Effect of Tuning Plates

Discussion in 'Wood Smokers' started by barnold, Jun 25, 2014.

  1. barnold

    barnold Smoke Blower

    As a newbie on the forum, I posted a thread a couple of weeks ago in which I asked questions about the effect of tuning plates.  I didn't get any response, but now I seem to have some answers myself.

    I modified my OK Joe Longhorn to add a deflector and tuning plates.  All are made from 1/4" steel.  I had hte welding shop make enough tuning plates to cover the bottom with about an inch between them.  After my first cook with them, in which is seemed everything cooked quicker than it should, I removed one to have more space between them.  I cooked a beef brisket and some pork spare ribs last weekend, holding the grate level temperature around 200°F rather than 225°F.  I watched the ribs closely as the cook went along to make sure of the pace. 

    It appears my guess was right: Keeping the grate level temperature lower compensates for the radiant heat given off by the tuning plates.  In other words, without tuning plates the temperature in the lower parts of the cooking chamber is cooler with very little heat given off by the shell of the smoker. 

    Does all this sound reasonable to you folks?
  2. hillingdoner

    hillingdoner Newbie

    Hmmm.  I would think temperature is temperature.  The plates should only act as a tool to even out your temps across the smoker so that you don't have such a high variance between the firebox side and the exhaust side.  If you were accurately measuring the temp at the grate the first time through at 225 where the food was cooking then you should have had no problems.  I say accurately as unsure how you placed your probe and also if you checked it for accuracy before cooking.

    Did you have a meat thermometer running as well?  Times will vary on cook with variance in size of the meat.  A 20 pound cut of meat is going to take longer to cook than an 8 pound one etc.

    You will get radiant heat from the plates, but that should help you with a more steady and even ability to keep the desired temp in the smoker.  What you might (don't know if this is so or not just a guess) be experiencing is the items are also cooking more as they should compared to perhaps how you are used to cooking without the plates.  You may have had larger temperature swings or a problem holding heat in the smoker so that would cause potentially longer cook times.  Now you have the plates they have evened things out and things are cooking at a more steady temp.  Just a theory here.

    Please also accept my post as it was intended which was not a knock on you or your post in the least and certainly not meant if it comes off that way.   Just free thinking.
    Last edited: Jun 27, 2014
  3. pineywoods

    pineywoods Smoking Guru Staff Member Administrator Group Lead SMF Premier Member

    I think the main idea behind tuning plates is you can move them around adjusting until you get rid of hot spots and even temps from end to end
  4. barnold

    barnold Smoke Blower

    I like free thinking and didn't read anything bad in your post.  The free exchange of ideas is what I look for in any conversation.

    Sometimes, I have a tendency to over-think something.  In the case of the difference in cook effect in my smoker now, it will be easy enough to adjust the grate level temperature to get the result I want.  As I thought through the temperature effect a bit more, I guess I can relate it to a regular oven (electric) with heating elements on both the bottom and top.  The bottom element is for baking, etc.  The top element is used for broiling, heating only the top side of the dish.  Before my OKJLh was modified, it was more more like a broiler than a complete oven.  Now, with it acting more like a complete oven, the meat is being heated from below as well as from above, providing more even heat, but also moving the process along a bit faster.  When speed is not what we need, i.e., long, slow cooking of ribs, etc., then the answer must be to drop the cooking temperature with mods like I have now.

    OK - cerebral moment over - back to reality! [​IMG]  
    Last edited: Jun 26, 2014
  5. barnold

    barnold Smoke Blower

    Yep, and on my second cook using the tuning plates, I removed one and changed spacing.  Temps were pretty even from end to end but there's still the "oven" effect I wasn't expecting.  But, that's why we experiment and test. [​IMG]
  6. chef jimmyj

    chef jimmyj Smoking Guru Staff Member Moderator Group Lead OTBS Member

    I just wish to add a Caution that at temps below 225°F any compromised meat, de-boned, injected, or having the surface broken in any way can cause large pieces of meat to take longer than 4 hours to reach a safe internal temp of 140°F or higher. There is no change in the quality or juicyness of beef or pork at a temp of 225° verses 200°F. If you wish to use the lower temp, leave the meat surface intact and either sear the Temp Probe entry point with a torch or other hot piece of metal or wait a minimum of 1 hour before inserting the probe. 99 times out of a hundred, none of this makes a difference but there is always some risk of pushing bacteria into the meat when the surface is broken...JJ
  7. daveomak

    daveomak Smoking Guru OTBS Member SMF Premier Member

    Sounds very reasonable... Alton Brown dedicated an episode to cooking prime rib in the oven.... First part was about how infra red radiation, inside the oven, was how the meat browned.... So, he said, keep your oven clean.... that same IR can come from the tuning plates...
    That being said, if it was true, as dirty as my smoker is, because I don't clean the walls..... The meat would never brown... I'm leaving that alone...
    I don't clean the smoker because down south, they say you can tell from the taste of the meat, how new a smoker is.... so, there is my reason for not cleaning my smoker......
  8. barnold

    barnold Smoke Blower

    I really enjoy most of what Alton Brown does on his different programs - very knowledgeable fellow.

    As to IR inside a kitchen oven, that's what I was relating to with the effect of the tuning plates.  It's good to hear you agree about the IR effect.

    As to the cleanliness of my smoker, I'm with you.  The most I do is use a grill brush on the grates, then scrape the excess yuck from the plates and bottom using a medium putty knife.  I have never washed it down.

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