DIY grain mill in the works...

[Huaco]

I thinking about using aluminum round stock instead of steel. You think it would hold up long term?

No... You might get a handfull of batches out of it. From what I hear, the rollers actually take quite a beating. Stainless rollers will even wear out over time.

 

[greenstar]

Sweet project thread, guys! Wish I had a mill & lathe at my disposal. I could think of at least a dozen projects I'd like to build.

 

[clintopher]

Sweet project thread, guys! Wish I had a mill & lathe at my disposal. I could think of at least a dozen projects I'd like to build.

It does come in handy.

 

[danb35]

I've been thinking of doing something like this as well. Just have a lathe, though, no mill, so I might need to get creative with some of the machining. I'll be watching this one.

 

[stamandster]

What about using round tube instead of solid bar? Something with a little thicker walls though. And does it need to be stainless? Something with a high Rc (or Brinell if you prefer) and if it's over 3" it wouldn't need to be knurled?

 

[Huaco]

Yes, the thick walled pipe like a 3" Sch. 160 would probably work, but it is adding much more work to the build by having to add an axle rod and end caps... all while making sure they are exactly centered. If not centered, you would have to turn the OD of the pipe concentric with the axle and by that point, you might as well be just turning integrated axles into a solid piece of bar.

 

[stamandster]

So more work than it's worth I guess

 

[Gixxer]

Your mill looks great! I too am making a mill, using 1/2" shafts, end caps, 1.6" steel conduit for the rollers. Also using ball bearings all the way around. 1.375 OD... For the gap adjustment I have slots milled for the whole bearing to slide, and threaded rods with set screws for adjustment. My problem is I have the easy bake oven of lathes so I could only turn 4" rollers on the shaft.

 

[jeepinjeepin]

What about using round tube instead of solid bar? Something with a little thicker walls though. And does it need to be stainless? Something with a high Rc (or Brinell if you prefer) and if it's over 3" it wouldn't need to be knurled?

I've also heard that larger rollers didn't need to be knurled but I just found some livestock feed mills with 11" diameter rollers that they can re-knurl 5 times for wear. They are roller mills just like we use for brewing just a lot bigger. Are they knurled to increase feed rate?

Yes, the thick walled pipe like a 3" Sch. 160 would probably work, but it is adding much more work to the build by having to add an axle rod and end caps... all while making sure they are exactly centered. If not centered, you would have to turn the OD of the pipe concentric with the axle and by that point, you might as well be just turning integrated axles into a solid piece of bar.

I would guess that pipe is far from perfect and would have to be turned true even if you found and installed the axle on the exact (average) centerline.

 

[Gixxer]

The pipe does have to be turned true after its mounted to the shaft, but not that time consuming

 

[Huaco]

So is it really worth that much work to use pipe over solid bar stock? I guess if you had a lathe at your disposal and you are just REALLY wanting to build a mill out of "found" materials... Maybe then it would be worth the extra time and effort.
Me... Not the case. I am trying to keep machining time down to a minimum.

 

[jeepinjeepin]

The only advantage I can see using pipe over bar is in larger sizes where weight becomes a real concern. I need to look at roller design on commercially made mills with rollers above 4" diameter. I already have a mill and I don't have the access to tools to make rollers or side plates. I'm just curious.

 

[Huaco]

The only advantage I can see using pipe over bar is in larger sizes where weight becomes a real concern. I need to look at roller design on commercially made mills with rollers above 4" diameter. I already have a mill and I don't have the access to tools to make rollers or side plates. I'm just curious.

Good point... It would be much better if you were going to use 4" plus rollers to use thick walled pipe. However, I have heard of guys that have used pipe or conduit get the rollers all dinged up from that occasional REALLY hard grain or small stray rock.

 

[Gixxer]

So is it really worth that much work to use pipe over solid bar stock? I guess if you had a lathe at your disposal and you are just REALLY wanting to build a mill out of "found" materials... Maybe then it would be worth the extra time and effort.
Me... Not the case. I am trying to keep machining time down to a minimum.

