MLT temp loss and adding water

In my first AG I noticed a 10 degree loss over an hour. I did not mix the grains at all during the 60 min rest, and my thermometer was resting by the side, and yes, I was outdoors. But, in the event that this is going to be a standard occurence, can I raise the temp half-way through with more mash water? Should I put less in at first knowing I will be adding more later, or just lessen the sparge amount?
Thanks!

What are you mashing in? Kettle or cooler? We typically have to hit our turkey fryer mash tun with some heat during a long rest. One thing that we noticed during heating or even just letting it sit, you need to stir. Transfer the heat all around and mix it up. Also put the thermometer into different parts of the mash. We try to stir every 5 minutes, and we're thinking about ways to turn something like an ice cream maker motor into a stirring motor. As for the water issue, what qt/lb ratio did you dough in at? If you start at about 1qt/lb, adding a little near boiling water won't be too big of an issue, you'll still have a decent mash thickness. These are my thoughts based on a little experience mashing in an aluminum pot.

1.25 qt/lb, and I mash in a 48 qt cooler.

If you're mashing in a cooler, even if it is outside, you probably didn't lose 10 degrees from the whole mash. We don't normally lose that much in our pot. Try the same thing next time and stir it up once in a while, moving the grain all around the cooler. The heat will even out and you'll probably notice that you didn't lose as much as you thought. My first mash in a cooler will be this summer, I'm still putting it together...but I've heard that guys only lose a few degrees and that's not enough to worry about.

What temp were you mashing at?

154 deg.
Here's a followup Q for whomever... I've seen some recipes that indicate sparge time (ie 170F @ 40 min). Is that how long you should let it sit before draining, or how long you should let it drain?

I deal with temp loss by eliminating headspace in this manner. It' just a peice of 2" foam insulation cut to fit inside the cooler with a plastic wire-tie as a handle. I get almost zero temp loss after an hour. I see no reason why this shouldn't work in a rectangular cooler as well.

That insulation piece looks like a good idea, I may try that when I get mine going. As for the sparging, are you batch or fly sparging? There is no time limit on the sparge, but the goal is to rinse as much sugar from the grain as possible, so it should go slow. Do you add boiling water to the mash to increase the temp to 170 degrees before you sparge? We get the temp to 170 and let it sit for 5 minutes or so, then we start sparging. We then use 180 degree water to fly sparge and let a constant slow flow come out of the spigot, vorlauf, and the sparge from then on should take around 45 minutes.

You definitely need to stir your mash when you add the water to distribute heat but also to get the water to all the grains. Otherwise you end up with "doughballs," which are clumps of dry grain in your mashtun. It usually takes a good few minutes of stirring. Do not be gentle.

Ten degrees is a huge loss over an hour, but it may have more to do with your lack of stirring than anything else.


TL

The big question is, did your strike water temp take into consideration the heat that the cooler will absorb? In other words, did you preheat it? If not, that's where the heat went.

I did preheat the cooler, and I did mix the water and grain upon initial mash in. I just didn't stir thereafter.
To answer Knoltonm's questions: I batch sparge, with no mash out. I'm afraid of over watering and being left with an amount of wort too large for me to boil down (I have a 30 qt and a 14 qt pot, but I obviously want to leave some room in both).
I dig Evet's idea of the foam, and might go with that. I'm also going to be more vigilant about stirring during the mash, and slowing down the sparge.