Is anyone using an old stone grinder for their mash? I've got one that is 110 years old (french cut stone) and it is a bit variable in it's grind, but it's really cool to say I've used it. I worry that I'll end up with too much flour on my whole grain corn as well as my soft winter wheat..... Any insights would be greatly appreciated!
It's very cool that you'll grind your malt that way, Junas. How is the mill powered?
Grinding corn and wheat too finely can lead to some minor issues like foaming. But you'll be able to get around that rather quickly (i.e., adjust the gap between the stones).
What you want to watch is grinding it too coarsely. You can really lose out on yield, and have all kinds of problems in your fermentation. Mechanical rupture of the cell walls of those grains is necessary to expose the starchy centers to enzyme attack. Boiling is certainly a mechanical action on your corn, but it's not enough if you don't grind that corn to a reasonable size.
Do you have access to sifters to check your grind?
Hi Junas, this reply is a bit late but hope you still find it.
In Tasmania Australia there is a malt whisky distillery that produces its barley grist with water powered french millstones.
To alter the grist size you obviously alter the gap, but also the rate if grain feed is also important, especially if the top stone is not very heavy. Faster input gives coarser grist.
I restored the old milling machinery for this distillery.
I am also using old French millstones for my new rye distillery. In this case the stones are driven with an electric motor.