Motorized Monster Mill Build MM3-2.0

[Robg773]

After a ton of research or over-research, I finally built a motorized grain mill. Here are my thoughts as well as my build.

Parts List
MM3-2.0 Mill with hopper and extension from Monster Mill

1hp 1725rpm 115/230VAC 56C frame motor from ebay (see picture below, any motor meeting these specs will do)

10:1 Gear Reducer 13-175-10-L-56C from Surplus Center

Mill coupler LoveJoy P/N L-095-.500

Reducer coupler LoveJoy L-095-.875

Spider that installs between LoveJoy couplers L095 series

Drum Switch 2 X 440 from Dayton


I used a MM3-2.0 mill. I chose this mill because I got tired of waiting on a chance to get the Rebel Mill so this was the most durable and best choice I found looking for something durable and for long term use. I also bought the base and hopper with extension. The mill has a 1/2inch shaft.

I used a 1hp motor with 1725 rpm 115/230VAC 56C frame. Monster Mill recommends a 1hp motor if you’re using their MM3-2.0 mill. I wanted 115VAC motor so I can just plug it directly into any wall outlet. 1725rpm is important because it allowed me to use a 10:1 reduced which changed my motor output speed to 172.5 rpm. Good rpm speed for milling grain. The 56C frame was also important because the 10:1 reducer I used was also a 56C frame so they mounted up directly using 9/16 bolts.

10:1 reducer with input 1725 rpm and output of 175rpm torque 515in lbs, plenty of power to turn the mill. I fill the hopper before I start the mill and no problem starting the milling with a full hopper, very impressive.

To mate the shaft of the mill with the shaft of the reducer I used Lovejoy couplers. On the Mill shaft I used coupler p/n L-095-.500 and on the reducer shaft I used coupler p/n L-095-.875. On the inside of the coupler is a spider, L095 series, which mates between both couplers to absorb vibration.

To turn my mill on I used a Dayton 2X440 drum switch. This switch was rated at 1.5hp and 115vac. It’s made for electric motor control and allows me to have both forward and reverse. I chose to wire my motor to have a reverse position because I’ve read that sometimes the motor could get stuck on a hard grains and also because I could. J If I ever need to reverse the motor I have the ability. I included a wiring diagram below.

I added a chute, made from shower liner from home depot, that extends about 2in into my 5gal grain bucket as to reduce any grain splashing. Also used metal piping to cover my wiring making for a cleaner look. I put a few coats of laquer semi-gloss on the table as well.

Dayton 2x440A Wiring for forward and reverse

1 2
3 4
5 6

1 L2 (wht) & T2 (wht)
2 T4 (yel)
3 T5 (blk)
4 T8 (red)
5 T1 (blu)
6 L1 (blk) & T3 (orn)

Any questions just ask. View attachment ImageUploadedByHome Brew1428527839.500830.jpgView attachment ImageUploadedByHome Brew1428527877.591158.jpgView attachment ImageUploadedByHome Brew1428527972.929312.jpgView attachment ImageUploadedByHome Brew1428528006.657988.jpgView attachment ImageUploadedByHome Brew1428528043.337187.jpg

 

[normonster]

Awesome!!! I'm going to eventually do the same with my MM2. Not before burning up my current drill and two more though....lol

Great build.

 

[dfess1]

I did the same, but mounted to a piece of aluminum plate. Then built a cabinet it sits on to knock down on the dust. Originally we designed it to straddle some saw horses.

 

[30Bones]

Very well done. Make mine look hack at best.

 

[BrotherGrim]

What were your costs on this build if you don't mind sharing?

 

[Robg773]

Approx cost is $835 plus the cost of the table.

Motor $120
Mill with accessories $450
10:1 reducer $130
Lovejoy couplers plus spider $60
Drum Switch $75

I didn't plan on spending this much i just wanted to have a low maintenance grain mill that would last years to come. I'm an engineer so I tend to overthink things. There are plenty of ways to make it simpler and/or do it cheaper. Table could have been smaller. I had a wooden ramp under the table for the grains to hit and transfer to a bucket but grains were hitting off the ramp and going everywhere so i built the chute. I could have used a cheaper switch with only fwd position. So i went a bit overboard in some areas but it turned out good and i think it will last a few years.

