Bownarra's right on them generating a lot of heat & dust but one trick I have found to minimize it, is I make these sleds out of bamboo flooring one for my band saw and one for grinding it really minimizes grind time and stretches out material ,I have a venerre blade for my band saw that preety much cuts the tapper so grinding just takes out the saw marks , guys that I know with home brew grinders complain about hand feeding & debits in the lams the conveyer system eliminats it , some of those guys have been using trued out granite slabs for the feed table , larger drums work better as far as ware on the sand paper !