I recently found that there was a home brew store much closer to my house than the one that I had been visiting. The new store has a larger selection of grains, yeast, and hops; but I've been having a lot of trouble with slow or stuck mashes since I started going to the new store.

I don't have my own mill, so I rely on the LHBS to mill my grains. I thought that the mill at the new store might be too tight, but they assured me that opening it up any more would cause a lot of the grain to fall through totally un-cracked.

My current setup is a 5 gallon round igloo cooler with a false bottom. I'm generally mashing at 154° F for about an hour. If I fill my mash tun with only water if flows freely.

I've now had two batches that we so stuck that I had to abandon them, even straining through a colander wouldn't work.

  • What would you recommend I do?
  • Is there some way I can verify that their mill is set properly?
  • Should I be using a bazooka tube instead of a false bottom? A grain bag?
  • More rice hulls?
  • My own mill?
  • 1
    Probably not an option if you're crushing grain at the LHBS, but I've found grain conditioning lets me grind very fine but leave the hulls mostly intact. Oct 3, 2012 at 22:19
  • Quick update: I was able to open up their mill a little, the crush looks a lot closer to what I was getting at the other LHBS -- I also spoke to them about grain conditioning and they are ok with me bringing a spray bottle and using their mill.
    – jessecurry
    Oct 11, 2012 at 16:36

3 Answers 3


It sounds like it's the crush. Get some feeler gauges and measure the distance. Typical distance is 0.038 to 0.042 inches.

enter image description here

  • I heading over there today to get some kegging equipment. I'll see if I can get a set of feeler gauges before I go.
    – jessecurry
    Oct 4, 2012 at 16:00

To really verify their crush, you'd need some kind of sizing screen. For a quick check, though, I'd just dump a cup of milled grain into a sandwich bag and shake it a bit. You should be able to see how much flour or really fine particles are in there. If you've got a lot of small stuff, then their mill is too tightly gapped. Doesn't sound like they're willing to adjust it, though, so you may have to resort to buying your own mill. Apparently there's a good one out for about $100, maybe it'd be worth looking into.

  • Any idea why they might want to have their mill so tightly gapped? I don't think that efficiency would increase much.
    – jessecurry
    Oct 4, 2012 at 15:58
  • I have heard that it makes conversion go faster, but I don't really know. Maybe they're catering to the BIAB crowd?
    – TMN
    Oct 4, 2012 at 16:39
  • They do seem to sell a lot of the bags there.
    – jessecurry
    Oct 4, 2012 at 21:48

It might be their mill, or it might be that your system isn't capable of dealing with properly milled grain. What kind of efficiency were you getting from the other shop that milled your grain? If it was good, then I'd say the mill at the new shop may be set too fine. If you were getting low efficiency before, you might want to consider changing your lautering system. I use a SS braid and I've found it to be much less prone to stuck runoffs than either a false bottom or manifold.

  • Efficiency has been about the same from both places. It seems that most of the people that frequent the new store dislike false bottoms, I wonder if it is due to the mill.
    – jessecurry
    Oct 3, 2012 at 19:50
  • Boy, if your efficiency is about the same it makes me doubt that crush is the real problem. Have you brewed the same recipe with grain from each place?
    – Denny Conn
    Oct 4, 2012 at 16:08
  • I haven't done the same recipe with grain from each place. There could be some error in my efficiency calculations.
    – jessecurry
    Oct 4, 2012 at 16:15

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.