[ericm]

Originally Posted by sparkyaber

one other question, is everyone taking the gravity reading warm/hot and using a formula to adjust to 60? or is everyone cooling the sample in the freezer and checking it then? or are the readings everyone gives at the higher temps?

I ice-bath my samples down to as close to 60 as I have patience for (generally somewhere around 80, heh) and correcting for the temp with the info that came with my hydrometer

[ajf]

For the mash out, I use approximately 1g of very nearly boiling water for most brews, however, I use a thick mash of 1 qt per lb. The best way to calculate the volume and temperature is to use brewing software like Beersmith or Promash, or an on line calculator See Infusion calculator for one example. It seems to match Promash pretty accurately.
To see what sort of gravity you should be getting at the start of the sparge see http://www.homebrewtalk.com/f36/first-wort-gravity-mash-efficiency-68555/
I have measured mine just for fun, but I never recorded it.
I use a refractometer to calculate the wort gravity while it is hot. If you use an hydrometer, you should cool it first. Temperature corrections are very unreliable at temps over 100F.

-a.

[sparkyaber]

Thanks again for doing all of the leg work for me ajf.

[sparkyaber]

Well, two more batches under my belt, got 70% on Sunday, but still had a bunch of sugar left in the wort, (getting 1.020 at the very end of the run off.) I tried to do a mash out to 168 degrees, but did not use hot enough water. Sparge was still about 1.5 hours.

On Wednesday I tried again, but this time I ran the grains through the crusher twice, and used boiling water to mash out (got it to 164 degrees) and also to sparge (still only was at 150 degrees after the long slow fall from the hlt to the sparge arm).
I hit 80 percent. Good enough for me, now I just need it consistently, and I will be elated.
Sooooo, the big question is: was it the double crush, or the mash out that did the trick?

[devils4ever]

I rarely get above 65% and I've done about a dozen AG batches. I've tried tightening the gap, but it didn't help. I'm not sure what the issue is with me, but the "gap" wasn't it.

[ajf]

If you got 70% efficiency with a single crush and your final runnings were still 1.020, then it would indicate that your mash was pretty good, but the sparge could have been better. A finer crush would help improve your mash efficiency (if it was low), but shouldn't have much effect on the sparge other than slowing it down (and possibly stopping it completely if it's overdone).
My guess is that the mash out accounted for most of the efficiency difference, although the double crush would have made a small difference.
If your Sunday brew sparge had ended at 1.010, it would indicate that your sparge was efficient but the mash was not. If that were the case, I think the finer crush would have made more difference.

-a.

[sparkyaber]

That makes sense ajf, I never really thought it through. I still have a ton to learn. Thanks again for all your help.