Shiny New Mill... To Motorize or Not to Motorize...

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vonZwicky

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I just received my brand new Crankandstein 3 roller mill, and I'm feverishly researching the forums here- looking at the fine work of others and trying to decide on how I want to proceed with a build for a base and hopper, possibly motorized.

I do have the very simple base and hopper that Crankandstein offers, and a drill, so I'll be able to use it that way in the short term- but I don't think I'll be able to overcome my nagging desire to MODIFY. I want to build something really cool!

It would be nice to have a mill that would work without electricity, so it will function off the grid, or after the Apocalypse, when the grid is no more. But handmilling grain sucks... unless the process could be MODIFIED.

This is my idea- design the mill to work with a handcrank, but give it a mechanical advantage so the chore is not so arduous. It would employ a large and a small sheave, just as many of the motorized ones I've seen here, but the small sheave (3" diameter)would be on the mill, and the larger one (let's say 12") would have the handcrank to power the mill:

img1950i.jpg


Every turn of the crank would result in four rotations of the rollers. So, if you could manage 1 turn per second, that would drive the rollers at 240 rpm (more than fast enough). I think it would help if the large sheave had a fair amount of mass, to work as a flywheel and provide torque.

I've searched and not found another example of this type of setup. Has anybody done something similar to this? I'm certainly no mechanical engineer... Is there some reason why this would be impractical? Any input would be appreciated. Thanks!
 
Sorry about that... I realized the image was too large as soon as I posted. I edited the pic. Should be good now.
 
My biggest concern is that it would be to hard to crank. From what I understand, gearing up to increase speed reduces torque.

I suppose I could acquire the pulleys I need, set them up just enough to test the mill. If the method doesn't work well, I can use them to gear down a motor.
 
I don't see why you can't. My setup is the inverse as far as pulleys because I have a motor. It should work the other way around.

The only problem might be the torque required to turn your hand crank. Imagine what it would be like to turn the Crankenstein if it was three times harder. If you are OK with that then go for it.

My JSP Maltmill was hard enough to turn when loaded with grain out of the box. A fourteen pound grainbill would leave my bicep and deltoid burning. I can't imagine it with three times that resistance. YMMV.
 
It's a trade off. More torque means easier crushing at a reduced rate, so it takes longer to crush.

I had recently thought about building a flywheel onto a hand-cranked crusher and maybe rig up a foot pedal like an old sewing machine, to keep it going. It's GOT to be easier than cranking by hand, and not that hard to build either.
 
Your circumference calculations are not correct, but it doesn't really matter as your ratio of 4:1 will be the same. (it's simply the ratio of the sheave diameters; Pi isn't necessary in the calcs as it is a constant and cancels out in the division)

Pi X D = Circumerence ie 12 X 3.14 = 37.8 inches
and 3 X 3.14 = 9.4 inches

37.8/9.4 = 4.02

Having the large sheave driving the smaller on on the mill will increase the required torque by your 4:1 ratio and this will make it very hard to turn. You could achieve the same effect using a very short crank handle. IMO, this is not the way you want to go. It will require a lot of force to turn that thing. Much more than I would want to deal with.
 
I wish I had the time and spare parts/$$ to buy parts to hook my mill up to my roadbike trainer. 20-30 minutes of stationary biking to grind a 25# grain bill? No problem!
 
Your circumference calculations are not correct, but it doesn't really matter as your ratio of 4:1 will be the same. (it's simply the ratio of the sheave diameters; Pi isn't necessary in the calcs as it is a constant and cancels out in the division)

You are most correct, Catt22. How foolish of me. Circumference is equal to 2*pi*r, not 2*pi*d. I did realize as soon as I did the math, that simply using the ratio of the diameters would suffice- the relationship of diameter to circumference is directly proportional... area of a circle is another mater.

I've also come to the conclusion that this is probably not the way to go. It would be too hard to crank, and space for storage is a big issue with everything I've been building for my brewery... If I can do away with large pulleys altogether, I can make this project much more compact, and safe. I'm already shopping around for an appropriate motor (+gearbox, perhaps). It may take a little time, but I expect this to turn into a build thread (with pics), once I get all the parts together.