 

[HerkDriver]

Congratulations on the build! That is a very clean install. I especially like the wiring coming from underneath the table. I have the same parts on my workbench after a furious night of impulse purchases after reading drunkenmonk's writeup of his build. I am thinking of putting the motor/mill/gearbox on one of these:

http://www.samsclub.com/sams/ulhd-2...449&selectedTab=allProducts&_requestid=397276

That will definitely last for years. Would you mind terribly posting a few more pictures of your work underneath the table top for the liner and the switch wiring?

 

[Robg773]

Nothing special here just tried to make wiring neat. Regarding the chute, its basically a shower floor liner ftom home depot cut and sandwiched between two pieces of wood then screwed into the underside of the table. Cleaned liner with alcohol first though.
Your table looks fine. It'll work as mu table coulda been smaller.
If you need more pictures let me know.

View attachment 1429759122818.jpg

View attachment 1429759132353.jpg

 

[HerkDriver]

Thanks for the pics, as soon as I have a free weekend I'll post something about my build progress. Let me know if you have any issues with your setup.

 

[BadWolfBrewing]

looks great. I'm leaning toward a gear reducer as well. Giant spinning sheaves of death worry me a little. I frequently have drunk 'brewing assistants', and their wives would kill me if fingers were lost.

 

[Robg773]

Yes exactky why i went with a gear reducer. Cleaner look, safer, no rpm caculations. I got the gear reducer from surpluscenter.com if that helps any. With the reducer you're going to need couplers to mate the reducer output shaft with the grain mill shaft.

 

[Stealthcruiser]

Split a piece of tubing, Please, and slide it over your wiring, where it passes through the pipe elbow, so there's no chance of the wiring chafing on the threads!

 

[rekoob]

Nice looking project, well done.

 

[Robg773]

Good idea stealthcruiser...the wiring isn't stiff so i didn't worry about chafing. Will do thanks.

 

[DarkMule]

Awesome info, thanks very much. First class project!

Two questions:

1. How did you mount the Dayton switch, there are only two mounting holes, but I am not sure how they would work, as there is little clearance.

2. Does the lovejoy coupling's set screw grip enough on the mills shaft or did you modify the shaft?

I have everything I need to start building this weekend!

 

[Robg773]

1. I used two wood screws. There will prob never be any pressure on the switch housing so it prob will never move.
2. Very good question. I actually messed this up initially. The set screw won't grip the shaft enough. I couldn't get it tight enough. I used a 1/2in grade 8 bolt I think. Homedepot sells a silver grade 5 and a bronz/gold grade 8. I had the silver grade 5 in initially but it wasn't tight enough. I used a socket and ratchet to get it tighter and broke the head off the bolt and had to use a reverse tap to get the bolt out of the coupler. Got the grade 8 bronze /gold bolt and tightened it down with the ratchet and now it doesn't slip at all.

Hope that helps.

 

[DarkMule]

That is very helpful. Thanks for sharing!

 

[BungBrewing]

...10:1 reducer with input 1725 rpm and output of 175rpm torque 515in lbs, plenty of power to turn the mill. I fill the hopper before I start the mill and no problem starting the milling with a full hopper, very impressive...

How did you calculate the torque?

 

[Robg773]

Wish i could take credit for being that smart lol. The spec sheet for the 10:1 reducer lists an output soeed of 175rpm max and output torque of 515in-lb max.

 

[BungBrewing]

Wish i could take credit for being that smart lol. The spec sheet for the 10:1 reducer lists an output soeed of 175rpm max and output torque of 515in-lb max.

Ah, now it makes sense... Unfortunately that's the output maximum of the gearbox, but I think it takes a 1.57 hp motor to develop that amount of torque... Unless I'm mistaken, your motor would have about 350-360 in-lbs of torque, which is still a quite a bit...

 

[Robg773]

Good point. Did you do a torque caculation based on hp and rpm? Or a ratio based on relationship of hp and output torque?

 

[BungBrewing]

I hope this is correct:

(5252 x hp) / rpm = T (Ft-lbs) x 12 = T (in-lbs)

 

[Robg773]

That looks about right. I'll buy it. Thanks for pointing that out.

 

[asoltero213]

I love how the switch looks... how did you know if your motor could go reverse or not?

 

[Robg773]

The side of the motor says for ccw wire this way and for cw swap these two wires.

 

[Floridagator]

The whole setup is very nice, but I'm most impressed with the table. It looks very clean. Would you mind sharing dimensions and the type of wood you used?

 

[Robg773]

Sorry for the delayed response but the table top is 2ft by 4ft. One solid top and the rest is made from pine i think. If i had to build again i would probably make the footprint of the table smaller. I can take more pictures of you like.