I need a way to gauge what constitutes a “good crush”, so I thought I’d gauge the gap, at least at first.
But, I do know what .045" produces (i.e., a lot of intact and barely-split kernels that I have to pinch REALLY hard to open further), so I guess I can just start wide and run small handfuls through until it looks better than that.
On the flipside, how will I know it’s too narrow, other than a stuck runoff?
[quote=“ickyfoot”]I need a way to gauge what constitutes a “good crush”, so I thought I’d gauge the gap, at least at first.
But, I do know what .045" produces (i.e., a lot of intact and barely-split kernels that I have to pinch REALLY hard to open further), so I guess I can just start wide and run small handfuls through until it looks better than that.
On the flipside, how will I know it’s too narrow, other than a stuck runoff?[/quote]
That’s exactly how you know it’s too narrow. It’s also exactly what I did. I have absolutely no idea what the gap on my mill is. I just kept cranking it down til I almost got a stuck runoff (very slow runoff. It’s no big deal, don’t be afraid of it.). Then I opened it enough so that I could barely see the rollers move. that’s where it’s been for the last 12 years. And don’t think that becasue someone else uses a specific gap width is will necessarily be right for you. It depends on your system. Overall, you’re better off learning what a good crush looks like and shooting for that.
Cool sounds good. I’ll tighten it until there are no uncrushed/poorly crushed grains, or at least significantly fewer than the LHBS mill produces. Then, I’ll see how draining and efficiency go. Hopefully this weekend!
In the event that the runnings do stall out, is it just a matter of stir, vorlauf, drain, and repeat as needed until the tun’s empty?
Its too narrow if the grain won’t go through the mill.
lol, right on.
[quote=“ickyfoot”]
In the event that the runnings do stall out, is it just a matter of stir, vorlauf, drain, and repeat as needed until the tun’s empty?[/quote]
You got it! Remember, crush til you’re scared!
[quote=“ickyfoot”]
In the event that the runnings do stall out, is it just a matter of stir, vorlauf, drain, and repeat as needed until the tun’s empty?[/quote]
You got it! Remember, crush til you’re scared!
Awesome, I can do that.
Just fine-tuned the mill frame positioning on the base I made. Waiting on the hopper and then I’ll see what she puts out (hehe)!
One nice thing I discovered about using a credit card: it makes it easier to ensure that the adjustable roller is parallel to the top two rollers. Makes a good baseline to tighten from.
[quote=“ickyfoot”]Awesome, I can do that.
Just fine-tuned the mill frame positioning on the base I made. Waiting on the hopper and then I’ll see what she puts out (hehe)!
One nice thing I discovered about using a credit card: it makes it easier to ensure that the adjustable roller is parallel to the top two rollers. Makes a good baseline to tighten from.[/quote]
I’m not really sure how much that matters. The JSP is purposely built so the rollers aren’t parallel and produces a great crush.
Yeah, the monster mill instructions say it’s not necessary, but that it will wear out the bushings faster if it’s not horizontal. I’m also the kind of guy who lines up the place mat with the edge of the table, so there’s that, too 
.
[quote=“ickyfoot”]I checked 'em all…no one has 'em, except one, but it only goes down to .040". Really lame/annoying. I’ll eventually just buy one online, I guess. If supplies arrive in time for me to brew this weekend, though, I’ll just go with the credit card and see what happens.
DUH! My neighbor is an auto mechanic. I’m sure he’ll have one I can borrow, and I’ll just mark some settings.[/quote]
Try your local small engine repair shop and/or local home improvement store (i.e., not a big-box home improvement store). They usually will have them, too.
[quote=“ickyfoot”]
One nice thing I discovered about using a credit card: it makes it easier to ensure that the adjustable roller is parallel to the top two rollers. Makes a good baseline to tighten from.[/quote]
Out of curiosity, I checked my BarleyCrusher and a credit card just fits between the rollers with a little bit of “grab”. I determined my gap by tightening slightly each batch until I had a slow batch, then backed it off very slightly on the next batch. That’s pretty tight though, if I was using it for the first time I’d consider malt conditioning or having a handful of rice hulls on hand.
I probably (and did) would have used the factory setting for one batch before tightening further.
It won’t be the end of the world if it sticks, though, I’ve always been able to get it flowing again. If you do get a stuck runoff, stir and re-vorlauf, opening the valve slowly and not as wide. That will help keep the grain from getting sucked down into an impermeable mass. Usually, once you get it running, you can open the valve wider if you do it slowly.
