3 Roller Mega Mill Build

[maxspencer]

I was looking for a new project and needed a mill. I like the monster mills, but never really liked the friction drive and the non adjustable first crush. So, I designed my own and picked up some scrap stainless from my neighbors workshop.

-80mm diameter, 150mm length rollers
-All sealed ball bearing joints (no bushings)
-20mm axle diameters, 30mm drive shaft diameter
-17-4 and 316 SST roller and eccentric adjuster material
-6063 aluminum side plates
-5% spiral, modified simon profile fluting, 12 flutes per inch
-Fully adjustable first and second crushes (.4-1.8mm)
-All gear driven rollers

Most pics are before I added the fluting to one roller. Still need to flute the others. Also still need to complete the hopper, input shaft details and select a drive motor/gearbox. Weighs in at 27lbs right now as shown.

 

[dthompson79]

I guess this is the advantage to having the skill and access to proper tools to machine your own parts. Helluva good looking crusher so far

 

[maxspencer]

Yes, it is a ton of time investment however. A couple videos. One showing it running, a second when cutting the flutes.



[ame="http://www.youtube.com/watch?v=opn-smdR42c"][YOUTUBE]opn-smdR42c[/YOUTUBE][/ame]

 

[BeardedBrews]

So... now that you've figured out the tooling, when are you going to start selling them?

 

[tracyk]

Holy Crap Batman, thats nice!!!!!

 

[day_trippr]

That is hella impressive.
This picture made me laugh, reminded me of a Mad Magazine bit about Impossible Machines...

Closer inspection revealed some interesting offsets going on...

Cheers!

 

[RevKev]

Wow. Nicely done

 

[schematix]

i love overkill. this is beautiful! hope it works as great as it looks.

 

[scaryeyes]

Really nice work there!
But to be killjoy, I realized that bigger is not faster. I built one 2-roller mill with 60 mm rollers and 150 in length. I have yet not found any drive wheels that fit, so only driven on one roll. I found the crushing is easier with smaller rollers.
BUT! Larger diameter CAN be better! When crushing at max gap, the cernals may stay together and just get opened. This makes a huge improvement on lautering. Stuck mash be gone forever!
I drive my mill at at least 700 rpm with a drilling machine, when I havent had the time yet to complete it with a motor. But works like a charm!
Bigger rollers, much more torque needed. Just a tip on the way.

 

[maierhof]

Holy Snitzengruben!
What a build... wow.

Nice job man, nice job....
Very jealous of your machine - is that your shop or your home?

 

[The_Goldfish]

AND... I'm speechless :rockin:

 

[maxspencer]

Holy Snitzengruben!
What a build... wow.

Nice job man, nice job....
Very jealous of your machine - is that your shop or your home?

Thanks. It's the shop from my employer. Older equipment but very capable if you have the patience and determination to set it up.

 

[maierhof]

lol - nice... gotta love it
Another example of Patience and Determination at work.
Wanna make me one? lol jk (already bot a 3roller from MM then returned it for a 2 roller helix)

 

[Weezy]

 

[maxspencer]

Really nice work there!
But to be killjoy, I realized that bigger is not faster. I built one 2-roller mill with 60 mm rollers and 150 in length. I have yet not found any drive wheels that fit, so only driven on one roll. I found the crushing is easier with smaller rollers.
BUT! Larger diameter CAN be better! When crushing at max gap, the cernals may stay together and just get opened. This makes a huge improvement on lautering. Stuck mash be gone forever!
I drive my mill at at least 700 rpm with a drilling machine, when I havent had the time yet to complete it with a motor. But works like a charm!
Bigger rollers, much more torque needed. Just a tip on the way.

Seems to be crushing fine on first brew. ~80% efficiency. Also started to condition my malt too, so maybe that changes things. I'm not too worried about the ease of crushing. Its up and running now. Still need to motorize it too, but for now i just manually ran it for the last batch. I think you need to design in the drive wheels/gears before you make it. The spacing is important. I have no intention to drive it at 700 rpm. Planning on 55 rpm using a right angle gearbox. It does take a lot of torque when fully loaded with wheat...i measured about 30 ft-lbs peak. Need to turn down my drive axle to 25mm diameter and add a keyway to fit into the gearbox.

 

[Weezy]

how does the gap adjustments work with the gears, or are the changes so small it doesn't matter to the gears?

 

[maxspencer]

how does the gap adjustments work with the gears, or are the changes so small it doesn't matter to the gears?

Gap adjustment is simple, the bearing holder has an eccentric bore with bearing that the rollers ride in. Take out the bolt and rotate to the next hole that adjusts the gap. Right not it is not possible to adjust the gap on the gear side without removing the gears as there is not enough clearance to remove the bolt. I am thinking to simply cut a hole at the correct radius through the gear face so I can put a hex wrench through to remove/access the bolt. That way I can adjust gap without removing anything

The gears are 2 mod 80mm pitch diameter, i designed it so that at minimum gap the gears are running at 80mm center to center. At maximum gap they are at about 81.8mm. With the 2 mod tooth size, at the speed and torque they are running it is not a problem. For reference, the pictures i posted are with maximum gap on the primary and almost minimum gap on the secondary.

Some effort required to mount the gears to the shaft and provide the clearance. They come from eBay already with a center hole, but not the right diameter. I cut down the thickness of two of the gear faces from 20mm to 9mm. You need to be careful here cutting thru the hardened teeth. Then, I made a fixture to hold the gear true on the OD of the teeth while indicating on the gear faces. Finally, I put a self releasing taper (https://en.wikipedia.org/wiki/Machine_taper) for the bore. This bore mates with a custom collet/nut to mount to the roller shafts...DIY keyless coupling.

 

[maxspencer]

All finished with hopper, grain shutoff valve and initially just mounted to a board. Second brew with 80+ efficiency so far. Here is with 25 lbs of grain sitting in the hopper.

Next steps just to integrate it into the table top with a motor/gearbox.

 

[PsychoBiter]

What's that hopper made from or did you built that from scratch too?

 

[RevKev]

what's that hopper made from or did you built that from scratch too?

+1

 

[day_trippr]

Obviously turned from a solid block of LDPE. Duh.

 

[maxspencer]

What's that hopper made from or did you built that from scratch too?

Its actually a plastic lampshade I found in the as-is/clearance section of Ikea. I think it is this http://www.ikea.com/us/en/catalog/products/40128780/. Inside the lampshade I turned down a 6" piece of delrin into a funnel for a 2" diameter hole that feeds through the gate valve then into the top of the mill.

 

[Soulshine2]

That is hella impressive.
This picture made me laugh, reminded me of a Mad Magazine bit about Impossible Machines...

Closer inspection revealed some interesting offsets going on...

Cheers!

Me too. I saw the 3 gears meshed and thought to myself...that ain't going to work.

 

[grainwulf]

Ikea lampshade, comes in two sizes (Ikea US) and is very popular in Germany as a hopper. Since my place is half a mile away from the next Ikea-shop, I get a lot of brewing stuff from there

Best, Ruthard