Yup. I have a lathe and my time is not as expensive as purchasing a mill. So far I am 30 bucks in on this project. But honestly if I had the money I would for sure get a 3 roller mill with hardened rollers and be done with it.

 

[clintopher]

I've been thinking of doing something like this as well. Just have a lathe, though, no mill, so I might need to get creative with some of the machining. I'll be watching this one.

You don't need a milling machine...I just used the one at the shop to drill holes in the side plates and to steady the tap while I got it started. I also faced the ends of the side plates with an end mill but that's not absolutely necessary. Do you have a drill press with a vice?

 

[clintopher]

What about using round tube instead of solid bar? Something with a little thicker walls though. And does it need to be stainless? Something with a high Rc (or Brinell if you prefer) and if it's over 3" it wouldn't need to be knurled?

I was originally going to use 4" pipe. Plan was to weld plates on the ends, drill holes in the plates, weld an axle in place through the holes, and true the pipe up in the lathe. I never got around to it. Then the round stock and the knurling tool popped up at the shop and I jumped on it.

 

[danb35]

You don't need a milling machine...I just used the one at the shop to drill holes in the side plates and to steady the tap while I got it started. I also faced the ends of the side plates with an end mill but that's not absolutely necessary. Do you have a drill press with a vice?

I do have a drill press and vise, and for that matter an X-Y vise I could mount on the drill press. I also just got a 4-jaw chuck for the lathe, which should help out--I'm figuring I could drill/bore more precisely that way than on the drill press. I'm more a woodworker than a machinist, though, so still getting the feel for the lathe (and using the drill press in metalworking).

 

[clintopher]

I do have a drill press and vise, and for that matter an X-Y vise I could mount on the drill press. I also just got a 4-jaw chuck for the lathe, which should help out--I'm figuring I could drill/bore more precisely that way than on the drill press. I'm more a woodworker than a machinist, though, so still getting the feel for the lathe (and using the drill press in metalworking).

Definitely mount the xy vice in your drill press. That'll make life with the plates a cake walk. On the lathe, go slow with the knurling tool. I'm definitely no expert but I set the machine up for 135 rpm and pumped a cooling lubricant on the stock as it was rotating. I don't know if that was necessary or not but most of the youtube videos of knurling showed using some sort of oil.

We have a four jaw in the shop too but it's not installed. I would rather have used it to offset the hole in the adjustment knobs more. Our 6 jaw has
.030" of adjustment and I would have like more but not enough to change the chucks out.

 

[stamandster]

Wish I had a lathe! I have the drill press though. Still, looking forward to the final product!

 

[clintopher]

Almost finished. Just need to trim the plate the hopper sits on to final dimension and see if this thing actually works. Here's a pic of it looking into the hopper/rollers.

 

[Huaco]

Very nice man! I like the use of the reflector as a hopper! Any idea how much it will hold?

 

[Gixxer]

Looks good so far!

 

[jeepinjeepin]

Very nice man! I like the use of the reflector as a hopper! Any idea how much it will hold?

Those things aren't exactly small. If guess 20 pounds at a minimum, maybe 30 or more.

 

[clintopher]

The rim of it is bigger in diameter than my 44 qt Bayou Classic by a few inches. I'm with jeepin...better than 30 lbs is my guess. It's a little silly how big it is, but I didn't have to put anything together.

 

[stamandster]

You could also use a stainless bowl from somewhere like Job Lot or Big Lots (cheapo, like 5-8 bucks) they sell really large ones. Not sure about depth though.

 

[alexnharvey]

Could I use caster wheels inside pipe to create rollers?

 

[Huaco]

^^^^^^^
Don't see why not. You would need to machine the two to be a press fit. Also, probably best to use solid wheels, not spoked wheels.

 

[alexnharvey]

I was thinking that if I used plastic wheels the machining would be quite easy.