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Monster Mill 3 troubleshooting

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I've tried adjusting, re-adjusting, tightening, loosening....
I'm throwing in the towel on the MM3.
I've made great beer with a 2 roller mill. Guess that's my plan B.
I'm no stranger to motorized grain mills, but not arrogant enough to still consider it's some sort of setup error on my part, but this is thing is just too finnicky. Not worth tearing my hair out over. (what little is left)….
I REALLY appreciate the responses and help here.
Thank you all !

One more suggestion for you: Assuming you can remove the pulley and get it down to just the roller shaft, have you tried using a drill to power this, i.e., taking off the sideways pressure the pulley system produces? If you do that and you still get binding after adjustment, then it's the mill that's the problem. If the problem goes away, it's the use of a pulley system that is the culprit (somehow).

And: I can't recall who manufactures the MM3, but have you contacted them about this? Maybe the specific unit you have is defective.
 
Well I for one am glad this thread was started. I bought a MM3 a few years ago and recently upgraded from 5 to 10 gallon batches. My drill was a cheapy and started over heating on the bigger grain bill. I motorized mine, but the exact problem that you describe staryed happening to me. I'd have to reach under the mill and spin the bottom roller by hand with the motor running to get it going. Always envision being eaten by the damn thing when I do that. Loosened up the bolts and now it's working like a charm.

Thanks all
 
I would suggest contacting Monster Brewing hardware.. There may be a defect in your mill. They may have suggestions to lead you to the problem.

MM is one of the most highly respected mills made. Your problem is not typical.
 
One more suggestion for you: Assuming you can remove the pulley and get it down to just the roller shaft, have you tried using a drill to power this, i.e., taking off the sideways pressure the pulley system produces? If you do that and you still get binding after adjustment, then it's the mill that's the problem. If the problem goes away, it's the use of a pulley system that is the culprit (somehow).

And: I can't recall who manufactures the MM3, but have you contacted them about this? Maybe the specific unit you have is defective.

Yup. See post 20.
This is my second one. I returned the first one to MoreBeer who were very nice about it.
On the first one, right out of the box, with the set thumb screws tightened all the way, I could still freely turn the gap adjusting knobs.
 
I did contact Monster Brewing Hardware and exchanged messages with Fred.
He gave me some suggestions, same as the posts here.
 
@SEndorf, perhaps I missed it in a post somewhere, but you are adjusting the gap on both sides of the bottom roller, correct? It appears others had experienced similar issues until they set the bottom roller to the lowest point possible and then adjusted from there. Not that .008 should make a difference, but the MM-3 video on their website suggests starting out with a .022 + .018 = .040 gap size.

https://www.monsterbrewinghardware.com/store/pc/MM-3-p86.htm

https://www.homebrewtalk.com/forum/threads/3-roller-monster-mill-help.255840/

I realize you are frustrated, but I wouldn't give up quite yet. What are the odds of receiving two faulty MM-3? Maybe MB received a bad manufacturing batch if ultimately that is the issue. When you received the second MM-3, was it in a sealed box? MB accidentally sent me a returned bench bottle capper. They quickly rectified their mistake. MB is a great company and will work with you, even if it means sending you another MM-3.

I have the MM-3Pro and it performs flawlessly.
 
Be sure the rollers have some play in the end blocks and are not binding.

Be sure to set the gap between the driven roller and the bottom roller properly.

Monster has a you tube video on this ....it’s critical.

Again, if the mill side plates on the roller are tight, the mill will bind, perhaps this is why the factory base has oversized holes. The rollers should have some slack or space within the end blocks of the mill....important!!!
 
I've tried adjusting, re-adjusting, tightening, loosening....
I'm throwing in the towel on the MM3.
I've made great beer with a 2 roller mill. Guess that's my plan B.
I'm no stranger to motorized grain mills, but not arrogant enough to still consider it's some sort of setup error on my part, but this is thing is just too finnicky. Not worth tearing my hair out over. (what little is left)….
I REALLY appreciate the responses and help here.
Thank you all !

Almost guaranteed to be an error on your part, but i agree with your sentiment that its difficult to set up. I am mechanically and technically inclined and i pissed away a lot of my time getting it just right.

IMHO their fail is that they should provide a metal base plate to align the frame pieces they provide, and that base plate should be independently attached to whatever. Also what for what they charge some real bearings instead of bushings would be nice.
 
.025"? This is very fine. Didn't this produce flour from the grain?

Yes, it produces a lot of nice flour, which I use with my single vessel BIAB rig to get a brewhouse efficiency of ~83%. That's with no sparging, no re-circulation. If you think the beer comes out cloudy, or has taste problems, that is not the case.

IMG_20190122_161601_208.jpg

No finings of any type were used in that beer, just a cold crash for a few days after fermentation.
 
I was a MM in the Navy and a Millwright after that. Installed pumps and motors and other stuff. You must have a pillow block bearing on the out side of the pulley on the mill to keep the shaft from flexing!!!!!!!!!!!!!! If you don't do this and you get the mill to work,eventually it will destroy the bushing on the mill.
Yes I second this... MM sells an upgraded version of the 2 roller pro mill with bearing for belt driven applications... its only like $400 plus shipping with the hopper.. Or you could just have bought the $150 kegco 3 roller with ball bearing but its a bit late for that now..
Dont take this the wrong way but I have a feeling though that if you had bought the kegco you might still have this problem if it is self induced somehow and everyone would be blaming on the "cheap" chinese mill. As they did in another recent thread that sounds like op had similiar issues with the kegco.

For what its worth I have the 3 roller kegco and have the rollers/gap as far open as they will go because of a very poorly designed false bottom in my 3bbl mash tun I need to replace. We do still manage an average of 85% efficiency though.
 
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I had a bitch of a time setting up my MM3-Pro when i got it. Turned out the solution was to not tighten the bolts. They're a bit more than finger tight. That plus a little wiggling until the rollers spun freely and it works great. Their hopper also has a tendency to put the base into a bind. Not a single screw or bolt in the entire thing is tight otherwise it binds right up.

This ^^^^ 100%!!
 
I had a bitch of a time setting up my MM3-Pro when i got it. Turned out the solution was to not tighten the bolts. They're a bit more than finger tight. That plus a little wiggling until the rollers spun freely and it works great. Their hopper also has a tendency to put the base into a bind. Not a single screw or bolt in the entire thing is tight otherwise it binds right up.

How are you powering the mill?
I think loose bolts would be a plus for a lovejoy coupling or a drill.
The lateral pull of a belt pulley would really yank the mill sideways.
 
FWIW.… I finally got my setup done with a MM2, a gear motor running 60 inch pounds, and a lovejoy coupling.
This thing cuts grain like melted butter.
Funny thing is it's the same motor I had with the MM3. Frankly, I think the 3 roller mill is best suited for a drill.
I'd like to sell the MM3. If anyone's interested, I'd be glad to unleash it. It's all boxed up and ready to go.
Message me and you'll be happy...….
 
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