Thanks for the input, guys, into this, and the other mill-related threads I've been reading.
 
I wish I had the time and spare parts/$$ to buy parts to hook my mill up to my roadbike trainer. 20-30 minutes of stationary biking to grind a 25# grain bill? No problem!

I've seen one or two others take this approach on this site... the idea does have some appeal. What would be too difficult to achieve by hand cranking could easily be achieved with leg power.
 
It's a trade off. More torque means easier crushing at a reduced rate, so it takes longer to crush.

I had recently thought about building a flywheel onto a hand-cranked crusher and maybe rig up a foot pedal like an old sewing machine, to keep it going. It's GOT to be easier than cranking by hand, and not that hard to build either.

I like this idea... it would be a little more compact than the bicycle rig. Probably won't go this route anytime soon, but I'll file the idea away for future tinkering when I have the space, or after the Apocalypse.
 
There is always the option of a Solar or Wind backup power source if you want to go off the grid.
 
Got a stream running through your property? If so, do it the authentic old fashioned way with a water wheel. Now, that would be tits, IMO. Wind power as in Holland style windmills would also be very cool.

A big flywheel is not really a bad idea if one had the space. I could see a 24" diameter x 36" long concrete flywheel running on ball bearings. Get that thing spinning somehow and it would be nearly unstoppable. You could draw off power with a friction drive which could be nothing more than a rubber tire mounted on the mill shaft somehow and rubbing against the flywheel. Now, moving the flywheel around could be problematic, but it could be built and mounted outdoors or something. OTOH, a Harbor Freight drill motor for $39 would be a smarter way to go IMO.
 
I do live on a bayou, but at the rate it flows, it would have to strain against a paddle wheel all day long to crush a single kernel of barley. A wind mill would be awesome- There is almost a constant breeze here due to my proximity to the Lake.

These are all fun ideas to ponder, but I think I'm gonna try to keep it on the grid, for now. Something small, reasonably portable, and that I can plug in.

The drill method would be the easiest and most economical. But almost all of my brewery projects have been over the top so far (which, to me is a lot of the fun). I doubt this build will be any different.
 
I do live on a bayou, but at the rate it flows, it would have to strain against a paddle wheel all day long to crush a single kernel of barley. A wind mill would be awesome- There is almost a constant breeze here due to my proximity to the Lake.

These are all fun ideas to ponder, but I think I'm gonna try to keep it on the grid, for now. Something small, reasonably portable, and that I can plug in.

The drill method would be the easiest and most economical. But almost all of my brewery projects have been over the top so far (which, to me is a lot of the fun). I doubt this build will be any different.

I hear ya! I've been addicted to gadgets since early childhood. We forgot to mention steam power. Now that would be sweet. I can see right away that a 10 minute milling job could turn into an all day operation using a steam engine. The steam whistle alone would make it a worthwhile project.
 
Just use a GEARMOTOR to drive your mill. Cheap and easy to do.

Thanks PJ. I've seen the link for this motor on one of the other threads and the price is nice... but I've also read that the torque may be a little low, especially for a three roller mill. Or, as my dad might say, "Son, that motor doesn't have enough ass to drive that mill!"

I really don't know... Woodworking is my forte, but I'm virtually an idiot when it comes to motors and electrical knowledge in general. I want to build something that will be a showpiece of craftsmanship, and I'll have to build it around whatever components I end up buying. So I want to make sure I'm getting the right parts for the job before I go all out on building a custom base and hopper.

Has anybody else used this motor for a three roller mill? How is its performance? I want mill jam ups to be a very seldom, if ever, occurrence.
 
I hear ya! I've been addicted to gadgets since early childhood. We forgot to mention steam power. Now that would be sweet. I can see right away that a 10 minute milling job could turn into an all day operation using a steam engine. The steam whistle alone would make it a worthwhile project.

Steam would be out of sight! A boiler (preferably wood/coal fired) and steam engine rigged up to handle almost every aspect of brewing, from milling the grain to heating and pumping the wort. Victorian style homebrewing!

