ill effects.

I have a few 1952 3hp evinrides that I have done 20 years ago that look as good as the day I painted them. And that is under extreme use while duck hunting

 

[ssdvc]

What can I use on some two piece aluminum wheels? I want to take down the barrels, clean them up real good and polish the lips and paint the inside of the barrels. The faces are fine. Is Black Beauty or Black Diamond a good choice? I also saw some glass beads at the Tractor Supply near me.

 

[Jeepsinker]

I use only glass bead on aluminum. On steel I use garnet.

 

[Ray70]

SSDVC, Black beauty and Black Diamond are both coal slag products, great for blasting steel, but I'd say way too aggressive for aluminum. Also, be careful with both of them, they tend to have short "string like" pieces mixed in that easily clog your nozzle. Always sift it first. I would only use the fine size, not medium unless you have a big sandblaster with 1/4" or larger nozzle. For doing aluminum I'd say wallnut, glass bead, plastic bead or soda blast. Also remember to clean thuroughly if soda blasting, it leaves a residue that must be removed before priming. Then use a 2K epoxy primer or seft etching primer for best adhesion to the aluminum.
Blasting will work much better than chemical strippers. If you blast the areas you want to polish, sand it afterwards and get progressively finer until at 600 grit, then begin polishing after that.

 

[RickWG]

Other options are blasting it with plastic media. There are different types & grits so you'd want to look into that. (melamine seems to be the hardest, polyester is much softer) Dry Ice blasting works great on aluminum. The latest & greatest is laser paint removal.. but that's probably a bit spendy.

To make aircraft stripper work better for multiple layers of paint: coat the part & then wrap it in aluminum foil to stop it drying out.
Restaurant supply shops with sell stuff called Carbon-Off in aerosol cans. It's designed to remove baked on clag from pots & pans etc & is safe on aluminum. It just happens to smell EXACTLY like paint stripper & oddly enough removes paint in rapid fashion. Also handy for removing carbon from exhaust & engine parts. Leaves pistons looking brand new (but regular paint stripper also does that too)

 

[iatractor]

If you don't mind using a 4-1/2 inch angle grinder, there are some products out that do a pretty good job of stripping paint without damaging the material underneath. Norton abrasives makes a wheel called a ber-tex rapid strip. Very similar to what a 3M Scotch-Brite pad will do, but this is a bit more open and fits on the grinder without special pads. Works great at destroying paint and leaving a near ready surface. Airgas is an authorized distributor, in fact many stores now carry this product in their Radnor store brand (made by Norton). I use these all the time. Norton also offers a rapid-blend wheel of similar style that puts the final touch on the material.

 

[RickWG]

Here's a video of the laser cleaning/stripping in action:

http://www.wimp.com/powercleaning/