Partial Mash (attempt) Review

So I made a lauter tun using the standard picnic cooler conversion method, and figured I'd do a partial before I jumped right in and bought the bigger pot and all that stuff.

Anyway, my efficiency was terrible which did not surprise me. I had extra DME lying around that I used to make up for the lack of success in the mash.

So I have a few things to throw out there and see if you guys can help me out...

1) I got a 10 gallon cooler because I intend to do a lot with it. I used ProMash to figure out my strike temp, and according to my crappy thermometer my mash temp was significantly lower than I wanted it to be. Could the huge size of the cooler vs. the 2 or 3 gallons of strike water throw off my expectations and cool down the water more than expected? Is there any good way to compensate for this?

2) When I realized that my mash was in the 140's, I drained a quart of mash water at a time, heated it to nearly boiling, and returned it to the mash (and stirred a lot) so I would not alter the amount of water in my mash. Is this the best technique for such a situation?

3) What kind of thermometer would you recommend for the picnic cooler setup? I used a crappy $5 meat thermometer. I didn't expected this to be adequate in the long term, and got about the accuracy I was expecting. It definitely did not get me a consistent reading... what sort of thermometer would you guys recommend for using with my mash?

I tasted the wort that got out of it and it was sweet, so I think I had limited success with the mash. I'm not demoralized and am trying to figure out what supplies I'm going to get for the all-grain step. I just want to make sure I'm prepared when I get there!

Thanks in advance!

I did a PM on my last batch, but rather than doing what you did, I used my 5 gal cooler to hold 170 deg water that I heated in 2.5 gal batches on the stove.
I then added my grains at 110 in the last 2.5 gal heating, stirring up to 155 then tried to keep at temp on the stove.. not easy. Then I removed the grain bag and put the wort in the boil kettle and used the Cooler water to again flush the grains and keep at temp another 20 min.
Finally the last 2 gal, I used to add in my LME and DME so that I could get them into solution without scorching in the boil kettle on the Turkey fryer.

Like you my efficiency was crap... so I added more DME along with my flame out hops (boiled/chilled) then added Primary as I forgot when the kettle was still on the flame.

Learning all the time and I think that these try's at PM or AG help us figure out what process works best for the individual brewer and the equipment on hand and what we really need.

Thanks for posting, as I'm taking baby steps in the AG direction and reading and learning from your experience is very good.

Cheers and may your beer turn out good.

Did you preheat the cooler with hot water?? I've just started PM's on the stove but remember hearing that heating up the cooler is important. Of course either way (preheat or not) you need to know your average temp drop when the grain goes in.