Help with Numbers - First All-grain Batch

Hello,

So, I cooked up a batch of basic dry stout yesterday... and I have a bunch of numbers but I don't have a firm grip on what they are telling me or what adjustments I should be making...

My grain build was...
6 lbs 2-row
2 lbs flaked barley
1 lb roasted barley.

(Our thinking was for a first batch this was about as easy as it gets and we know exactly what this should taste like...so....)

My strike water was 2.8 gallons. After adding my grains the temp was a little high at 153.6, but since I was more concerned with getting information, I left it there...

The cooler held the temp, which was cool.

I mashed out with another 2 gals at about 200 degrees. First runnings measured about a cup under 3 gallons.

I then added 3 more gallons at 185, gave the grains a few stirs and let that sit for about 15 minutes. Drained that out and ended up with about 5.5 gallons. (Half a gallon less than I planned)

My gravity was at 1.042 which was slightly higher than what I was shooting for, but close enough that I figured I was good.

After the boil, I was at 4.5 gallons (A gallon in boil off seems about where we usually are) and my gravity was reading 1.052 (This puzzles me.. I don't understand why it dropped. We added a half a gallon of water and sealed her up.

So, if anyone has anything to teach me here... I would be very happy to learn.

Thanks.

Post-boil your gravity went up 10 points. That sounds right, since you have the same amount of fermentables dissolved in a gallon less water. Higher density = higher gravity reading.

Something seems a bit odd to me. I would have expected 9 lbs of grain to retain about 0.9 gallons (typical retention is about 0.1 lbs per gallon). You had a retention of 1.8 gallons, which is pretty high, about 0.2 gallons per pound of grain, twice what is considered normal. This could be due to your mash tun design, if it doesn't drain completely.

But it gets a bit odder still, because you batch sparged with 3 gallons but got 2.5 out, so your mash tun ate another half gallon. You should have got back the 3 gallons you put in since the mash tun and the mash were already "saturated" with retained water.

What kind of mash tun are you using? Does it have dead space you can't drain? Test it with water and no grain to see what the MT itself retains.

Your pre-boil gravity and post-boil gravity make sense: 5.5/4.5 X 42 = 51 so 1.052 measured is good.

One thing I have noticed when I batch sparge, is if I slow the drain rate down near the end, I get more wort out. I know everyone says drain as fast as you can, but I think what happens in my case is the wort can't drain out of the mass of grain as fast as the liquid level drops, so the syphon breaks before all the wort has drained from the grain.

In my cooler mash tun, the manifold is lower than the drain hole in the side of the cooler so that to drain completely, the last wort syphons out when the liquid level drops below the drain hole level.

If I close the mash tun valve down some, then the last amount of wort trickles out of the grain bed before the liquid level drops so far that the syphon breaks.

Just some things to ponder while you figure out what's going on.

Like you, I am also surprised that your 1st runnings were near 3 gallons, and you sparged w/ 3 gallons and collected only 5.5 gallons. This is an anomoly that will likely go unexplained as it defies the basic principles unless you errantly left wort in the MT? Other than that you did wonderful!

Hmmm, to be honest, I thought it was odd also that I didn't get the full amount of the sparge out... but being the first time, I just made a note of it and moved on.

So, we have an old 10 gallon round cooler. It does has some significant dead space at the bottom of it that won't drain. My understanding was that each set of equipment is different and I will just need to adjust my mashing to fit the equipment. I will try and measure with water and see what comes up.

I will most certainly work on the draining time... this hobby has taught me patience I never knew I had... I can slow down the drain...

Thanks...