We are folloiwng protocol by Hansen et al. (2015) Sci. Pharm. They recommend a Rancilio coffee grinder but these are several hundred dollars. Hoping to use something a little less expensive.
Consider a regular coffee or spice grinder. Stop by Avalon Mall and ask in the kitchen section of Sears. Starbucks Coffee sometimes sells them in their stores too.
It really depends on the required particle size. I have done some testing on prcessed and dried collagen and could get decent results with a basic blender to make smoothies. Particle size was around 0.5-5mm. I then continued with a Burr grinder to go towards 90%