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How to calculate efficiency? Why is mine so low!

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Great info Owly, yes I agree the crush needs to be improved greatly. I'm just confused by this LHBS the guy has been amazing helping me get set up, and claims (and he does a lot of buisness) that his crush is good, and guys are getting good efficiency. If everyone was as low as me I'm sure there would be more complaints. I'm heading over tomorrow to discuss this with him.

Maybe take the photo of your crushed grains, as maybe someone (a customer) messed with the mill and your crush is not typical.

The crush in your photo is an absolutely terrible crush. The mill gap in brew stores is usually .039-.040 and generally gives an efficiency of 68-70% for most people. That's tight enough for decent efficiency, but not so tight that people are complaining of stuck mashes and sparges. Your photo has grain that is mostly uncrushed with a few that are crushed.
 
I feel your pain...when I first started AG I had horrible mash efficiency 60%. After 4-5 brews I started to get it dialed in, grain crush was the most important factor. Then mash/sparge temps/times and tons of stirring (till your arm hurts). Finally water chemistry and ph levels. By the time I got it all dialed in I was hitting 75% mash efficiency, occasionally hitting 80%.

It was a personal vendetta to get my efficiency up. Bought a grain mill. Started doing 90 min mashes, batch sparging with 190deg water. Had a water report done and my tap water was awful, so started using RO water and following the water chemistry primer. Then bought a PH meter.

I tried batch sparging and fly sparging, I had better luck with batch sparging.

Then I got tired of cleaning my 3 vessel system and switched to BIAB, (hit 78%-80% routinely) and haven't looked back since.
 
I've just recently overcame low efficiency. Ended up being the crush. All systems being different it will take time to dial in your settings (temps, crush, ph) but worth the journey... most of the time. :mug:
 
I found crush was my problem when starting out, that and also realising i was messing my volumes up, also PH was a factor.
I kept calculating my batch size as 23 litres, but what a didnt realise for some time was that, that was the volume going into the fermenter and not the volume in the kettle post boil.
I have a 3 ltr dead space in the kettle so realised my batch size was actually 26litres meaning my efficiency was what was predicted.
I do no sparge full volume mash and always hit 72%
 
ImageUploadedByHome Brew1413409420.906636.jpgImageUploadedByHome Brew1413409435.707689.jpg

So I went to the brew store today, talked with my guy, he's willing to adjust the mill to whatever I like. We ran the Pilsen and specialties through his normal setting of 0.45mm which he said was just below the factory setting of 0.50 that the mill came set on. He said much tighter than 0.45 and he has trouble getting the grains to go through. I looked at the crush and it looked much better than before, he didn't recommend running it through a second time. I did run the wheat through a second time through, and there were no whole kernels left. I've calculated my water for a 6.0 gallon boil at 1.2L/lb. 90 min mash. I'm hoping it turns out! I'll post the SG readings soon!
 
That's still not a great crush- it's better, but not great.

It's hard to believe that noone else complains at .045"! My barley crusher came with a default of .039", but most people go tighter.

here's a picture I found on the 'net of a good crush:
crushed-barley.jpg


Mine is a bit more crushed than that, but I didn't think to take a photo today when I brewed.
 
View attachment 229675View attachment 229676

So I went to the brew store today, talked with my guy, he's willing to adjust the mill to whatever I like. We ran the Pilsen and specialties through his normal setting of 0.45mm which he said was just below the factory setting of 0.50 that the mill came set on. He said much tighter than 0.45 and he has trouble getting the grains to go through. I looked at the crush and it looked much better than before, he didn't recommend running it through a second time. I did run the wheat through a second time through, and there were no whole kernels left. I've calculated my water for a 6.0 gallon boil at 1.2L/lb. 90 min mash. I'm hoping it turns out! I'll post the SG readings soon!

