Gravel in grain?

[Dland]

I was milling for a brew this morning and my roller mill stopped, which it has a few times before if I run the drill too fast. Usually can get going again small stick like paint stirrer. This time was different, so I was cursing the thing. Decided to dump grain out and try to mix with one of the other grains in the mash, as this malt does have extra nice full kernels, and I noticed a small piece of gravel in the container I dumped in.

Now I have something else to check for when weighing out grain bill. First time I have noticed this, but would probably never have noticed with old corrona mill. Probably about 400#s though this mill, so I guess this is not a common problem. Have seen bug bits, pieces of other types of grain, straw, etc, but first time for rocks.

 

[Vale71]

Bagged malt is usually very clean but this can still happen. After all it's stuff that was picked off an open field.

 

[Qhrumphf]

Metal is the really scary one. Most commercial mill setups have powerful magnets above the mill for this reason.

I see more pebbles and twigs than I do bugs, but certainly that too. But that's more related to poor storage. Fortunately the numbers of screws, nuts, bolts, and washers I've found has been very very small. But terrifying every time. A friend had a ball bearing in one of his sacks.

 

[CodeSection]

Metal is the really scary one. Most commercial mill setups have powerful magnets above the mill for this reason.

I see more pebbles and twigs than I do bugs, but certainly that too. But that's more related to poor storage. Fortunately the numbers of screws, nuts, bolts, and washers I've found has been very very small. But terrifying every time. A friend had a ball bearing in one of his sacks.

Wow, I never heard of this until now! What is your solution to prevent metal from getting caught in the mill?

Not knowing the size of screws, nuts, bolts and washers you found, do you think 1/4" hardware screen in the hopper would have caught those items and still let the grain pass through? I wonder if strong magnets on the outside of the hopper would create enough of a magnetic field to help catch metal from inside of the hopper?

 

[Qhrumphf]

Wow, I never heard of this until now! What is your solution to prevent metal from getting caught in the mill?

Not knowing the size of screws, nuts, bolts and washers you found, do you think 1/4" hardware screen in the hopper would have caught those items and still let the grain pass through? I wonder if strong magnets on the outside of the hopper would create enough of a magnetic field to help catch metal from inside of the hopper?

Magnetic grate in the hopper itself, above the trap/rollers, or built into the side at the bottom of the hopper immediately above the trap/rollers. A screen would work too, but needs to be wide enough to let grain pass without bridging- 1/4" is gonna be too small.

When I say small numbers of metal items, I mean small numbers. I've milled hundreds of thousands of pounds of grain (I do this for a living) and I've had one washer and one bolt get caught by the magnet (and in the probably 1500-2000 lbs I've milled at home over the years, never had it happen). Mostly it's just iron dust that the magnet grabs.

The biggest risk is fire from sparks if it happens. I don't see much happening at home apart from jamming and damaging your mill. I wouldn't worry about it.

But it does happen.

 

[CodeSection]

Magnetic grate in the hopper itself, above the trap/rollers, or built into the side at the bottom of the hopper immediately above the trap/rollers. A screen would work too, but needs to be wide enough to let grain pass without bridging- 1/4" is gonna be too small.

When I say small numbers of metal items, I mean small numbers. I've milled hundreds of thousands of pounds of grain (I do this for a living) and I've had one washer and one bolt get caught by the magnet (and in the probably 1500-2000 lbs I've milled at home over the years, never had it happen). Mostly it's just iron dust that the magnet grabs.

The biggest risk is fire from sparks if it happens. I don't see much happening at home apart from jamming and damaging your mill. I wouldn't worry about it.

But it does happen.

Thanks for the info! Based upon your volume of milling, it sounds like statically I probably will never encounter any metal. With that said, it probably makes sense to spend $20 or so on magnets to protect my $389 investment in my mill. I have different sizes of hardware screen and I can easily attached magnet bars to any of them.

Again, thanks for the warning!

 

[bruce_the_loon]

If you are concerned despite the extremely low chance, get some rare earth magnets, shove them in a length of silicone tube, form it into a arc and pour the grain across it. If you keep a slowish rate, it should catch anything metallic.

 

[CodeSection]

If you are concerned despite the extremely low chance, get some rare earth magnets, shove them in a length of silicone tube, form it into a arc and pour the grain across it. If you keep a slowish rate, it should catch anything metallic.

Good idea!

 

[processhead]

If you are concerned despite the extremely low chance, get some rare earth magnets, shove them in a length of silicone tube, form it into a arc and pour the grain across it. If you keep a slowish rate, it should catch anything metallic.

Great idea, although this will only catch ferrous metals. Still, better than nothing, and many non-ferrous metals are softer w/exception of stainless steel.