Polishing in a Cement Mixer?

PG-Zac · Post by **PG-Zac** » Tue Apr 20, 2010 10:04 am

I bought a new cement mixer today, and I'm thinking of using it for polishing aluminium parts. I've seen semi-precious stones tumbled in sand to produce a high gloss finish, and am wondering if I can do the same for my Goldie's parts.

Does anyone have any reason to NOT do this?
Has anyone here done this before?

Thoughts & comments please.
Cheers.

dusty · Post by **dusty** » Tue Apr 20, 2010 10:08 am

PG-Zac wrote:I bought a new cement mixer today, and I'm thinking of using it for polishing aluminium parts. I've seen semi-precious stones tumbled in sand to produce a high gloss finish, and am wondering if I can do the same for my Goldie's parts.

Does anyone have any reason to NOT do this?
Has anyone here done this before?

Thoughts & comments please.
Cheers.

I HAVE DOUBTS!

heathicus · Post by **heathicus** » Tue Apr 20, 2010 10:16 am

I had a rock tumbler when I was a kid and had dreams of becoming wealthy by making stylish jewelry from common rocks. But I digress.

I would love to see this tried, but like Dusty, I have doubts. But for the sake of satisfying curiosity, I hope you give it a shot!

mikelst · Post by **mikelst** » Tue Apr 20, 2010 11:02 am

I am just guessing but you would probably need to use a 'soft' abrasive or you could 'grind' your aluminum away in a hurry.

mickyd · Post by **mickyd** » Tue Apr 20, 2010 11:05 am

My guess is that the metal fins in the mixer will ding the aluminum. Assuming you were to find a way to protect against the fins, it would take a week or two running 24/7 to work.

Cylindrical tumblers with an aggregate media can be used to polish metal. They are VERY slow as compared to the vibratory type tumblers. For the amount of electricity you'll use to power the cement mixer for 150 to 300 hours, you could buy a small vibratory tumbler and knock it out in a day or so.

Heath and I both did ours with hand held vibratory sanders through a progression of grits followed up by buffing wheels and polishing compound.

JPG · Post by **JPG** » Tue Apr 20, 2010 11:36 am

dusty wrote:I HAVE DOUBTS!

Yes indeedy!!!!

tom_k/mo · Post by **tom_k/mo** » Tue Apr 20, 2010 1:13 pm

I also would have serious concerns about using either a Cement Mixer or a Mortar Mixer (there IS a difference) to polish parts. Too much chance to damage the parts and it seems as if it would take a lot longer than a vibratory polisher, or a Soda Blaster, or media blaster using glass beads, or walnut husks.

On another note, I have a good friend that used a mortar mixer very successfully for removing the outer husks from Walnuts he harvested. He just dumped them in the mortar mixer, added some water and let it go for an hour.

heathicus · Post by **heathicus** » Tue Apr 20, 2010 2:59 pm

Don't listen to them! Go for it! And take pictures!!

JPG · Post by **JPG** » Tue Apr 20, 2010 4:30 pm

heathicus wrote:Don't listen to them! Go for it! And take pictures!!

If you need something to soften the impact of the parts against the vanes, throw a couple of those 'daily smiles' in with the parts!:D

anmius · Post by **anmius** » Tue Apr 20, 2010 4:32 pm

Having polished soft metal parts commercially, I would have very serious doubts about using a cement or mortar mixer. The fins would certainly impact the metal objects and d[font=&quot]efinitely[/font] leave marks. And soft metal (like aluminum) is not polished at all by abrasives. Small oval shaped stainless steel ball bearings works best. And you have to have a large "media" quantity to "parts" ratio just to make sure the parts don't bang together.

Get a small rock tumbler or the vibratory tumbler and small ss ball bearings.