Originally Posted by HorizontalMike

I also just yesterday, added some untreated walnut to my corn cob media (for a 50/50 blend). My brass/nickel-plate came out very clean and shiny, though EVERY boxer hole had media packed in it. The walnut I used is called Litter Maid that I picked up for cheap at WallyMart. Some of this Walnut is very fine/dusty, but my Thumler Tumbler UV10 has a tight lid that prohibits letting dust into the shop. Works like a champ. BTW, at end of tumbling I pour all of the media into a large dedicated metal salad bowl, and remove the brass with a spaghetti strainer.

NOTE: Quick cure for packed boxer holes... By returning brass to empty tumbler and running for 15-30sec. this knocked ALL remaining media from the boxer holes.

Not sure about using Nu-Finish to "control" dust. I prefer in slowly returning media from dedicated salad bowl to tumbler, AND THEN stopping the very last dregs from returning to tumbler. At the bottom of said bowl is where most of the finest dust collects, so tossing this small amount after each tumbling run makes sense to me. And just maybe, my media may eventually be free of the fine dust after repeating the process above.