Grain Mill type and efficiency

I'd assume this has more to do with temperature variations in your measurement...than milling.

 

Measuring equipment is temp sensitive...not sure how else to phrase it.

 

http://www.howtobrew.com/appendices/appendixA.html

He's saying that your difference in OG is due to errors in temperature measurement when comparing the wort OG from the boil/mash to the cooled post boil wort.

 

Hydrometers are calibrated to a certain temperature (usually 60F) so the temperature of the wort you measure will affect the measurement. You need to adjust your hydrometer measurement for the temperature of the wort.

As barfdiggs linked...
http://www.howtobrew.com/appendices/appendixA.html

 

Can you take a pic of your crush and post it?

 

Are you saying that a recipe tells you to expect at 75% efficiency to get an OG of 1.060, but you only get 1.054? That could be a crush, water or lautering problem.

I suggest trying pre-crushed grain and testing. I have had months old crushed grain in a recipe and never noticed a difference.

 

No, he is saying that his gravity reading at flameout is 6-8 points higher than his gravity reading taken after cooling the wort down to pitching temperatures. The comments above have addressed that concern. It's been explained to him that hydrometers are calibrated to a certain temperature and that he needs to adjust his hydrometer reading based on the temperature of the wort used.

As a side bar, he also asked about how to adjust a corona mills gap space. I've never used one and have no idea.

He is also asking whether buying precrushed grain from an online homebrew supply that will take 7 days to ship to him is a problem. It should not be a problem, but if he lives in New York like his profile says then I have no idea why he would be ordering grain from a place that would have it in transit for 7 days. Morebeer's new PA location should be able to get it to him in 2 days. Grape and Grainery out of Ohio would probably take the same.

 

I never used one of these mills, but it sounds like you are not getting as good a crush as you like. There is no problem having grains crushed 7 days in advance by a home brew shop. I would not hesitate to use pre-crushed grains over the course of several months.

 

I think JohnSnow may have misread your initial post and assumed that you were reporting gravity readings made at two different temperatures, and then several others followed his lead. But what you are really asking about, if I am not mistaken, is the quality of the crush from a Corona mill vs. what you get at a homebrew shop.

I get my grains crushed at the homebrew shop. The consistency of the crush varies from shop to shop and even from time to time within the same shop. In the last 3 or 4 years, I have had mash efficiencies that range from 60% to 90% and I believe the crush is responsible for part of the inconsistency.

One advantage of crushing them yourself is that the quality of the crush is under your control. Even if you are not getting a great crush, having a consistent crush may be more important to you. I have inferred from those that post in this forum that many homebrew mills will give you high consistency and high quality. However, the Corona mill reportedly shreds or shears grain as opposed to crushing between roller mills. This may not be the best for getting high efficiency mashes. Others with more experience crushing their own grains may want to comment.

 

Yep. I haven't used a corona mill, but I did once look closely at the design, and it seemed to me that it was really designed for grinding rather than crushing. So, efficiencies aside, I couldn't recommend it.

I suspect there will be some replies now along the lines of "I use a corona mill and I make great beer." Fair enough.

 

LMAO. Hang in there Ilanko!

 

Ilanko: what inchrisin meant was...
Can you take a picture of your crushed Grains?

 

Maybe he wanted him to take a picture of the person he has a crush on.

 

@Ilanko you need a close up pic of your crushed grain

"I have a Corona mill and make great beer @VikeMan !" To adjust the gap on your corona mill you must turn the center bolt on the outside of the plates. However, looking at your pics it looks like that is just cotter pinned in? That could be the problem.

Need a better pic of the outside plate bolt as well.

Worst case you adjust your grain bills for the lower efficiency.

 

This sounds like a good solution. Being off by 6-8 gravity points is not that bad. Add an extra pound of base malt for $1-2 and the problem is solved.

Followup thought: My arms get tired just thinking about crushing 10 lbs of grain with a Corona mill.

 

That was not apparent from your first post, thank you for clarifying.

Please send a picture of your crushed grain to help us see if might be under crushing. As others have said you can crush twice, adjust the mill to make your crush finer or just increase the amount of grain in your recipe to account for lower efficiency.