What RPM do you run your grain mill at?

[Catt22]

I will replace the loose wires with a 4 wire cable & plug in connection, but this was a do it without going to the store kind of day. Also helps explains some randomness like copper solder couplings! There is groove that the bucket lid fits on. Fwd-Off-Rev switch.

I'm curious as to what prevents grain from spilling off the rollers as it feeds from the hopper. I've always thought that it would be better to mount the mill below the platform rather than on top of it for this reason.

 

[Misplaced_Canuck]

How do you get 500 ft-lbs from 40 in-lbs? in-lbs to ft-lb is divided by 12, not multiplied...

M_C

Yikes. I would think that 40 in-lb. would have been plenty. Thats almost 500 ft-lbs. We'll see, I've got all the parts. I've got the 2" rollers.

 

[bbognerks]

How do you get 500 ft-lbs from 40 in-lbs? in-lbs to ft-lb is divided by 12, not multiplied...

M_C

You are a little late to the party. I pointed this out in post #37

 

[Misplaced_Canuck]

Didn't see it. Usually I arrive early and leave late.

M_C

You are a little late to the party. I pointed this out in post #37

 

[RDWHAHB]

I'm curious as to what prevents grain from spilling off the rollers as it feeds from the hopper. I've always thought that it would be better to mount the mill below the platform rather than on top of it for this reason.

Cell phone pic glosses ove some details. There is a small piece of plexiglass that coveres the top of the rollers. Under mount would work great too. I decided on mounting above so that I could sit on any bucket w/o modifications. I'm trying to avoid having a big cabinet style crusher.

 

[shushikiary]

On the chain comment...

Sense all my grain is conditioned before use I get next to no flower, and the motor is above the dump so very little flour dust gets up there even if I dont condition, so I dont think that will be a problem for chain wear, if it starts to I'll just clean the chain if I have to with my bike chain cleaner.

Sadly I already ordered the sprockets and they just got in today so I already have 18:36, so we'll see how that goes, if it does wear like you're worried about I'll keep what you said in mind and go to 18:37 or 39.

I dont know expensive the belt drives are, but I like that the sprockets, chain, and shipping only cost me 25 bucks.

Also, I have the 1.5" rollers and not the 2" rollers, I suppose I should have made that clearer instead of just saying "regular size".

I'll get it hooked up tonight, I might just buy some grain on my way hope to mill and see how it comes out, it's so cheap, haha.

 

[BrewBeemer]

On the chain solvent or paint thinner clean it then apply White lightning's Clean Ride wax based chain lube, a hell of a lot cleaner than that factory oiled chain.
Far as a load test run a cup of dry corn thru it, rather nasty to crush.

 

[shushikiary]

Well, tested the mill.... 90 inch pounds still isnt enough. It was close though. I could dump about 2 coups in at a time and it would survive, but if I filled the hopper it would bind.

I'm going to have to get a higher torque motor and then use the same gearing to double the torque again, haha.

 

[BrewBeemer]

What would be intresting if you filled the hopper then used a in/lb torque wrench to get the starting torque as well a rotating torque readings.
With the three roller mill 2" diameter rollers geared up 3.77 times the 1/3 hp worm drive unit i'm looking at 149.77 in/lbs. This at rated torque rating of the precision Gear worm drive. The manufacture told me it will handle 125% of the gearbox rating without harm as long as the motor amperage is within rated specs.
This will generate 187 in/lbs (15.60 ft/lbs) at 110 rpm's to the 2" diameter three roller mill.

 

[Catt22]

Well, tested the mill.... 90 inch pounds still isnt enough. It was close though. I could dump about 2 coups in at a time and it would survive, but if I filled the hopper it would bind.

I'm going to have to get a higher torque motor and then use the same gearing to double the torque again, haha.

There may be an alternative solution to your problem. It has to do with the rate that the hopper feeds the grain to the rollers. You can lighten the load on the mill by restricting the feed rate. IOW, if the grain is not permitted to spread across the entire width of the rollers, the required torque will be less. The JSP Maltmill uses a restricted feed for just this reason. IIRC, the JSP rollers are about 10" long. This would seem to be an advantage at first glance, but the reality is that if you load up the full width of the rollers it would require one hell of a lot of torque to turn them. So, my suggestion would be to choke down the feed rate somehow. If I were doing it, I would build it so that the feed rate was adjustable. That way, you could experiment some to find the optimum feed rate with little hassle. This would be much easier and less expensive than buying another motor.