I would not consider this an adequate crush...... The song and dance about not being able to make it feed is utter nonsense........unless it has smooth rolls, which seems highly improbable. Mine feeds at any setting I've tried down to .010........but it takes more torque at the really close settings than the set screw on the handle will pull, so I double crush.... once at a more or less normal crush in the .030 range, and once at my ultra fine crush...... If I'm doing that. Finer than you want to go with a conventional mash tun setup. I do BIAB,and a fine crush isn't an issue except for a bit more trub. Efficiency with a fine crush is tremendous, but the small loss of volume due to trub cancels out that efficiency. I often exceed 90%, but I lose half a bottle of beer, or about 7%. I still get the same number of bottles, I just don't have that half a glass of left over when I rack to bottles. For me it isn't a matter of efficiency........ I pay 50 cents a pound for grain, it's a matter of time. A 20-30 minute mash instead of a 60 minute mash. I'm honing in on a brew day that is under 2 hours start to finish. My heat and chill times are trivial now due to modifications in my process..... a 30 minute mash and a 45 minute boil, fast heat and fast chill, minimal equipment, etc, has put me consistently under 2 hours without compromising quality........... cutting my brew day to less than 50% of where I started. This matters to me as I brew once a week... That's a savings of over 100 hours a year,

H.W.
 
That's still not a great crush- it's better, but not great.

It's hard to believe that noone else complains at .045"! My barley crusher came with a default of .039", but most people go tighter.

here's a picture I found on the 'net of a good crush:
crushed-barley.jpg


Mine is a bit more crushed than that, but I didn't think to take a photo today when I brewed.

I also use a barley crusher. I started at the factory setting of .039 and decreased crush after each brew day until I had good efficiency. I ended my gap at .031.

ps; don't forget to dough in super good and stir a lot during sparging if you batch sparge. That was my final process adjustment and now I am getting 75%+ efficiency.
 
Well I'm quite pleased this go around.

6 lbs Pilsen
3 lbs wheat
1 lb caramels

3 lbs flaked wheat

For 10 lbs of fermentables I got 2.2 gal @ 1.084 first runnings, stirred the hell outa it and batch sparged 3 .5 gallons in 10 min @ 1.034. Pre-Boil was 1.050 right where the recipe said.

So it's getting better. I agree with the other posters, still could be a finer crush. I'm gonna ask him to dial it down for me on the next batch. The LHBS is very helpful, they say they'll crush however I want it.
 
However you want, just not any lower than .045 or the grains won't go through, and worried for some reason (?) about running through twice....haha...still a bit puzzled with this LHBS. Glad to see numbers are up, sure you can do better (if you're interested in it).
 
Your LHBS is taking the p*ss - that first crush pic you posted is just plain terrible. Agreed its looking better though.

Like you I went through all this too - here's the thread https://www.homebrewtalk.com/f39/why-my-efficiency-so-low-472572/

To summarize I was stuffing up 3 things.
1. Grain crush was rubbish
2. Was fly sparging too fast
3. Sparge water was not hot enough

After adjusting those 3 things my low efficiency problem went away.

Btw as a result I got myself a MM2 mill. It's set to 0.45. I can go tighter on the gap but I'm happy with the crush for now.
 
I was playing on the cautious side with this last batch. The next batch I'll be switching to a fly sparging system, and I'm also going to send all the grains throughout twice at the 0.45mm setting. I'm learning a lot with each go, and thanks to he advice here from the forum, I'm documenting everything well, and avoiding lost of other easy beginner mistakes. Thanks again for your help!
 
Folks - just keep in mind units here - and this is where I have to really question what the LHBS is telling OP about what their mill is set at (or OP's interpretation thereof):

They say it's set at .45mm - are you positive it's .45mm, and not .045" (inches)? Seems weird that a place in Ohio would be using metric, but not completely unbelievable... Anyway, if they are really using metric, and it's truly 0.45mm, that converts to roughly .018". I routinely set my mill to about .035", and I know I get a finer crush than what has been pictured so far by OP.

If it's .045", that would jive with the pictures, and the LHBS is talking out their hindquarters when saying that they can't run their grain through if they close the gap any further (well, unless it's a really slapdash mill, I guess).

If they're indeed telling you .45mm though, then they're flat out lying about what they're set to. I would believe that they wouldn't want to go smaller than a .45mm gap - but they're no where near that gap with the crush they're giving you.
 
