Grain Crusher Roller Issue

[flbrewer1]

Noticed this morning (cleaning out my mash tun) that there was a small amount of metallic flecks at the bottom of the tun. After checking a few things and ruling them out, I ran a pound of grain through the Barley Crusher again.

Ran a rare earth magnet through it and knew the problem right away. For whatever reason small flecks of metal are coming off my mill. I've run about 80-100 pounds of grain through this mill.

My immediate question is if this is harmful? I don't think much made it to the boil and I've never seen this in the final product. I certainly don't want to dump this 5 gallon batch.

Secondly, is this a common occurrence?

 

[Bobby_M]

I've had a couple customers actually bind up a pair of chugger pumps due to accumulation of metal dust in the heads and we eventually traced it back to the mill also. You can monitor any metal contamination by taping a rare earth magnet to the outside of your hose off the MLT or attach it to a stick and stir your milled grist up with it. It seems like some mills are worse than others.

 

[flbrewer1]

I've had a couple customers actually bind up a pair of chugger pumps due to accumulation of metal dust in the heads and we eventually traced it back to the mill also. You can monitor any metal contamination by taping a rare earth magnet to the outside of your hose off the MLT or attach it to a stick and stir your milled grist up with it. It seems like some mills are worse than others.

Good to know at least one other person has had this issue! I think it's more common but people don't catch it like I did today.

 

[Qhrumphf]

I would assume that it's not going to be anything harmful, or at least nothing harmful would make it through to the finished beer. I would assume whatever makes it out of the mill would primarily get bound up in the mash tun, whatever makes it out of the mash tun would drop out in the kettle, and whatever happens to make it out of the kettle would drop out in the fermenter.

You could try checking bottles or keg lines or something to see if anything happens to make it to the final product. I'd be surprised.

Interesting though. I've never noticed it, but my issues with my Barley Crusher today (passive roller decided to seize on me mid crush), it's fresh in my mind now. I'll be keeping an eye out for it.

 

[flbrewer1]

I would assume that it's not going to be anything harmful, or at least nothing harmful would make it through to the finished beer. I would assume whatever makes it out of the mill would primarily get bound up in the mash tun, whatever makes it out of the mash tun would drop out in the kettle, and whatever happens to make it out of the kettle would drop out in the fermenter.

You could try checking bottles or keg lines or something to see if anything happens to make it to the final product. I'd be surprised.

Interesting though. I've never noticed it, but my issues with my Barley Crusher today (passive roller decided to seize on me mid crush), it's fresh in my mind now. I'll be keeping an eye out for it.

I agree with you. Considering there was quite a bit at the bottom of the mash below the false bottom leads me to believe it dropped down there and didn't get transferred over. Based on some advice from someone, I've gone the extra OCD mile and taped some rare earth magnets around the fermenter to see if anything is picked up.

I'm assuming it's happened before and I've never seen any foreign objects in my beer (thanks to kegging and Whirfloc). I'm certainly going to hold off on any future crushes with this one until I hear back from BC.

 

[bja]

Is it steel or aluminum? I would guess aluminum, but either way, it's not going to hurt you.

If you take a good look at the mill, you should be able to see where it's coming from.

 

[Cider123]

I have gotten flecks off my BC, but not from the rollers. For me it was where the chuck of my electric drill attached to the rod from the side of the mill. If the chuck slipped, and often did, the drill would shear off some metal. I guess some could get in the milled gran but usually it was on the outside. The flat groove cut in that rod where you would attach a drill or the crank handle could be a bit larger.

 

[flbrewer1]

Is it steel or aluminum? I would guess aluminum, but either way, it's not going to hurt you.

If you take a good look at the mill, you should be able to see where it's coming from.

The rollers are steel. Everything else on it is aluminum and wouldn't react with the magnet. I'm going to take a closer look today.

 

[flbrewer1]

I have gotten flecks off my BC, but not from the rollers. For me it was where the chuck of my electric drill attached to the rod from the side of the mill. If the chuck slipped, and often did, the drill would shear off some metal. I guess some could get in the milled gran but usually it was on the outside. The flat groove cut in that rod where you would attach a drill or the crank handle could be a bit larger.

Makes sense, but I hand crank and like you said, that wouldn't make it into the bucket.

 

[flbrewer1]

Upon furthering inspection, I did get some additional flecks picked up from the rollers. Also, when I pulled the mill off the mill base, I saw a lot of metal flecks there. I'm not sure where these are coming from as they in a strange spot.

 

[day_trippr]

The simplest answer is they're from the mill roller knurling.
Either left over from original machining, or jagged bits getting knocked off by grain.
What's under the mill could be from Day 1, or yesterday.

How many pounds have actually been run through this mill?

Cheers!

 

[flbrewer1]

Around 80-100 pounds.

 

[day_trippr]

If the metal bits had accumulated near the bearings I'd say you had an actual problem. But scattered along the roller width I'm inclined to believe you just had a rougher-than-maybe-typical roller or two that took longer to clean up that usual.

In any case, there are lots of places for iron bits to fall out of the beer before making it all the way to a bottle or glass. I guess I'd be extra careful when racking/transferring the beer, and keep an eye on things going forward to see if the metal shedding abates...

Cheers!

 

[helterscelter]

If the metal bits had accumulated near the bearings I'd say you had an actual problem. But scattered along the roller width I'm inclined to believe you just had a rougher-than-maybe-typical roller or two that took longer to clean up that usual.

In any case, there are lots of places for iron bits to fall out of the beer before making it all the way to a bottle or glass. I guess I'd be extra careful when racking/transferring the beer, and keep an eye on things going forward to see if the metal shedding abates...

Cheers!

Could always put a rare earth magnet against the outside or under of your fermenter after pitching, that should capture most all of the metal shavings in the bottom/trub. Just be careful about disturbing while racking.

Edit: assuming there metal flakes are ferrous anyway.

 

[outside92129]

When i first got my mm3 it was covered in lots of metal flakes left over from the knurling process. I took out the rollers to scrub them down (also to get rid of the machining oil) and it's been good ever since. I'm guessing you're having the same issue. The flakes won't hurt or have any effect on the beer, but Bobby_M raises a good point about the pumps. I'd clean the rollers just in case. Should be a one time thing.