 

[shushikiary]

Good idea, I'll have to try it, I can run to lowes and pick up some sheet metal and mod my hopper.


The other option I suppose would be to increase my gap from .035 to .040 or something like that, which might help a fair amount as well.... But I get such an amazing crush with .035 and conditioned malt .

 

[Catt22]

Good idea, I'll have to try it, I can run to lowes and pick up some sheet metal and mod my hopper.


The other option I suppose would be to increase my gap from .035 to .040 or something like that, which might help a fair amount as well.

Widening the gap would definitely reduce the required torque, but I would want to be able to set the gap wherever desired without having the motor being the limiting factor and requiring some kind of a compromise. I think you will find that choking down the feed rate will work like magic and you will still have plenty of through put.

 

[BrewBeemer]

I was thinking this also Catt22 with narrowing down the feed but this would apply wear on the knurling on a smaller section of the rollers. No can do, plan "B".
What about adding a 3/8" diameter rod parallel to the rollers above them
in the hopper, add a throttle plate the width of the hopper where it's located plus the full length of the hopper. This way you will be able to restrict the grain flow to the rollers vs compacted by the grain weight in the hopper plus still utilize the mills full roller width.
Think an hourglass, you have flow but reduced as an example.

 

[RDWHAHB]

I am surprised conditioning ups the torque that much. I had zero problems on dry grain (2 roller, 2"). I'll have to condition some and see what happens on mine. Any theories why it ups the torque requirements?

 

[RDWHAHB]

Tried malt conditioning. 600g grain, 12g H20. Wow, conditioning does kinda rock. Where did the flour go...?
Gap set at .039. It could stand to be tightened up (.035?) w/ the conditioning. I'll try that next time.

 

[BrewBeemer]

Conditioned grain acts like chewing gum and lingers with resistance vs dry grain that cracks instantly unloading the mill of required torque. I was told this years ago by an employee at Anheuser Bush that home brewed.

 

[shushikiary]

When the malt is conditioned the whole thing has to be squashed and that's why it takes more torque. When it's dry the husk shatters and then it's easy to push through, but when that doesnt happen due to the conditioned malt it's a lot more work.


Well I didnt have any 3/8 rod, but I did have 1/8 thick 1/2 wide alumunium bar and so I cut a slit to hold it and put it in about 3 inches above the rollers and seems to work. Though I went through all my grain before then I put the already crushed grain back through it and it did just fine. I'll have to get some more grain and condition it again to see, haha. It leaves about a 1/2 channel on each side of the bar for the grain to pass through.

 

[BrewBeemer]

Your on the right track, keep testing.

 

[RDWHAHB]

Makes sense. Do you see a noticeable crush improvement w/the 3-roller? Granted not too many folks have a 2 roller and a 3 to see them side by side.

 

[shushikiary]

Well, I dont own a 2 roller, but I can tell you that my LHBS has a 2 roller MM with 1.5 rollers. Not sure what his gap is set at but I always had tons of husk shreds on his mill when we ran it dry. That vs my 3 grain mill... I had flour at .035 without conditioning, and I mean pure flour, almost no husks intact.

With the 3 roller and the conditioning I get almost no shattering of husks and the grain is split almost down the middle and then pushed apart like someone split it with a knife and pried it open. It comes out very nice.

I was listening to a strong brew pod cast today on milling and they said that the reason for a 3 roller mill is because not all grain is the same size, so the .06 pre crush gets all the grain to under that size before you crush so you dont oblitherate the larger grain with the smaller crush. It pretty much just gives you a more consistent crush than a 2 roller mill, but it isnt a requirement or anything, you'd be just fine without it. I doubt people really have an issue with inconsistant grain size, haha.

Also, with the setup you have, sense you have that small opening showing up to your mill, you most likely wont have any torque issues sense you use such a small portion of the rollers. On mine the MM hopper uses about a 8 inch wide section of the roller.

