Gig,
You dont really "grind" them,it just spins them to blend the various mediums together. You have to be careful with some materials though,some of the synthetics will knot together if not cut up small enough.same with yarns.You need to cut up all the material in appr. 1/2 inch pieces before blending. furs are usually ok,they are short enough as is.some fur,like arctic fox is real long,and needs to be trimmed.
I havent tried the wet blending yet,seemed to be alot of work just to mix furs together,but like mentioned above,the matted fur after drying would be easier to work with. thanks for the advice! CJ