Thank Martin, but did you see the dimensions of that stuff? It's all
in the 1/2" or larger range, which is fine for big industrial tumblers
tumbling large parts, but won't work for my applications. (This type
of ceramic media, btw, is what I come across on Ebay every so often.)

Eastwood doesn't give the dimensions of their plastic pyramid media,
but from the photos (with the nut and bolt surrounded by the media),
I'd estimate the largest dimension to be 1/4" or less.

We have a couple of Royson tumblers at work, and they just run and run.
They have a nice media selection listed on their website at
http://www.royson.com/index.html They have triangular plastic media
down to 3/8 x 3/8 x 1/4" and cone shaped plastic media down to 1/4 x
1/4". I think the minimum is 50 lbs, but send them an email for advice
and pricing.

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Regards,
Carl Ijames carl.ijames at verizon.net