Great work on this mod I have a suggestion put in an upgrade path for the water wheels.

To explain a little better you would make your first lot of water wheels with the stone shaft, later on when you have some basic resources you can make a iron rod and combine it with the water wheel to replace the stone rod so a tier system could be used

Tier 1 : Stone rod
Tier 2 : Iron rod
Tier 3 : Gold rod
Tier 4 : Redstone coated Iron rod
Tier 5 : Redstone coated Gold rod

The old rod would remain in the crafting grid for reuse on the next upgrade

Also how the work going along for the grinders and auto hammers going ?