Cleaning oxidized aluminum castings

[Karl Hamson]

Is there any way to clean the white powder off besides elbow grease?

[Walt G]

Are the castings in place on something, removed, how large? they could be the size of a baseball or the size of an oil pan, more information as to what has to be cleaned and if so will the surface then be polished ? Does the object have a lot of small areas that are hard to get into or are they flat or curved areas large enough to easily work on?

[edinmass]

Mothers polish and a Dremel..........care must be used.........and take your time. Don’t ask how I know.

[Karl Hamson]

Crankcase for a 29 Hudson.  Large and on the bench.

[edinmass]

Vapor hone........clean it with steam first. Will look like new. 

[Bush Mechanic]

I blasted mine with fine glass beads, at low air pressure, (around 50 psi), then hand rubbed the finish with scotch-brite. They cleaned up very nicely, and the scotch-brite removes the flat look. The very fine swirls in the finish may not be for everyone . It looks good to me, but I'm not into showing the cars. Maybe try different methods on a scrap casting.

[61polara]

WD-40 does a good job as well.  

 

[edinmass]

Watch this video........

 

 

[vintchry]

Wow, I like that!!!!!!!

[TAKerry]

Vapor honing looks pretty sweet but expensive!  I saw a blip on the hemmings website where a guy built a homemade sonic washer. Looked pretty simple and has me intrigued. He attached a 1/4 sheet sander to a tub filled with CLR/water. Put the parts in the solution and let it vibrate for a couple of hours. They came out looking brand new. He also made a tumbler the same way, same results.

[edinmass]

I started using it when my neighbor bought one......It's my go to way to deal with most parts today. First a hot water based safety kleen unit, then the vapor hone. It is easier on the parts than sand or glass...........and the cabinet is easy to see......the window doesn't get ruined like sand or glass......and NO DUST in the shop........you can place the unit in a machine shop or engine building area with no down side. 

[TAKerry]

Ed, can you use it on rusty steel parts as well, like one would use a media blast cabinet?

[edinmass]

Yes......it's a bit slower. For post war stuff where parts availability is unlimited sand blasting is still best.(faster) Vapor hone is a slower process.......better control, and sometimes it will not get everything 100 percent. It won't ruin anything, and thats 99 percent of the game in pre war. On aluminum its fantastic. Motorcycle stuff it's a must. It's great for small hardware. I use it on all the engine accessories.....carburetors, water pumps, distributors..............I like it a lot.

 

The unit I use is just like a regular blast cabinet......a foot trigger and a nozzle .............the unit in the video is more for large production shops.....works the same. 

Edited December 20, 2020 by edinmass (see edit history)

[TAKerry]

Thanks.

[bryankazmer]

The cleaner using a sander is not an ultrasonic cleaner.  The sander is stirring a part in a solvent bath, it's most like a part washer.  An ultrasonic cleaner operates at about 40,000 Hz.

Vapor honing has been used in the tooling industry for a long time - it is as effective as described.

[edinmass]

I agree with the above. Only new thing is they are available for small shops and home use now.......but still not cheap yet..........I expect in a few years the numbers will cut in half on the vapor hone cabinets.

Edited December 20, 2020 by edinmass (see edit history)

[joe_padavano]

I had surprisingly good results cleaning a corroded aluminum transmission case with my soda blaster. This particular part had sat outdoors for years and had mud and corrosion, and I figured I had nothing to lose. Cleaned up amazingly well.

[lump]

15 hours ago, edinmass said:

Vapor hone........clean it with steam first. Will look like new. 

Holy smokes, Ed. I had never heard of this. Looks fantastic. I wonder how it would work for cast aluminum intake manifolds and aluminum alternators of the muscle car era. Restorers tend to dislike these items when they have been glass bead blasted. Some folks use walnut shells, and claim better results. But the goal is to make these rough-cast-unpolished aluminum components look like they did when new, and it is a real art to achieve that appearance by blasting. Maybe vapor honing might be a viable alternative. 

[joe_padavano]

3 hours ago, lump said:

I wonder how it would work for cast aluminum intake manifolds and aluminum alternators of the muscle car era.

 

That's exactly what it gets used for.

[John348]

On 12/20/2020 at 2:09 AM, Bush Mechanic said:

I blasted mine with fine glass beads, at low air pressure, (around 50 psi), then hand rubbed the finish with scotch-brite. They cleaned up very nicely, and the scotch-brite removes the flat look. The very fine swirls in the finish may not be for everyone . It looks good to me, but I'm not into showing the cars. Maybe try different methods on a scrap casting.

 

I have used the plastic media on aluminum manifolds as well as alternators housing and it worked well, not overly aggressive, but is a slow process.

Edited December 21, 2020 by John348 (see edit history)

[Bush Mechanic]

9 hours ago, John348 said:

 

I have used the plastic media on aluminum manifolds as well as alternators housing and it worked well, not overly aggressive, but is a slow process.

 

John, is that granulated plastic ? It sounds like something I need. I looked for walnut shell, but that is not available here in Tasmania, and quite expensive shipped from the mainland. Ed's vapor blast looks like a good thing, if it becomes available at hobby price level.

[John348]

4 hours ago, Bush Mechanic said:

 

John, is that granulated plastic ? It sounds like something I need. I looked for walnut shell, but that is not available here in Tasmania, and quite expensive shipped from the mainland. Ed's vapor blast looks like a good thing, if it becomes available at hobby price level.

 Yes it is, I will look for the exact information of the product tomorrow

[bryankazmer]

there are multiple types of plastic blasting media.  I'm not familiar with choosing the correct type for a given job, but check before buying.  By analogy, talcum powder and carborundum grit are both mineral media, but perform very differently.