[bluesman]

I know you have a JSP Maltmill with a fixed factory setting which should be .039". Have you checked that mill gap setting?

No, EXCELLENT point. My inexperienced eye thought the milling was a little fine. I will measure the gap and also take a picture of some milled grains.

I use an adjustable JSP.  I have the gap closed almost as far as it will go.  From the time I start my mash runoff til the time I finish my sparge runoff takes 15 min. for about 8 gal. of wort.  That includes vorlauf for the mash, adding the sparge water, and vorlauf for the sparge.

Denny...have you measured your mill gap setting on your JSP? I was just thinking that the millgap setting on your JSP might be a good benchmark for homebrewers trying to achieve an optimal crush.

If we assume the typical mill roller runout to be within .001", one should be able to find an effective gap of .002" in areas when fully closed. We know that a fully closed setting is not practical because the grain wouldn't be able to pass through the mill. I see two factors to consider when setting your gap, one is the performance of the crush (passing speed) and the second being mash efficiency. Although I think passing speed takes a back seat to efficiency at least to me anyway. The density of the crush will directly effect the runoff. The finer the crush, the slower the runoff just as the coarser the crush, the faster the runoff. So dialing in the crush can effect several different parameters of the process. Perhaps we should prioritize the parameters and dial in the crush from that point. Personally, I think efficiency should come first.

Has anyone done any experimenation on mill gap setting vs. efficiency?

[denny]

Nope, I've never measured it.  Maybe I'll remember to do that one of these days.  I closed it all the way and then opened it enough so that I saw the rollers just barely move. 

[oscarvan]

I found this Brew Strong show fairly informative. http://s125483039.onlinehome.us/archive/bs_masheff101909.mp3

Listened to it several times- now I feel better about backing off my gap. Especially when I noticed it didn't impact my efficiency at all.

Very cool..... now on my iPhone. Will listen to it on my next trip.

[malzig]

The 96% was my percentage of 75%, IOW how close did I get to the malter's assumed brewhouse efficiency.

I've never heard of anyone doing this calculation before.  What makes you think the maltster expects you to get 75% efficiency?  I think the maltster expects you to get 100% conversion and then whatever lauter efficiency your system happens to have.  I doubt they expect the professional breweries, for whom they produce most of their malt, to be getting only 75% mash efficiency.

As far as luater speed goes, I strongly suggest malt conditioning if you have trouble with slow runnings.  I use a round cooler and a very tight gap, but get runoff as fast as my 1/4" ID valve will allow.  Maybe 5 minute or so.

[oscarvan]

Ok what is malt conditioning?

After listening to the BN episode on mash efficiency I have concluded that my grain may not be crushing properly. All the husks are shredded. So, I am going to try wetting them prior to grinding.

But first I will check the gap. In the middle of 5 days of running around the country. Brewing again wed or thu.

[Hokerer]

As usual, Kai is the man...
http://braukaiser.com/wiki/index.php/Malt_Conditioning

[richardt]

Speaking from experience here:

When "malt conditioning" do not over-wet the grains.  Male Logic ("more is better") does NOT work in this situation.  Read the article and stay at or under the ml H20 per lb grain limit suggested.

If you do not, then you will create a sticky dough that coats your rollers.  If you continue to persist in male stubborness and determination in attempting to crush the grains with corndog rollers it will be very, very difficult (with a hand crank) or you could quite possibly burn out your drill.  I did just that.

You will have to take apart your grain mill and soak the rollers/corn dogs in water to get the concrete-like dough to soften up and come off the rollers.  In my case, I then added the "corn dog" slurry to the mash tun (no loss of efficiency ).

[maxieboy]

Verify the gap. Odds are, it's good. I've got the same mill, never checked the gap(crush always looked great), and checked my efficiency when I first got the mill(approx. 80%, batch sparge). I basically always hit my preboil gravity(if anything a tick high) ever since. I'd say get your process and efficiency calculations down before adding more work and another variable into the mix. Just the way I roll... Good luck!

[oscarvan]

My conversion is fine, efficiency in the low 70's. It's the VERY slow draining of the bed that's the problem. As I said, the husks are all torn up.....

OK, read Kai's writeup. Intuitively that was my plan, but it's nice to have some numbers.

[maxieboy]

How does this look compared to yours?

[euge]

How does this look compared to yours?

That looks about right. I get this without conditioning. I've played with the gap for years and settled on a wider setting.

It may be your crush is too fine Oscar. Most people have at least some problems with their first AG- whether it be with efficiency or run off problems. Try using some gap-feelers to measure the distance between the rollers. A gap of 0.036" is a good place to start.

Before trying another variable like "conditioning" your malt first try adjusting gap settings. I think the "crush until scared" philosophy is a bit overdone from time to time. You should get good extraction and efficiency numbers without resorting to a superfine grind.

[oscarvan]

My gap is not adjustable ...... On the road right now, but will measure first thing Wed morning and take a pic. Looking at the above visuals I think I may be too crunched up.

Does age of the malt matter?

[maxieboy]

A coarser crush. From Howtobrew.com.

[malzig]

Before trying another variable like "conditioning" your malt first try adjusting gap settings. I think the "crush until scared" philosophy is a bit overdone from time to time. You should get good extraction and efficiency numbers without resorting to a superfine grind.

It's not like spraying a little water on some of your malt is a huge chore or much of a variable.  My efficiency was >85% before conditioning and >85% after conditioning.  The one benefit that I did see around the same time as I started conditioning was crystal clear beer.  I can't credit it to malt conditioning, since I was reliably fixing my mash water by then, but malt conditioning has the potential to decrease phenol extraction and therefore beer haze.

It's relatively effortless, takes little time, and won't change much of anything about your brewday.  What it does do is significantly improve your husks and your lauter if you're coming close to a stuck sparge.

[oscarvan]

It's relatively effortless, takes little time, and won't change much of anything about your brewday.  What it does do is significantly improve your husks and your lauter if you're coming close to a stuck sparge.

That's where my thinking is at right now.