Edit: Oh yes, the steam whistle would be crucial!
 
Steam would be out of sight! A boiler (preferably wood/coal fired) and steam engine rigged up to handle almost every aspect of brewing, from milling the grain to heating and pumping the wort. Victorian style homebrewing!

Steampunk! http://www.toxel.com/tech/2009/07/12/12-steampunk-gadgets-and-designs/

I'm very surprised that no one has yet built a full on and fully functional Steampunk home brewery. Seems to me it would be a perfect fit. Some of the systems I have seen are more than half way there already. No, it would not need to be operated with actual live steam, but it would be cool if it appeared that way. The creative possibilities are endless. I've considered building a brewing system along the Steampunk lines, but I presently don't have the room or the budget for it. It will happen eventually, but probably not real soon.
 
I've seen several threads on this forum where brewers have used steam to great advantage in the brewing process. Larger breweries use boilers and steam to heat water and boil wort. I think to qualify as "steampunk," that Victorian aesthetic has to be there... Not only does it have to work good, it has to look good. Fine woodwork and brass gears don't hurt.
 
I've seen several threads on this forum where brewers have used steam to great advantage in the brewing process. Larger breweries use boilers and steam to heat water and boil wort. I think to qualify as "steampunk," that Victorian aesthetic has to be there... Not only does it have to work good, it has to look good. Fine woodwork and brass gears don't hurt.

Yes, the Jules Verne combination sci fi and history that never was, but could have been are a major part of the Steampunk thing. Much of it has to do with the allusion of functional apparatus, but most of what I have seen is not operational or only partly so. I'm somewhat familiar with the steam injection rigs and how steam jacketed kettles work in larger breweries, but personally I think that live steam is much too hazardous for amateurs. It's fine if you know what you are doing and do it safely, but live steam scares me. I'm a coward when it comes to steam explosions. I readily admit to that. So, if I ever build a Steampunk themed home brewery, it will have all the requisite brass, wood, scroll work, gauges, hand wheels and gears, fire etc, but I won't be using any actual live pressurized steam at all. There will be some non-pressurized steam, but we already have that with our boil kettles, so that's easy enough to do. Wood or coal fuel would be too dirty and difficult to control, so I will probably stick with gas. Might have to simulate some additional smoke somehow. The steam whistle will have to be powered by compressed air. That can certainly be done. Need a bell too like on the older steam locamotives. Clang...clang...clang
 
Steam under pressure is certainly dangerous. The early days of this technology are ripe with boiler explosions. Even minor steam leaks can cause severe burns.

I'd like to see something along the lines of what you propose- a brewery that has the look and feel of "steampunk."

I still get a kick out of the name "steampunk," by the way. About 20 years ago people used the phrase "cyberpunk" to describe the near future. Then about 10 years ago someone used "steampunk" to describe the near past. I had no idea that the name would be more than a fad. It seems to have "stuck."
 
Hmm, What is green?? What is built is already built and should be used to the maximum capacity of its usefullness and not sent to the landfill when there is soo much usefulness remaining.

I got a treadmill motor and controller from a defunct treadmill. 2.5 HP, But I need something to set the speed, possibly just a rheostat from Radio Shack?? I'll figur it out.

It used to be that tractors ran on steam. The farmer would get up about 3AM and light the fire in the tractor, then go in, get breakfast, feed the fire, do some chores, feed the fire, ride the donkey around the house 7 times, then git to plowin'...boy Diesel works too. Shioot I'd rather have a mule than a steam engine!!

Ha. that DFH60 clone is goood!!
 
Just to get back on topic- I want to build a housing for this mill (Crankandstein 3 roller). I've decided that I want to motorize it (direct drive, no pulleys or belts). I want it to be compact, such that it can be reasonably portable. I have a few competing design ideas in my mind, but I will not be able to get started on it till I have all the parts in hand. Right now the biggest question is whether to mount the motor in line with, at a right angle to , or vertically at a right angle to the mill.
 
I think I found a decent price for a new motor... but they are out of stock on the 1/3 hp model. Would 1/2 hp be too much power?
 