Stratslinger

Excellent info, and I will investigate, I'm a little taken aback at how folks think the LHBS guy is lying or crazy, you all must have had some really terrible experiences in the past. I think it's much more likely, that a newbie brewer, is not accurately conveying information in this "telephone" style game. He's a good guy, and offers great service, and is equally interested in solving my effiecency woes.
 
Stratslinger

Excellent info, and I will investigate, I'm a little taken aback at how folks think the LHBS guy is lying or crazy, you all must have had some really terrible experiences in the past. I think it's much more likely, that a newbie brewer, is not accurately conveying information in this "telephone" style game. He's a good guy, and offers great service, and is equally interested in solving my effiecency woes.

Pictures don't lie, and it's pretty unusual if a mill cant go lower than .045.
 
ImageUploadedByHome Brew1413750898.352860.jpgImageUploadedByHome Brew1413750910.001757.jpg

So enjoyed a lovely Sunday with fall colors, and a little time off from work today. Was not planning on brewing, all fermenters are full, though wanted to goto the LHBS and fiddle with the mill, and see what kind of results I can get.

The first picture is running some 2-row through at 0.45mm (checked and it is in mm on this mill) twice over. It gave a good crush, better than what I last posted in my opinion, though still not what other posters have put up.

So I asked the LHBS to set the mill at 0.39mm for a tighter crush. We set the mill put in the grain and started running it through. Guess what, it didn't go through!!! You could spin the mill all day long, and not a kernel would go through. Then the HBS suggested running it through at 0.45, then reset the mill and run it through at 0.39. Worked brilliantly! That's the second picture and to me looks just about right. All endosperm are out of the shell and crushed/cracked thoroughly, and the shells are intact 3/4 of the way to set up a nice filter during sparge.

I'm gonna do some tests with both to check grain bed set up and efficiency. I'm concluding that this mill is similar to others, and that you can't mill beginning at 0.39 or less, but have to start with a larger gap and then re-run at a tighter setting. If so, this is important information for a newbie to know!

Thanks again for the help!
 
View attachment 230535View attachment 230536

So enjoyed a lovely Sunday with fall colors, and a little time off from work today. Was not planning on brewing, all fermenters are full, though wanted to goto the LHBS and fiddle with the mill, and see what kind of results I can get.

The first picture is running some 2-row through at 0.45mm (checked and it is in mm on this mill) twice over. It gave a good crush, better than what I last posted in my opinion, though still not what other posters have put up.

So I asked the LHBS to set the mill at 0.39mm for a tighter crush. We set the mill put in the grain and started running it through. Guess what, it didn't go through!!! You could spin the mill all day long, and not a kernel would go through. Then the HBS suggested running it through at 0.45, then reset the mill and run it through at 0.39. Worked brilliantly! That's the second picture and to me looks just about right. All endosperm are out of the shell and crushed/cracked thoroughly, and the shells are intact 3/4 of the way to set up a nice filter during sparge.

I'm gonna do some tests with both to check grain bed set up and efficiency. I'm concluding that this mill is similar to others, and that you can't mill beginning at 0.39 or less, but have to start with a larger gap and then re-run at a tighter setting. If so, this is important information for a newbie to know!

Thanks again for the help!

Most mills, in the US anyways, are set in thousandths of an inch, hence the confusion.
 
Also, if it actually is .45mm the grain should be crushed a lot more...that's less than half .039"
 
When I did infusion mashes, I crushed around .025. Crush makes biggest difference.

Use the calculators at brewersfriend.com to calc efficiency


Sent from my iPad using Home Brew
 
I have a question regarding this topic. I never figured out my efficiency before but my last beer I hit the number on my recipe dead on and I went back into Brewers friend calculator and it said I was at 60% efficiency. Is that my recipe or am I missing something. My software is set 70%
 
Here's a neat thing. My efficiency has gone up almost five points when I got a new mash paddle. You see, i got a sweet one for my birthday. It is so much better at stirring up my wort during batch sparge that it showed up in my numbers. Love that thing.
 
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