 

[ClaudiusB]

What about adding a 3/8" diameter rod parallel to the rollers above them
in the hopper, add a throttle plate the width of the hopper where it's located plus the full length of the hopper. This way you will be able to restrict the grain flow to the rollers vs compacted by the grain weight in the hopper plus still utilize the mills full roller width.
Think an hourglass, you have flow but reduced as an example.

Like my mill?

Well, tested the mill.... 90 inch pounds still isnt enough.Well, tested the mill.... 90 inch pounds still isnt enough.

To me your torque requirement sounds too much.
My mill does not come close to 30 in/lb running torque.
I would measure the torque requirement of your set-up without grain first, should be very low.

Cheers,
ClaudiusB

 

[BrewBeemer]

Like my mill?

To me your torque requirement sounds too much.
My mill does not come close to 30 in/lb running torque.
I would measure the torque requirement of your set-up without grain first, should be very low.

Cheers,
ClaudiusB

Perfect!
Now slip tubing over the rod screwed to the rod on one side to produce an eccentric adjustment to vary the feed restriction.
That looks like 3/8" rod by the picture (guessing here), add 3/4" tubing with external arm to adjust and lock the setting.

What is the dimensions of your hopper, angles, height plus how many pounds will it hold?

 

[shushikiary]

The free running torque is pretty much not measurable... besides the fact that I have no way to measure it. But it spins freely by hand.

Dry grain runs just fine, no issues what so ever, it's after the grain has been conditioned that's the issue. It might also be my impatience and running the grain while it's still a little damp after conditioning.

 

[ClaudiusB]

The free running torque is pretty much not measurable... besides the fact that I have no way to measure it. But it spins freely by hand.

Dry grain runs just fine, no issues what so ever, it's after the grain has been conditioned that's the issue. It might also be my impatience and running the grain while it's still a little damp after conditioning.

You can use a fish scale and a string to do it.
Measure the motor current to see how close you are to the full load current, my poor mill does it with 16-in/lb running torque.
Conditioning or wetting the grain does not effect my mill, based on only two tests I ran (including current measurement).
What is hard on my mill is glassy (steely) grain, requires a lot more torque than mealy grain and won't start my mill with grain in the hopper.

Perfect!
Now slip tubing over the rod screwed to the rod on one side to produce an eccentric adjustment to vary the feed restriction.
That looks like 3/8" rod by the picture (guessing here), add 3/4" tubing with external arm to adjust and lock the setting.

What is the dimensions of your hopper, angles, height plus how many pounds will it hold?

Carl no feed adjustment required, mill is happy
Hopper capacity close to 2 kg, 45° angle, not made for wet milling

Cheers,
ClaudiusB

 

[Catt22]

Dry grain runs just fine, no issues what so ever, it's after the grain has been conditioned that's the issue. It might also be my impatience and running the grain while it's still a little damp after conditioning.

The grain should be ready for milling soon after conditioning if it has been mixed well. I usually add the water and let the malt hydrate overnight in a covered bucket, but I've also milled it almost immediately (10-15 minute rest) with little noticeable difference.

 

[BrewBeemer]

You can use a fish scale and a string to do it.
Measure the motor current to see how close you are to the full load current, my poor mill does it with 16-in/lb running torque.

Carl no feed adjustment required, mill is happy
Hopper capacity close to 2 kg, 45° angle, not made for wet milling

Cheers,
ClaudiusB

That's really amazingly low tq numbers.
Conditioned grain I bet requires 60 degree hopper angles preventing sticking plus grain flow interruptions to the rollers.
I have a spare Winsmith 40:1 worm box .86 HP 1750 input, 989 in/lb output this should break something.

 

[shushikiary]

Success! With the throttle bar in place I crushed 3 lbs of conditioned grain in about 45 seconds, 1/3 of that was wheat too, haha.

 

[BrewBeemer]

Thanks for posting your results, that will be a couple bottles of dark porter or stout sent to my island.

 

[MX1]

https://www.surpluscenter.com/item.asp?item=5-1098&catname=electric

Boom!

Any one know how many watts this pulls?

Tim

 

[BrewBeemer]

P=I x E, watts = current x volts, 218.5 watts for that motor.