Grain Mill Roller Size

[KUB]

Just for the fun of it I’m going to build my own grain mill and I have a full fab and machine shop at my disposal. I’ve done a bit of research on roller size which always seems to suggest that the larger the roller the better because they tear the grain less than smaller rollers. Also at some point the larger rollers don’t need to be knurled to pull the grain through. However I have not found any definitive size for rollers where these 2 things happen. So does anyone happen to know what size rollers will crush instead of tear and also pull the grain through without begin knurled?

 

[Bilsch]

Biggest hobby mill is 2" I believe and a lot of commercial mills have 4" rolls with multiple stages. Also husk tearing has a lot to do with speed of the rollers and the difference in speed between the two opposing rollers. If you have the shop.. why not go hog wild and build a 3 stage, 4" stainless rollers with gear drive.

 

[day_trippr]

Here's an inspirational thread.
Check out the rollers on that bad boy

Cheers!