What RPM do you run your grain mill at?

I'm out of wall space



The cabinet is more or less done... just window dressing at this point, so I figured I'd post a few more photos and wait patiently for your praise...


all closed up



assembly



chute door closed



Chute open and ready to go



That's about it.... did a test run and it was crushing at a rate of 5lb/min.

My drill does not have enough torque.....will look into the motor drive in a few months, out of money right now...lol

Tim

bbognerks said:

I checked these tonight. The Barley Crusher is 3/8, but VERY tight. I had to tap on it a bit to get it on. The motor is 1/2 and not nearly so difficult to put on.

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Thanks for the info! would you have went with the bigger size for the BC if you had a do over?

No. If you go with the bigger size, I would think it would make it lopsided. There is only a single set screw on the collar, so it needs to be pretty tight to be centered. 1/2 would have been way too big. If it's too tight, just take some sand paper/emery cloth to it. That's what I did and it worked a treat. I still had to tap it on, but it was very minimal force.

Seabee John said:

I'm out of wall space

That's about it.... did a test run and it was crushing at a rate of 5lb/min.

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That's really nice Seabee John. Very well done.

RDWHAHB said:

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.

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I feel sorry for those rollers as 500 ft/lbs TQ would snap 2" in half unless they were made of 4130 ir 4140 chromoly steel. The motor must be mounted on 2" box tubing 3/8" wall thickness, thinking a 482" FE engine to maintain those torque numbers and around the 3,700 rpm range. Storage of a 1,000 pound grain mill must be considered also.

BrewBeemer said:

I feel sorry for those rollers as 500 ft/lbs TQ would snap 2" in half unless they were made of 4130 ir 4140 chromoly steel. The motor must be mounted on 2" box tubing 3/8" wall thickness, thinking a 482" FE engine to maintain those torque numbers and around the 3,700 rpm range. Storage of a 1,000 pound grain mill must be considered also.

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Thanks. I thought I already made the public record of my idiocy fairly clear...but that clear it up for those who weren't sure.

Toss in "in/oz" or Nm torque numbers enough for the brain to explode.
I was just picking on ya, it's my nature to have fun and tease people that can't hit back like the wifey.
On my MM3.2 it is planned with turning at 110 rpm's, I can wait while the MLT is
heating up having the bare minimum of flour produced. The bushings will like this lower rpm also plus the crush results vs milling or shredding at higher mill rpm's.
Do not forget those family or curbside threadmills as they have 1 1/2 to 3 HP 90 VDC motors with a heavy flywheel and speed control that maintains constant rpm no matter the loading torque applied. They can work as a variable rpm mill motor if you include a jackshaft, cheap or as freebies helps the build.

Tease? I don't recall any funbags in your post.

bbognerks said:

Tease? I don't recall any funbags in your post.

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The fun begins especially during summer months around the freezer sections of grocery stores. I wired up many Hussman cold sections, plenty of eye candy you bet. Hell met the wife looking around that way.

no worries. Looking awesome Seabee

Great looking build, Seabee! Love the chute instead of the "drop into bucket" design!

Got around to making a new base and hopper. Put the motor on too. No problem starting loaded! Pics to follow.

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.

Seabee John said:

I'm out of wall space

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Not unless your ceiling ia already occupied with equipment pulled up by small block and tackle units.

shushikiary said:

Just a heads up for you guys, I have a 42R-E bodine motor with almost the same specs as the one you bought, but it's 45 inch pounds of torque instead of 40 and 170 RPM. Here it is: http://www.bodine-electric.com/Asp/ProductModel.asp?Context=8&Name=42R-E%20Series%20Parallel%20Shaft%20AC%20Gearmotor&Model=0680&Sort=11166

I have it hooked up to a monster mill 3 roller mill with the normal sized rollers but SS. It's direct drive with a L90 love joy connector, 1/2" on the MM drive shaft and 3/4 on the motor.

45 inch pounds of torque just isnt enough in direct drive.

