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  • #16
    Well she's up and running. Completed the racks and keepers yesterday. Thoroughly washed every surface and hosed it out. Gave her a solid rub down with oil and ran it up to 350 degrees for 3 hours. Man this thing is way different than my offset.

    It's going to take me a while to figure out how to control this precisely. I have a few questions for anyone that has an insulated smoker.
    1. How easy is it to reduce temps on your smoker? I'm finding with all the insulation and thick steel she holds temps for a long time. I'll have to be careful how quickly I get it up to temperature on initial start up.
    2. I got her going again today in attempts to control per a typical smoke at 225 degrees. She sat dead at 250 degrees with the damper almost fully shut. I checked for seal around the fire box and it's tight. Any suggestions on better control? The fire is definitely burning cleanly but I feel like I shouldn't have to close the damper that far. Although it's very efficient with charcoal/wood at that amount of air flow.
    3. Is everyone using a water pan? I ended up putting a water pan in to bottom and that hepled but I was hoping I didn't have to use one with the thicker baffle plate.






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    • #17
      Man that looks great!

      Here is my primer on insulated cabinets. They hold heat...it is hard to lose heat out of the box once it runs up, so you have to get control of that fire while the temp is on the way up so it doesn't overshoot. If it gets too high, you can't just open the door and let it escape, because when you do it lets oxygen in to stoke the fire...so your only recourse if to close down the dampers and let the heat bleed out...that can be tough to drop the temp and it may take a while. You can easily open a damper and nudge the fire up, but dumping it out once it skyrockets is a tall order.

      If you want to moderate the temp, you may consider a water pan...it will absorb temp from the fire and put off steam at 212° which is close to your desired temps of 225-250. Otherwise you will need to pare back on the heat by building a smaller fire to begin with....if you have a large fire pan and just fill it up and let it rip, you may exceed what you want for smoker temp. I usually fill up the firebox and start a small fire and let it work across on it's own...I don't let it have a lot of fire to start with or else the temps will be high. My insulated cabinet with 2 1" ball valves open will sit at 225-250 all day long. That's not a lot of air. The Iron Maiden will sit at 250° with the slide control just cracked...in fact I don't go through enough splits to keep a strong bed of coals...I occasionally need to add a bit of lump charcoal to keep a bed of coals to ignite the splits.

      I originally built my cabinet to utilize a food service steam table pan that was stainless. It worked really well. Now, having said that, I spent an inordinate amount of time cleaning that thing. So I decided to build a "receiver" baffle plate to accept a disposable aluminum pan...after the smoke, I just threw it away! Now, when building the receiver I originally had about 1/4 inch separation between the bottom of the disposable aluminum pan and the receiver "plate"...all the sudden my smoker worked way differently than it did with the steam table pan. I backed up and cut that 1/4" off so the receiver and foil pan touched. Now it operated as a heat sink to smooth the temp transitions of the smoke chamber, and man does that make the smoker temps stable. It does use a bit more fuel, but now that you know the concept, you can decide how you want to roll with your rig.


      If you need to run with the damper almost closed, that's OK...the fact is that insulated cabinets don't need a lot of fire to maintain a good temp...as long as it's breathing and the smoke is thin and blue, just be proud of the fact that that sucker is so damn efficient!! Trust me, your charcoal bill just went down which leaves more bank to buy meat!

      As you have noticed, the insulation makes one hell of a difference...After a few cooks you will know the idiosyncrasies of your cooker and how to make it sing. Nice job on that build and welcome to the insulated smoker club!
      Last edited by BBQ Engineer; 10-15-2016, 07:38 AM.
      BBQ Eng.

      The "Cow Girls" were adopted from the shelter, and found on petfinder.com.
      Adopt a homeless pet - http://www.petfinder.com
      I built the Iron Maiden - Iron Maiden Smoker Build

      Over 5000 unreadable posts...Photobucket can kiss my ass...they will never get a dime. I will not pay a ransom.

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      • #18
        BBQ Engineer that all makes perfect sense and from my short time using the smoker it explains a lot of the behavior. I did some experimenting yesterday with the water pan. I used an extra broiling pan I had and that seemed to work great at keeping the temps to 235-240 degrees. I already have a lip from the gasket c-channel and I built the first rack up at 5" so I shouldn't have any issues with clearance for a 4" aluminum pan.

        It's funny you mentioned the 1/4" stand offs, I had the same idea last night. I was thinking a short 3/8" stand off and another 1/4" steel plate with "vents" around the side to let the hot air circulate. What characteristics did the stand off change?

