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View Full Version : Ceramic polishing media and corn cob?



Coug91
05-21-2013, 11:24 PM
I bought some ceramic media, sized 1/8" x 11/32", only to find that 5 of pieces fit snugly within the circumference of a 223/556 and 300BLK case. I ran one small batch and ended up spending more time with a sprinkler flag (wire) pushing the media back out of the case, so I sold it. I ended up going with the 2mm ceramic spheres. Throw the brass in the tumbler; add media, Dawn and LemiShine; cover with hot water. In an hour the brass shines like nobody's business inside and out. Only one small problem: The 2mm spheres are just the right size to wedge in the flash hole. They pop right back out when I run the brass through the press to resize or form it, but I don;t really like the idea of losing media in each case processed.

The abrasive dealer said their wholesaler told them that the 2mm ceramic added to corn cob is the cat's meow in brass polishing. Dry. I couldn't see how you would separate the ceramic from the corn cob when the corn cob is expended.

I'm happy with the job the ceramic spheres are doing on my brass, but I'm wondering if anyone has tried the ceramic/corn cob mixture.

Mpape
05-26-2013, 10:47 PM
Where did you get the 2mm ceramic spheres?

dbosman
05-26-2013, 10:57 PM
A bird seed cleaner type device using a vacuum cleaner to suck out the corn cob, might work.

Coug91
05-26-2013, 11:19 PM
Where did you get the 2mm ceramic spheres?

I bought it from a local abrasives dealer - Abrasives Spokane. They got it from a wholesaler in CA(?). They ordered 55lbs and I took half, so may still have the other 27.5lbs.

The stuff, with a bit of Dawn and Lemishine does a nice job on brass. I just finished processing about 10k pieces of 556 to 300BLK and as I was swaging primer pockets, set aside some of the nastiest pieces and put them in a separate woven nylon cinch sack. I was going to take pic before I put it in the polisher this morning, but forgot until I went out in the garage to check on the progress. The nasty stuff came out looking as good as the rest. I'm impressed... it's just the media getting stuck in the flash holes and primer pockets. Yeah, it pops out when I run it through the sizing dies, but I'm losing 1-4 pieces of media with each case. I picked up a good deal in a rock tumbler with 2 6lb Lortone buckets, so am leaning to switching to stainless pins. The ceramic spheres would be the bomb if they were 1mm so to fit through the flash hole.

Coug91
05-26-2013, 11:21 PM
A bird seed cleaner type device using a vacuum cleaner to suck out the corn cob, might work.

That might work, IIRC the ceramic media has a bulk density of 95lbs/cuft. Not sure what bird seed's bulk density would be, but I can't imagine it being heavier than that.