Originally Posted by kevink
A 0.003" change in gap as the rollers turn is good. I bought a Barley Crusher that changed 0.008" as the drive roller turned. I returned it immediately, especially after the manufacturer said that it seems a little excessive and that I should just try it out. No thanks. I then bought a Mash Master mill. Out of the box there was about a 0.005" variance during operation. Because the rollers are geared, you can play with the clocking of the rollers to cancel out any variances due to out of round rollers. This is the second main reason I decided on this mill. On my first try at re clocking the rollers, I was able to get a variance of 0.002". I might be able to do better, but that is good enough for milling grain. The 0.008" of the Barley Crusher, though, was more than a step I might make when adjusting gap.
See now call me crazy but I never even bothered to measure my tolerances and gaps and such...I just tried it out testing it with grain.... and when I felt the crush could be a bit finer I loosened the lock nuts and adjusted it freehand on each side a tiny it at a time -each time checking it with grain, till I got the crush amount I wanted if the roler started to bind I readjusted while spinning it to make sure it was free.
Here we are 10 brews later and everything still works great....