Another great post! I did a quick search on "ground walnut shell" and came up with a supplier. (I have a need in the near future and will do more reasearch and post if I find better) http://www.abrasivedepot.com/ad/mss/mss-pc.nsf/WebEngine?OpenAgent&cmd=category&category=JSTD-5WNSXM Considering a 30oz WS shaker is $9.00 (give or take) that comes out to $4.80 per pound. So even with UPS shipping you can save quite a bit, at least on the larger sizes. I do have a question, anyone have any idea of what the N gauge equivalent of a 20/30 grit size would be?? Thanks in advance.