1. Some of the links on this forum allow SMF, at no cost to you, to earn a small commission when you click through and make a purchase. Let me know if you have any questions about this.

Steel thickness on Firebox

Discussion in 'Reverse Flow' started by kenny8906, Oct 11, 2010.

  1. kenny8906

    kenny8906 Newbie

    Guys,  I'm in the process of building a reverse flow w/ a square firebox.  Will 3/16" plate still work for the firebox or should I go with 1/4"?  Also what about the thermal plate, what is the sugguested steel thickness for it?


  2. eman

    eman Smoking Guru Staff Member Moderator OTBS Member

    IMHO , You need the thickest steel you can use on the fire box as this is going to get hotter than any other part of your smoker. thermal plate i'm not sure but i'm sure that someone who has done a build will chime in and let you know.
  3. dick foster

    dick foster Smoking Fanatic

    If you can I'd say line, laminate or even insulate the firebox if at all possible, especially the top. Say line it with a piece of  aluminum sheet covered by a yet another sheet of steel. Even the thin stuff in mine is holding the paint.   

    For the thermal plate I assume you're talking about the bottom of the cook chamber or the RF plate in which case the thicker the better as it's thermal mass. That will help even out the heat and eliminate hot spots. Since is mostly a flat piece anyway, try for 1/4" or better. You can always weld pieces to fab any small details or angled parts.  
  4. pineywoods

    pineywoods SMF Hall of Fame Pitmaster Staff Member Administrator Group Lead OTBS Member OTBS Admin SMF Premier Member

    If you can I would go with 1/4" for both the firebox and the reverse flow plate but 3/16" would work if you already had some on hand
  5. raptor700

    raptor700 Master of the Pit OTBS Member

    Wecome to SMF Kenny, I used 1/4 all the way on my build and it works great! I have learned over the years it's best to build things the best way you can! If you don't have 1/4 in. buy some a little at a time until you have enough to do your build. You will be very pleased with the end result if you take your time and do it right!
  6. diesel

    diesel Smoking Fanatic

    I used 1/4 in.  I also made it double walled.  I placed 1 in square tube in the middle for both support and even spacing.  It does get very hot and like others have said. You won't regret it.  Example is my firebox door.  It is single 1/4 piece and I didn't weld a support across it.  It has warped some and will have to go back and add the support bar.
  7. alfa01

    alfa01 Fire Starter

    I see this is an old thread, but I have a relative question to some of the replies posted here.  

    For the guys using thicker steel, or even double-wall fireboxes, where are you burning exactly?  I mean, are you guys using an expanded metal tray, grate or something like that?  

    In my current design, I'm not using a firebox.  I have a horizontal water tank that I place coals similar as one would with a Weber, so I guess it would be an Indirect Smoker.  It works great, cooks well and holds heat.  I would like to gain full use of my racks to be able to put a small hog in there, however.  I think the firebox addition would be a great rout for me.  


  8. joe black

    joe black Master of the Pit OTBS Member

    To be really sure of your question, it would be nice to see a pic of your cooker. My initial perception is that your fire is gong into the bottom of the cooing area. If that's correct, your cooking method is direct. Meaning that the heat is directly beneath the meat. Cookers were built this way for many years. The off-set method or side fire box method, moves the fire box out to the side where only the heat and smoke circulate from there, around the meat and out the smoke stack. This is the indirect method.

    If you will click on my avatar and blow it up, you can see exactly what I mean. All of my smoker is 1/4", except the fire box, which is 5/16".

    Please try to post a pic. Good luck and happy smpkin', Joe. :grilling_smilie:
  9. alfa01

    alfa01 Fire Starter

    Yes.  It is a direct cooker, but I set it up for indirect (meaning the fire and the meat aren't in the same vicinity) when I'm smoking versus grilling.  It's about 40" long so when I setup the coals/wood on the left, the chimney and meat are positioned to the far left to draw the heat and smoke across the meat.  Like I said, it cooks really well, but I'd like to be able to smoke some larger portions without fear of burning or drying out the meat because it's too close to the heat.  

    Really thick material.  I'm living abroad so I have to see what is available in metric sizes.  

    Thanks for the reply.  


  10. alfa01

    alfa01 Fire Starter

    Decided to go another route....Build Thread HERE!