I've ordered (but have not received yet) some ANSI 25 chain sprockets from mcmaster carr that will allow me to double the torque and halve the RPM. (18 tooth for the 3/4 and 36 tooth for the 1/2), ANSI 25 chain is rated for 140 pounds of sheer, so it should be fine sense 90 inch pounds is 8 foot pounds of torque.

Hopefully that will solve my mill binding issue with conditioned grain.

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It's a bad idea to have sprocket drives that repeat for set in wear purposes, odd count for even wear sprocket wear like 26:53 vs 26:52.
Your MM 3 roller 1.5" or 2" diameter rollers? Your talking 1.33% more torque required turning 2" vs 1.5" rollers.
Adding a chain and sprockets would be a bad idea your dealing with flour dust and grain grit wearing away the lubed chain drive system.
I would use HTD8 Timing belt with sprockets or better yet L Timing belt with sprockets in 1/2" or 3/4" width.
A dry clean long life system even under these abrasive conditions.

BrewBeemer said:

It's a bad idea to have sprocket drives that repeat for set in wear purposes, odd count for even wear sprocket wear like 26:53 vs 26:52.
Your MM 3 roller 1.5" or 2" diameter rollers? Your talking 1.33% more torque required turning 2" vs 1.5" rollers.
Adding a chain and sprockets would be a bad idea your dealing with flour dust and grain grit wearing away the lubed chain drive system.
I would use HTD8 Timing belt with sprockets or better yet L Timing belt with sprockets in 1/2" or 3/4" width.
A dry clean long life system even under these abrasive conditions.

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I've shown how savvy I am at gearing, but 1.33% sounds low to me.

RDWHAHB said:

I've shown how savvy I am at gearing, but 1.33% sounds low to me.

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My bad, 1.33 times more TQ to drive 2" vs 1.5" roller mill.
I have a industrial sealed 1/3 hp Baldor with Precision Gear worm drive
mounted as a single unit, dang thing only has 29.16 rpm output at 565 in/lbs TQ.
I'll have to gear it up, thinking 3/4" L Timing belt to 110 rpm's, this will drop the TQ down to 149.77 in/lbs for the MM3-2.0 mill. I believe is should handle it even starting with a loaded hopper. For free I can't complain as it listed over $700.

BrewBeemer said:

Not unless your ceiling ia already occupied with equipment pulled up by small block and tackle units.

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I've got overhead racks for lumber storage, ladder storage, and a f' load of lighting... so yeah... I'm out of space. Floated the idea of building a shed past the SWMBO today... you know... for the yard tools and such... My idea was not well received. She said it was time to focus less on building "my" stuff and start working on building "her" stuff.

oh the drama

Seabee John said:

Floated the idea of building a shed past the SWMBO today... you know... for the yard tools and such... My idea was not well received. She said it was time to focus less on building "my" stuff and start working on building "her" stuff.
oh the drama

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This is proof all women's minds are interconnected to each other.
I can't talk my 19' kayak is hanging from the garage ceiling (bad back but can not part with it) plus many other large items, BMW fairings of the 70's $$$$$$$.
The large tool shed requiring power, water, gas heating and drain didn't make it past the War department at this end.
If I could only buy the neighbors house and knock it down for a 10 car garage, shop off the side, brewery on the other side. The pisser they keep the 3 car garage empty, lawnmower rake and broom, I can taste the extra storage.
Lack of funds stopped that idea at the dream stage.
Sunny weather the 60's plus for weeks, 1 1/2" rain to begin tomorrow AM.

RDWHAHB said:

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.

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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.

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

M_C

RDWHAHB said:

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.

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Misplaced_Canuck said:

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

M_C

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

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

M_C

bbognerks said:

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

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Catt22 said:

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.

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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.

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.

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.

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.

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.

shushikiary said:

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.

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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.

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 .

shushikiary said:

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.

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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.

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.

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?

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.

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.

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.

Your on the right track, keep testing.

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.

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.