We find good results if we set the chaffer about 3/4" open, and the sieve roughly the same (you can fine tune it after), slow the cylinder speed as slow as you can go (to prevent mechanical damage to the peas) and open your fan up quite high can give you a nice, clean sample. We set our fan at setting 4 or 5 on a R75. Also set your concave (front and back) around 3/4" clearance. That you should give you a reasonable place to start. Hope this helps.