I think I found a decent price for a new motor... but they are out of stock on the 1/3 hp model. Would 1/2 hp be too much power?

IMO, No. IIRC, most 110V AC motors are either 1725 or 3450 rpm. If you get the lower rpm version, your sheaves can be smaller for a more compact installation. You will be gearing it down either way, so you should have plenty of torque available with either motor. The 1/2 hp might actually be a better choice power wise.
 
Mill2_002sm.jpg


I don't think you can have too many hP. as long as you can control the speed.

I do really intend to build a grain cart with the 2.5 hp DC treadmill motor I have. I just need to figure out how to wire the controller. I have been told 200RPM is about right. And anyone who can help with this is appreciated.

In the meantime, a 1/2 inch drill is probably the best, cheapest option.
 
IMO, No. IIRC, most 110V AC motors are either 1725 or 3450 rpm. If you get the lower rpm version, your sheaves can be smaller for a more compact installation. You will be gearing it down either way, so you should have plenty of torque available with either motor. The 1/2 hp might actually be a better choice power wise.

Yes, I'm looking at a 1725 rpm motor. I think I'm gonna go with a worm gear box (10:1) over sheaves... for compactness and safety concerns. Might just go with the 1/2 hp model.
 
... I do really intend to build a grain cart with the 2.5 hp DC treadmill motor I have. I just need to figure out how to wire the controller. I have been told 200RPM is about right. And anyone who can help with this is appreciated.

In the meantime, a 1/2 inch drill is probably the best, cheapest option.

Wish I could help you out with this, but I'm just now getting my head wrapped around understanding AC motors and their specs. I wish I did know more about DC motors. Supposedly its easier to reduce the speed on them without the motor overheating? You'd have to have some kind of inverter to convert AC power to DC. But if the motor came from a treadmill, wouldn't something like that already be in the tread mill?
 
Yes, I'm looking at a 1725 rpm motor. I think I'm gonna go with a worm gear box (10:1) over sheaves... for compactness and safety concerns. Might just go with the 1/2 hp model.

Excellelnt choice on the worm drive and 173 rpm would be just about ideal IMO. Where did you find the worm drive? It will inherently give you the right angle offset too which is an added bonus for a more compact configuration.
 
My homemade mill is powered by a free gearmotor given to me by a guy at work. I dont have the specs, but it's small enough to fit on a sheet of stainless right next to the mill. It's a right angle gearmotor, so the space is smaller. The whole assembly, including the switch and hopper can hang on a nail in the garage, and just sits on top of a bucket when I want to use it.

Other than the mill doesn't always grab grain, it works fine. Probably slower than most, but I can fill the hopper and come back in a few minutes and refill. That hopper holds 6 lbs of grain. I should have our Wire EDM guy on second shift cut me a pair of gears to get the idle roller always moving.
 

The motor and worm drive appear to be first class equipment. The prices would stop me dead in my tracks though. Just doing a rough tally, it's starting to look like the total cost for the mill, motor, gearbox, couplers, hopper, shipping etc could exceed $600. Ouch!
 
My homemade mill is powered by a free gearmotor given to me by a guy at work. I dont have the specs, but it's small enough to fit on a sheet of stainless right next to the mill. It's a right angle gearmotor, so the space is smaller. The whole assembly, including the switch and hopper can hang on a nail in the garage, and just sits on top of a bucket when I want to use it.

Other than the mill doesn't always grab grain, it works fine. Probably slower than most, but I can fill the hopper and come back in a few minutes and refill. That hopper holds 6 lbs of grain. I should have our Wire EDM guy on second shift cut me a pair of gears to get the idle roller always moving.

IMO, milling relatively slowly is desirable for several reasons. Less wear and tear on the mill, generates much less grain dust and it's quieter. I'm running quite slow myself at only 115 rpm and about 2+ lbs/min throughput. The slow rate is not even an inconvenience as I can fill the hopper and do something else while the mill is running. I just milled a 50 lb grain bill a few days ago in about 20 minutes. I didn't actually time it, but it did not take very long. I was headed to a group brew that morning. The hopper holds about 20 lbs, so I only had to fill it twice and top it up with the remainder near the end. It was finished milling before I had the snow swept off my truck. The usual problem is getting the mill to run slower, not faster.
 
