Grain Mill - Hopper Design

[Benniee]

I've just had a monster mill arrive at my doorstep - and now need to mount it and make up a hopper.

I'm relatively handy with the tools so I'm not too concerned - but I'm wondering what size openning at the base should I aim for?

I'm guessing that I should go no wider than the center line of each roller - but is it a good idea to narrow this in a bit?

I plan on sloping 2 sides only.

Benniee

 

[Hutch]

Hey benniee,

Got one of these myself (MM2), and initially had too narrow a slit delivering into the rollers (about 3mm) thinking this was necssary to prevent the rollers from stalling (I thought I had read that advice somewhere on here). The thing just ran too slowly, and often grain just completely stopped flowing into the rollers. I've since widened it to about 15mm, with each chute almost touching each roller, and it works brilliantly. I think you could happily get away with a much wider gap (as I've seen on other hoppers), though I reckon you want to make sure the chutes are almost touching the rollers, to avoid any grain escaping (in case you need to reverse the direction of the rollers when it stalls).

If I remember to take photo's, I'll post them here.
hutch.

 

[Tony]

to the center of each roller will work fine mate

I figured if the grain cant fall out of a gap anywhere, it doesnt really matter so i went with a nice wide gap to facilitate a fast reliable feed of grain to the rollers.

I didnt want to narrow a gap and risk the grain hanging up in the hopper
works a treat

cheers

PS...... that hopper holds 15kg of grain, as you saw

 

[Benniee]

Got one of these myself (MM2), and initially had too narrow a slit delivering into the rollers (about 3mm) thinking this was necssary to prevent the rollers from stalling (I thought I had read that advice somewhere on here). The thing just ran too slowly, and often grain just completely stopped flowing into the rollers. I've since widened it to about 15mm, with each chute almost touching each roller, and it works brilliantly. I think you could happily get away with a much wider gap (as I've seen on other hoppers), though I reckon you want to make sure the chutes are almost touching the rollers, to avoid any grain escaping (in case you need to reverse the direction of the rollers when it stalls).

Thanks Hutch - that's just the sort of info I was looking for. Would love to see some photos if you get a chance.

I've been scouring AHB and the internet in general looking for good design elements to include in my hopper and mount.

Benniee

 

[Benniee]

to the center of each roller will work fine mate

I figured if the grain cant fall out of a gap anywhere, it doesnt really matter so i went with a nice wide gap to facilitate a fast reliable feed of grain to the rollers.

I didnt want to narrow a gap and risk the grain hanging up in the hopper
works a treat

cheers

PS...... that hopper holds 15kg of grain, as you saw

Thanks for the pics Tony - your whole setup is a beauty alright

The more I read the more I see that Hutch is on the money in that the distance from the surface of the rollers is more important than the opening size.

Benniee

 

[Cortez The Killer]

Here are some piccies of mine http://hyperfox.info/webalbum03/index.html

I originally made a hopper like Tony's - but poor design techniques on my behalf led to a lot of escaping grain

The picture design I borrowed from Screwtop works very well and is very easy to construct

Cheers

 

[Benniee]

Here are some piccies of mine http://hyperfox.info/webalbum03/index.html

I take it the lage chunk of pine is just to anchor the cooler bottle. How do you dump the grain from that block of pine to the mill? Just with a hole the same diameter as the bottle?

Benniee

 

[Cortez The Killer]

I take it the lage chunk of pine is just to anchor the cooler bottle. How do you dump the grain from that block of pine to the mill? Just with a hole the same diameter as the bottle?

It's a little slow here today - so here's a diagram of the top part of my mill - best I could do with MS Paint

The bottle lip rests on the bottom panel

I cut out the hole in the pine and hand sanded it until the bottle fit in nice and snug - it's very secure

From memory I'd say the slot is 20mm wide

Construction is very easy - though you will need another 4 bolts to secure the base plate at the bottom of the mill (if you go that way) - I had some on hand

Cheers

 

[Cortez The Killer]

Also with respect to the slot width

I'd probably have closed mine a bit further with hindsight as quite a bit of torque is required to drive the mill (I also run it pretty fine )

You can always open it up if it's feeding too slow

Cheers

 

[Hutch]

Thanks Hutch - that's just the sort of info I was looking for. Would love to see some photos if you get a chance.
Benniee

Benniee, a couple of photos showing you what I did.

Inside the hopper, I used thin aluminium sheet (from Bunnings) to form the two sloped sides of the delivery chute. They are both curved downwards near the centre, delivering the grain into the rollers, and almost touching the rollers as well. The gap is about 15mm. The Al sheet is soft enough to bend quite easily by hand, but needed to be fixed in place with some MDF (underneath)...


The next few pics show the hopper underside, and how it mounts on top of a 20Ltr pail. Mine had to be easily stored inside my cylindrical mash-tun (I store my stuff out in the rain), which was an annoying design limitation :angry:
There are numerous screws under the base to hold it rigidly in place on the pail. The hopper is tall and rectangular (instead of "conical" shaped) due to the storage limitation. If I was not limited in this way, I would have preferred a conical shape (as most others have done) as it is much simpler in design, easier to build, and holds more grain!!! FWIW, it holds just over 6kg grain.



Hope this info helps you in some way.
Cheers, Hutch.

 

[yardy]

Nice job Hutch B)

 

[geoff_tewierik]

You've done a great job there Hutch, and given me an extra idea to incorporate into my own design.

Cheers,

GT