        I must admit compared to my old offset this thing is just awesome! Having an air tight seal and insulation helps keep temps so stable. I did find it takes an hour to adjust temps down 15-25 degrees. Recovery after opening the cooker door is so fast once the smoker is up to temp.

        Today will be the true test, I have an 11lbs brisket and two racks of baby back ribs in there right now. Last night I did a quick run with some wings for dinner which worked out great. My ultimate goal is to be able to sleep a few hours through the night so I don't have to wake up at 3.30am to start cooking. Thanks for the warm welcome, hopefully I find time to sand and paint next week!

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        • #19
          Originally posted by fasttruck860 View Post

          It's funny you mentioned the 1/4" stand offs, I had the same idea last night. I was thinking a short 3/8" stand off and another 1/4" steel plate with "vents" around the side to let the hot air circulate. What characteristics did the stand off change?
          Here, let me post a couple photos to describe what I was talking about...

          Originally I had a stainless steel food service pan that blocked about 80% of the heat from the firebox to the smoking chamber. It acted as a heat sink for the heat and turned that into humidity...it absorbed the heat and turned that into moisture. The bottom of the food service pan is in direct contact with the heat from the fire...The food service pan acted as my baffle plate.


          After I got tired of cleaning that thing, I built a receiver to hold an aluminum foil pan. This was the same footprint as the stainless steel food service pan and just dropped into the same hole.


          My first attempt at this, The foil pan was just supported by the rim, and the bottom was easily 1/4 inch above the bottom of my receiver baffle plate. There was no real heat sink action that occurred as the heat just flowed around the foil water pan. The temps were so high and I was scratching my head as to why the difference in operation between the stainless steel food service pan and the disposable foil pan...then it dawned on me. So, I took the receiver insert out, cut it so the foil pan made direct contact with the baffle plate at the bottom of the receiver insert, and Viola! It worked as I had become accustomed to having it work. In this photo you can see it sits directly on the bottom plate so the heat transfer to the liquid in the foil pan is direct.


          Hope that helps and isn't too confusing. It sounds like you're gonna get this thing mastered. I will tell you my smokers don't care if it is -4° with a brisk northerly wind...they act the same as they do when it's 85° and sunny. Consistency is the name of the game and it looks like you have a beauty there. I can't wait to see some of your creations as you get that thing online!
          BBQ Eng.

          The "Cow Girls" were adopted from the shelter, and found on petfinder.com.
          Adopt a homeless pet - http://www.petfinder.com
          I built the Iron Maiden - Iron Maiden Smoker Build

          Over 5000 unreadable posts...Photobucket can kiss my ass...they will never get a dime. I will not pay a ransom.

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          • #20
            Yes..since you are not heating the pan directly over the fire..it needs to be in contact with the baffle plate for be effective. That’s 540 calories of heat eaten up by every gram of water vaporized. As anyone with an uninsulated rig in the rain can tell you.. that’ll drop temps really efficiently
            In God I trust- All others pay cash...
            Check out the Mad Hunky and products at https://madhunkymeats.com or https://www.facebook.com/MadHunkyMeats
            Lang 60D, The Beast, 18 and 22 WSM, Brinkmann Backroads trailer, Weber 22 Kettle, gutted MB burning watts

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            • #21
              Tru-Dat Rich. And if the water pan isn't eating up that heat, the temps can get really high if you don't utilize good fire control. Since I have run my smoker so much, there are times I don't use the water pan...I just exercise better fire control...I have never noticed a difference in the "moistness" of the end product using a water pan or not. The best reason to use it is to assist in smoothing the temps in the smoking chamber.
              BBQ Eng.

              The "Cow Girls" were adopted from the shelter, and found on petfinder.com.
              Adopt a homeless pet - http://www.petfinder.com
              I built the Iron Maiden - Iron Maiden Smoker Build

              Over 5000 unreadable posts...Photobucket can kiss my ass...they will never get a dime. I will not pay a ransom.

              Comment


              • #22
                Yaknow...maybe a cup of water tossed in below/beside the firepan in those “Damn got it too hot” situations? I guess I don’t know enough about the construction here, but if that is feasable, it would help I’d think.
                In God I trust- All others pay cash...
                Check out the Mad Hunky and products at https://madhunkymeats.com or https://www.facebook.com/MadHunkyMeats
                Lang 60D, The Beast, 18 and 22 WSM, Brinkmann Backroads trailer, Weber 22 Kettle, gutted MB burning watts

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                • #23
                  He's final interior arrangement with the 4" roaster pan. This held a perfect 225 so that's what I'll use from now on.

                  Ribs are off the pit and gone! I had to separate the point (was really thick) and the flat, although I probably could have fit it in one shot. The brisket is still on the pit so no money shots until later.







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