I believe that a lot depends on the malt you are crushing. I find that some malt, (possibly very dry malt) tends to have husks that shatter into small pieces, which is when malt conditioning can help. Look for husks that are essentially whole, just split open like the pages of a book.
That’s interesting, I didn’t know that about those mills. That probably helps prevent stuck mashes by leaving some grain husks less shredded. I’ve found that, with troublesome sacks of malt, that I could just condition a couple pounds of malt and that would be sufficient to remove any problems with the flow.
I would’ve done that except the screws that hold the adjustable roller in place loosened in the mail.
Interesting thought regarding the angled roller helping with slow runoffs…
So, when I calculate efficiency after sparge, should I use the total volume I put in, or the total volume in the kettle? If the former, I just got 92%, otherwise I got 77%, which is still 6% better than my previous best. I’m guessing it has to be the latter, but thought I’d check.
Use the collected volume to calculate efficiency. This, along with gravity, tells you how much total sugar was extracted from your grain, and efficiency is comparing this collected sugar to the total sugar in the grain under ideal conditions.
Gotcha. So, to calculate the conversion efficiency you use total volume in before first runnings, for mash efficiency you use total volume into kettle, and for brewhouse you use total volume into fermenter?
If that’s right, conversion is 91% and mash is 77%. Here are the numbers:
Grain:
10 lbs 2 row
1.5 lbs c-60
.5 lb biscuit
6 oz chocolate malt
Pre-sparge vol in: 8.5 gallons
Pre-sparge gravity: 1.082
Volume out: 7 gallons
Kettle gravity: 1.050
Essentially, but you need to account for the volume added by the dissolved sugar in the mash. You can easily determine conversion efficiency by dividing your first-running/pre-sparge gravity by the gravity expected from your mash thickness. [urlhttp://braukaiser.com/wiki/index.php?title=Understanding_Efficiency#Measuring_conversion_efficiency]This table[/url] will give you that expected gravity.
However, your 8.5 gallon pre-sparge volume must be wrong, since that was your mashin + sparge volume. Use you mashin volume to determine your mash thickness, then look at that table to determine your conversion efficiency.
If you mashed to achieve half your runnings from the first-runnings, you would have mashed-in ~5 gallons, which would have given you a mash thickness of 1.62 qt/#. Then, you would expect ~1.077 at 100% conversion. So, perhaps you mashed slightly thicker than that?
Sorry, you’re right. Total volume in, pre-sparge, was 5 gallons. I mashed in with 3.5 gallons and let it rest for maybe 75 minutes. Started at 152, ended around 149, and then I attempted a mash out by adding 1.5 gallons of boiling water. It wasn’t enough to get it up to 168, but I let it sit for another 10 minutes anyway. Then, I drained, took a gravity reading (1.082), sparged with 3.5 gallons, and took another reading (1.050).
If I hand calculate the potential pppg using Palmer’s chart
http://www.howtobrew.com/section2/chapter12-5.html
, I get 449 pppg max potential extraction for the grain bill. 449 / 5 gallons = 89.8. I got 82, which is 91%. And, actually, my new hydrometer measures my tap water low by a couple points, but until I have a chance to test distilled, I’m going with actual readings.
In the event that something about my calculations is wrong, another factor is that I weighed the grains myself. Maybe the scale is off? It’s new and cheap, and I haven’t checked it against anything yet. Either that, or my 1 qt measuring cup is off, but I checked that by weight and it did pretty well.
At any rate, I feel confident that the new grinder has made a difference. The crush really looked great! Couldn’t find any grains that weren’t completely split open across multiple handfuls.
How did you get 5 gallons out with 5 gal in?
Given the potential extract you give there, I’m guessing 12.5 lb of grain, so 1.5 gal absorption, for 3.5 gal first runnings. 82/(449/3.5) = 63.9%.
Distilled vs. tap water won’t affect the hydrometer reading significantly enough to be seen.
I thought for conversion efficiency you use full volume in, pre-sparge, instead of volume out?
My understanding is that you’re trying to figure out if your mash fully converted the grain. Because converted sugar is dissolved in all the water added, not just the wort collected, you have to use the full volume to know how much sugar you extracted. Am I off on this?
If not, I think I’m starting to understand the concept of mash vs. brewhouse efficiency. One is a measure of how much sugar you converted, the other is a measure of how much of that sugar actually makes it into the kettle vs. being left in dead space, water absorbed by the grain, etc.