When I first started using it, and the grain would get caught better, a hopper load would take about 2 minutes I think. 6 lbs in 2 minutes is fine by me.
 
The motor and worm drive appear to be first class equipment. The prices would stop me dead in my tracks though. Just doing a rough tally, it's starting to look like the total cost for the mill, motor, gearbox, couplers, hopper, shipping etc could exceed $600. Ouch!

That doesn't even include the price of the wood, sandpaper, wood finish, fasteners, couplers, switches, wheels (possibly), and my time in labor that will be put into this. It helps that the mill was a gift from SWMBO. Also, I think they may like me at work- my bonus this year was just north of decent. My brewery build has been moving at a glacial pace, just because I'm not in a rush (I'd rather be patient to achieve higher quality), and the high price of my builds are not so bad, when spread out over long periods of time. In the end, I'll get great satisfaction knowing I built something first class, that might last generations without too much maintenance, and that I could possibly sell for at least a fractional recoup if I ever get in a real pinch.

I'll take this opportunity to shamelessly drop some links to some of my other build threads:

https://www.homebrewtalk.com/f51/vonzwickys-keezer-build-158421/

https://www.homebrewtalk.com/f51/wooden-grolsch-bottle-cases-ten-years-making-170733/

https://www.homebrewtalk.com/f51/custom-shelves-brewery-bling-209396/

https://www.homebrewtalk.com/f36/year-zero-day-one-today-210761/
 
IMO, milling relatively slowly is desirable for several reasons. Less wear and tear on the mill, generates much less grain dust and it's quieter. I'm running quite slow myself at only 115 rpm and about 2+ lbs/min throughput. The slow rate is not even an inconvenience as I can fill the hopper and do something else while the mill is running. I just milled a 50 lb grain bill a few days ago in about 20 minutes. I didn't actually time it, but it did not take very long. I was headed to a group brew that morning. The hopper holds about 20 lbs, so I only had to fill it twice and top it up with the remainder near the end. It was finished milling before I had the snow swept off my truck. The usual problem is getting the mill to run slower, not faster.

Catt22, I've been wondering about this... I've heard that somewhere in the neighborhood of 200 rpm is ideal. My current design would put me at 172. Do you think there is an advantage to going even slower than this? Personally, I'm not interested in speed when it comes to milling, just reliability. Would less than 172 result in a better crush with less dust?
 
My homemade mill is powered by a free gearmotor given to me by a guy at work. I dont have the specs, but it's small enough to fit on a sheet of stainless right next to the mill. It's a right angle gearmotor, so the space is smaller. The whole assembly, including the switch and hopper can hang on a nail in the garage, and just sits on top of a bucket when I want to use it.

Other than the mill doesn't always grab grain, it works fine. Probably slower than most, but I can fill the hopper and come back in a few minutes and refill. That hopper holds 6 lbs of grain. I should have our Wire EDM guy on second shift cut me a pair of gears to get the idle roller always moving.

Homercidal, I'd really like to see some pics!
 
Catt22, I've been wondering about this... I've heard that somewhere in the neighborhood of 200 rpm is ideal. My current design would put me at 172. Do you think there is an advantage to going even slower than this? Personally, I'm not interested in speed when it comes to milling, just reliability. Would less than 172 result in a better crush with less dust?

I agree that 200 is probably about ideal. The 172 would also be near perfect IMO. I see no advantage in going slower than that. The dust will be minimal even at 200 and especially so if you condition the malt prior to milling, which is what I always do. There will be a difference in the crush with different mill speeds, but that can easily be compensated for through gap adjustment. It would require a substantial jump in the rpms to make a noticeable difference in the crush, but you could tell if you ran a mill at say 100 vs 600 with the same gap. The higher speed will produce a finer crush. I'm not exactly sure why this happens, but I got that information directly from a guy who once designed malt mills and he did some actual sieve analysis testing on the grist produced at various speeds specifically to see what effect the speed changes would have.
 
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