Malt: Skagit Valley Pilot Pilsner; Assortment: 94-4-1; 4.4% moisture

Mill: Monster Mill 3 Roller, 1.5" roller; 1/3 hp @ 175 rpm

Gap (1/1000 in) #14 #30 #60 pan

45 70% 16% 6% 8%

35 61% 23% 8% 8%

30 52% 30% 9% 10%

25 42% 36% 10% 12%

- Thread starter eldplanko
- Start date

Malt: Skagit Valley Pilot Pilsner; Assortment: 94-4-1; 4.4% moisture

Mill: Monster Mill 3 Roller, 1.5" roller; 1/3 hp @ 175 rpm

Gap (1/1000 in) #14 #30 #60 pan

45 70% 16% 6% 8%

35 61% 23% 8% 8%

30 52% 30% 9% 10%

25 42% 36% 10% 12%

I've got the same mill, and am interested in your analysis. However, I must admit, I'm not exactly sure how to interpret this data. Would you mind stepping me through it a bit?

- Thread Starter
- #4

By itself doesn’t mean much, as depends on your lautering system. The percentages represent a particle size distribution, above #14 is coarse, under #60 is fine. Finer grind = quicker conversion, but at the cost of potential stuck or long sparge time. Last mash I did was at 45-thousandths, got 80% conversion by 30 minutes and 96% conversion by 70 minutes, so even with a large percentage above #14 got near full conversion in about an hour. Lauter was 45 min, or about 2L/min with 89% extract into the kettle.

Next time will be 30-thousandths, targeting ~50% above #14, try to get full conversion time down, and still maintain a reasonable sparge.

Next time will be 30-thousandths, targeting ~50% above #14, try to get full conversion time down, and still maintain a reasonable sparge.

- Thread Starter
- #5

I was surprised, I think this mill can be really cranked down.Even the finest grind looks awfully coarse.

- Thread Starter
- #7

There’s only one way to find out how much you can push the system. I ran this mill forever at 45-thousandths because it was considered “safe” and was surprised how coarse it was... the main reason for sharing this info.Just watch those hulls at 175 rpm there will be quite a bit of shredding, might require some conditioning.

Ah, I think I see then...The percentages represent a particle size distribution, above #14 is coarse, under #60 is fine. Finer grind = quicker conversion, but at the cost of potential stuck or long sparge time.

At 45/1000th gap, 70% of milled grain DID NOT pass through the #14 sieve

Of the 30% that DID pass through the #14 sieve, 16% DID NOT pass through the #30 sieve

Of the 14% that DID pass through the #30 sieve, 6% DID NOT pass through the #60 sieve, and 8% DID pass through into the collection pan

Sorry for my naiveite, but trying to make sure I have this data correct.

Also, did you do a fair bit of shaking of the sieves?

- Thread Starter
- #9

You got it.... 3 min shake, side to side, tap every 15 seconds.Ah, I think I see then...

At 45/1000th gap, 70% of milled grain DID NOT pass through the #14 sieve

Of the 30% that DID pass through the #14 sieve, 16% DID NOT pass through the #30 sieve

Of the 14% that DID pass through the #30 sieve, 6% DID NOT pass through the #60 sieve, and 8% DID pass through into the collection pan

Sorry for my naiveite, but trying to make sure I have this data correct.

Also, did you do a fair bit of shaking of the sieves?

ALL of the breweries with a VERY coarse grind had good brewhouse efficiencies (89% and above).

NO breweries with finer grinds had efficiencies in the 89% or higher range."

I would not have guessed that a more course grind would increase brewhouse efficiency. Judging by the report in conjunction with your findings, the 45/1000ths (~1.1mm) gap size appears to be optimal.

Cool data. I appreciate you taking the time to do the work and post the results!