Mill concept

[mattd2]

Hahahahahaha.... I was actually just thinking about my mill problems. Really 2" is still not big enough for smooth-ish rollers to grip the grain and get the second roller spinning by itself. I have the mill apart and was going to drop the rollers of at the shop to see if the can either put more knurl on it (they only have a bump knurler so maybe not ) or rought them up a bit (sandblast maybe to get a P120 - 150 sandpaper like finish).
It's been good for small amounts of grain, ~1kg-ish, but trying to go through enough for a 5-10 gallon batch the electrical tap would be ripped apart 2, 3, 4, ??? times.
Other updates are;
I used so Al. can to provide end plates to stop the grain falling out (worked good but I will make some more using a ruler
Got my dad's old "drill press" (removable drill with stand) which runs at 600 rpm, much better than trying to control the trigger on a 2750 rpm electric drill!

 

[mattd2]

Update!
Got the rollers back from the shop yesterday and put it together tonight. It is working awsome. Just ripped through 2# of grain (the hopper is a plastic 3 litre juice and holds just over 1 kg of grain).
Can't wait to do the inaugural milled malt brew! Got about 5# sitting ready to go, might mill a bit of crystal and do a mini BIAB tomorrow...

 

[Chuginator]

That's great news! Congratulations!

 

[kenc_zymurgy]

I'm curious if anyone has looked into using 6" or 8" bench grinder wheels as DIY mill rollers? With that big diameter, you should not have the problem of the idle wheels not turning. You could probably grind against a fixed plate?

It would seem to take more torque, but with the~ 4x higher speed at the outside of the wheel, you should only need ~ 1/4 the width on the rollers, so maybe the forces are bout the same?

Anyhow, I figure most DIY'ers have more access to grinding wheels and a frame and shafts, than to the machining needed for long 2" rollers.

Thoughts?

-kenc

 

[day_trippr]

For all that diameter, most bench grinder wheels are only an inch or so thick. I think it would be a major challenge to come up with a way to keep grain from finding their way to the sides and missing the whole "crushing" thing...

Cheers!

 

[camiller]

I'm curious if anyone has looked into using 6" or 8" bench grinder wheels as DIY mill rollers? With that big diameter, you should not have the problem of the idle wheels not turning. You could probably grind against a fixed plate?

It would seem to take more torque, but with the~ 4x higher speed at the outside of the wheel, you should only need ~ 1/4 the width on the rollers, so maybe the forces are bout the same?

Anyhow, I figure most DIY'ers have more access to grinding wheels and a frame and shafts, than to the machining needed for long 2" rollers.

Thoughts?

-kenc

After two-three years of use in a homebrew shop I had to replace the stainless steel rollers in a barley crusher because the knurling had worn down. I imagine that bench grinder wheels, which are most definitely not steel, would wear down rather quickly. IIRC Somebody on here did a mill with cast concrete rollers.

Edit: found it - https://www.homebrewtalk.com/f51/my-diy-low-budget-concrete-roller-grain-mill-119521/

 

[mattd2]

Used the mill again on Monday night (really got to start brewing more!) and it was giving me some problems. I think it all comes down to running it to fast with the 600rpm drill. It was not dragging the grain into the mill at startup. I got round the issue by "manually" starting the crush by turning the drill by hand (i.e. slowly) until I felt the grain being drawn into the rollers and then starting the drill up. Doing this it went through ~10# of malt no issue (I also conditioned the malt first). Just had to take a few stop-starts to refill the tiny hopper!
I think I am happy enough with it to build a propper hopper/base for it and maybe try and find a motor to run it at the correct speed (and hopefully this will cure my startup issues).

 

[mattd2]

...I got round the issue by "manually" starting the crush by turning the drill by hand (i.e. slowly) until I felt the grain being drawn into the rollers and then starting the drill up...

Another batch done last night. Mill went good, closed it up to about 0.041". Had to "manually" start it again but had the "clever" idea of stopping before the hopper ran empty to refill it, this way it started up fine on the next run with no issue. I think April will have to be the month the new hopper gets built.
Cheers all