abrasive media question

the post about tumbling media reminded me of this question that I have been meaning to post. I have a customer who has a spin polisher that uses corncob media with an abrasive impregnated into it. Problem is that the media wears out at a very fast rate and is supposed to be replaced so frequently that the cost per part is out of line. He has messed around with making his own media but hasen't gotten far. Does anyone have specific info as to the ingrediants and techniques for doing this? Thanks. I think he said the specified media costs about $1.30 per pound, plain cob is like 20 cents if I understood him correctly. Abrasive has got to be pretty cheap per pound of finished media since it would be a small portion.

nuttin?

John-

I used to own a feed mill, though i never operated it. My best guess at an experimental process would be to get some small local mill to run a batch of corncobs through the hammermill. Give them an idea of what you want the finished size to look like so they can put the right screens in. Then run a ton or so, and experiment from there. It can't cost that much for a ton of processed corn cobs?

Then experiment with say glass beads vs maybe SiC mixed in by hand in small quantities '
til he gets the desired finish.

If nothing else this will give yo a bump.

smt

thanks, SMT, what haven't you done? feed mill , pilot, wood wacker,?

Dunno if it would work with the spin polisher and corncob, but on a vibe running walnut shells I've whacked up part of a bar of rouge on a cheese grater and tossed that into the mix to see what happened. It seemed to work just as well as the shells with pre-applied rouge.

About 15 years ago I was getting 1/4" cubes of maple and some abrasive paste from a distributer in New England. I will look through my stuff tonight and see if I can find a contact. I recall getting a small trash bag full of cubes and about a pint of 3 different grades of abrasive for under $50.
This combination was much better than anything else I ever used for removing small burrs and polishing in a tumbler. I used it on metal and plastic with excellent results.
I also recall hearing about using pecan shells with abrasive, although I never used it personally.