Well, at this point, I am just trying to determine if there is something in my process that I am doing wrong or can change to better hold temperatures. My basic process has been to heat my mash water 20 degrees over my target strike-in temperature, transfer it over to the room temperature mash tun (60 degrees) let it fall naturally to strike temp (thus preheating the tun) and then dough-in (60 degree grain). I brew in my basement and the temperature in the room (this time of year) is usually right around 60 degrees. I emailed SS Brew Tech support again to see if they have any other advice. They suggested the following:
A few additional tips that might help you reduce heat loss over 60 minutes.
1. If you are not using the upper recirculation port, that is a point where heat escapes, swap it out for the silicone boot or plug the whole with aluminum foil until you ultimately decide to use it for recirculating your mash.
2. Thoroughly inspect your lid seal to make sure that no heat is escaping there. The silicone gasket should be completely resting on the rim of the mash tun creating an air-tight seal. We see this with users all the time, typically there is a sweet spot for mating the lid to the tun, run your hand along the upper rim to insure that you don't feel heat escaping. If you do, rotate the lid 45 degrees and recheck it.
3. Remove the lid as little as possible. Removing it allows all the residual heat from the grist to escape, then even more heat is pulled away from the grain bed to re-stabilize the temp inside the tun. When we run our tests, we never remove the lid, that is how we are able to achieve heat loss statistics of around 1 degree per hour. It may sound trivial, but this is one of the biggest reasons users don't hit their numbers; they are always unnecessarily stirring and checking their mash temp. That is precisely why we put an LCD temp gauge and thermowell on the outside, so you don't need to remove the lid.
4. Thin out your mash, if you are mashing thick at 1.2 qts/lb, thin it out to 1.5 qts a lb. The specific heat of water is very high, and a larger water volume helps to stabilize temps.
Believe it or not, just these four factors should be good for another 1-2 degrees over 60 mins. Give them a try!