First cook on my Cookschack will be an overnight Brisket tonight

WyoJim,
Sounds like your are trying to make it more complicated than it needs to be

I usually season the brisket overnight, put it in the cookshack using 2-4 oz of wood, set the temp 225 degrees. Set it and forget. (If overnight I might set it at 200 and bump up the temp in the morning)

I take it out when the brisket reaches 195 degrees, foil it for 30 - 60 minutes, slice and serve. Haven't had a bad one yet.

Generally the meat temperature is going to be a bit lower than the average oven air temperature, at least until it's pretty well dried out. I'd go with Greyn's advice above. Or see the Brisket 101 in the Smokin' Okie Barbecue Guide.

Wyo.

I don't think it's a good idea to try to "second guess" the cycles of the smoker. Set it on a temp that you want, say 225, and the "average" will be that temp. There will be highs and lows, but you want an average.

If you try to outthink this think, you're making it too hard. Have fun with it and as some of the forum members say, it's not rocket science..it's art.

Welcome to the group.

Smokin'

Well we got a weather front last night and I chickened out on leaving my brand new smoker out working in the rain.
Put the separated brisket on this morning with the smoker set at 225 degrees. 4 hours later the flat was at 167 degrees and I foiled it and the point both. At 6 hours the flat was at 196 degrees. I turned the smoker sown to 185 degrees. My Polder said the smoker came up to 199 degrees. I left it there 3 more hours. Took it off and the meat was at 200 degrees. Left it sit 1 hour, then sliced it. The flat sliced but the point was pulled beef. DELICIOUS and TENDER and MOIST.

I might add that this Brisket was an ungraded Walmart piece of meat, 10.5 pounds. I believe that would mean commercial or worse. But it is truly a success. Thanks to my friend that manages a Franchise BBQ Restaurant. He told me how to do them. I have been doing them this way on my WSM for quite a while and they have all been good. This was the easiest one yet, not much fire tending.

The temperament of my smoker changed considerable with a load of meat in it and changed again with the meat foiled. I know you don't want to hear the numbers so I won't post them. I know I am supposed to set it and forget it, and I will after I am familiar with what it is going to do.

Tomorrow....Spare Ribs!!!...and I won't upset anyone by disclosing my plan before hand.

But you've already revealed too much of the plan and thus made advice irresistible. Try the Ribs 101