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Meat Burner
04-02-2007, 10:08 PM
With help from this fantastic site, I have been trying to fab a firebasket for my bandera. I like this smoker for what I do. A big learning curve!
Here is my concern. I am making a firebasket with all four sides of 1/4" steel, heavy expanded metal bottom, made a fire grate, firebox baffle, and heat baffle (THANKS TO BANDERA 101). My fire box is approximately 13 X 17 and 5 inches high. The 5 inch solid metal between the firebox and smoke box only would leave about and inch and a half opening. Should I cut this end down to 3 inches to allow the designed amount of air flow into the smoke box? It looks like there would not be enough opening into the smoke box. I simply don't know and would really like your thoughts.
Help me....please help me!:grin: :grin: :roll: :icon_smil

The_Kapn
04-02-2007, 10:15 PM
Do not restrict or reduce the opening to the smokebox!!!!!!!!!!
Period!
That side of the basket must be lower than or larger than the opening to the smokebox since you are using solid metal there. If you were using expanded metal, it could go higher and still allow airflow.

In addition, with solid sides, the only real source for airflow is through the bottom of the basket and whatever air comes over and around the top.
You will need to assure the bottom gets cleaned out as the burn progresses.

Airflow is King--reducing it in a controlled manner is the key to long basket burns in a Dera (or anywhere else).

TIM

Meat Burner
04-02-2007, 10:24 PM
Kapn, do you thing the 5" sides are too high. The three will be be at the intake end and both side and the baffles will be 5" as well. My plan was to lower the end going into the smoke box to 3" to not restrict the airflow into the smokebox. Does that sound right?

smokinbadger
04-02-2007, 10:30 PM
I built a charcoal basket for my bandera last year and it has worked very well for me. I used expanded metal on the air inlet and smoke chamber sides as well as the bottom of the basket. The other two sides are solid metal. I included baffles to get the "S" charcoal path to prevent the whole thing from lighting off prematurely. Here's a picture of it after a couple of uses:

http://lh4.google.com/image/smokinbadger/RWkYfmt4ABI/AAAAAAAAACI/qlQPaiPFPGw/s400/charcoal_basket_2.JPG (http://www.bbq-brethren.com/forum/%3Ca%20href=)

The advantage to having expanded metal is that you can have charcoal stacked high but still not completely restrict the airflow into the smoke chamber. The charcoal in the basket provides some porous flow resistance for the air and combustion products, and the geometry of the basket further increases pressure resistance. Therefore, there is no need to further restrict the airflow. In fact, doing so will probably result in rich combustion, leading to nasty tasting partial combustion products which you do not want to eat!

Let me know if you want any more information, such as dimensions, etc. Good luck!

The_Kapn
04-02-2007, 10:34 PM
I am not going to quote deminsions since I sold my Dera and do not have it to measure.

I will guarantee you this--keep that opening from the firebox to the smokebox "OPEN" or you will be wasting fuel and meat. :-D

In the Dera--you need clean airlflow from the intake to the exhaust.
Then, to control heat, you start restricting the INTAKE AIR and not anywhere else in the flow.

I can give you several thousands of dollars worth of examples of what happens when you restrict the airflow DOWNSTREAM from the intake area :redface: :redface: Been there, done that! :mad:

TIM

david
04-02-2007, 11:28 PM
Then, to control heat, you start restricting the INTAKE AIR and not anywhere else in the flow.
:biggrin: LMfarkingAO :biggrin:

the top hatch on my bandera is warped an inch off the box on the front left corner (it might only be 1/2 inch and the fire-box itself is a 1/2 inch down)... theres no restricting airflow in mine anymore. If I can't control the fire, I don't control the heat.

Meat Burner
04-03-2007, 12:29 AM
I have experienced the wonderful result of restricted air flow. If we got ribbons for the worst of the worst, I would rule the world in chit Q.
Trying to learn from the Brothren here as to what big mistake not to make with air flow...the most important skill. My makeshift baskets thus far have produce too quick burn rate. I realize the Bandera requites more attention, just trying to extend the sleep time for overniters.
Would you think the end between the basket and the smoke box should be only expanded metal and not solid metal 3" high at all?

Oldbob
04-03-2007, 07:04 AM
That 'Dera is definately gonna need good airflow My Basket is made solid on the sides and expanded on both ends with 1/2" rebar on the bottom,and dont forget to leave 2-3" between the ash pan and bottom of the basket for airflow...this is critical in my estimation.I lined the firebox with firebrick and stood the brick on their side against the outside walls and I lay the grate of expanded metal on these side wall bricks,the basket sits on the grate and leaves app. 3" of airflow under the basket.I would be glad to post a picture tonight if that would help You.Just My $.02

nmayeux
04-03-2007, 07:17 AM
This is the solution that I used to ensure that my basket did not interfere with the air flow or adding sticks from the door on the side of the firebox. It is pretty simple, but it has proved to be a great basket. You can see that the brass baffle is well above the top of the back wall of the basket.

Pork Chop
04-03-2007, 08:49 AM
Great thread....keep those ideas and pics coming.

Meat Burner
04-03-2007, 08:52 AM
I would appreciate pics...thanks!

Oldbob
04-03-2007, 09:37 AM
I would appreciate pics...thanks!

I will try to post some pics tonight Meat !!

Oldbob
04-03-2007, 06:06 PM
Here ya go Meat !!
Smoke King Deluxe Fire Basket with firebrick lining the firebox

http://i144.photobucket.com/albums/r174/bob_indy/basket7.jpg

Picture of the basket

http://i144.photobucket.com/albums/r174/bob_indy/basket5.jpg

another pic of basket in place

http://i144.photobucket.com/albums/r174/bob_indy/basket2.jpg

Picture of the smoke box with stainless tray in place...I Line the tray with Heavy Duty aluminum foil for ease of cleanup

http://i144.photobucket.com/albums/r174/bob_indy/basket9.jpg

I Hope these help You some,as I said before the Air Flow is Very critical.I have approximately 3" of air space under the fire basket.The firebrick "Splits" work out great for this application...I think I had to trim just one brick on the front next to the smoke chamber to get the proper fit.The pan is removable to empty the ashes.I also have baffles for the FireBasket...but I didn't show them in place....sorry.

Meat Burner
04-03-2007, 09:01 PM
Oldbob, that helps a lot. That looks well built. Without baffles in the firebox "S" pattern, the whole thing was firing up too quickly on me. I am trying to slow down the burn rate to extend the burn time. Do you not have that problem?

Oldbob
04-04-2007, 07:36 AM
Meat...This isn't My Basket in this picture...but I have baffles exactly like these that are adjustable...They work well for me...I run with the Smoke Box Exhaust wide open at all times and make all adjustments on the airflow at the inlet to the firebox.I have never tried the "S" pattern burn...I Might make a set of baffles and try it...I know some Brothers swear by it.

http://i144.photobucket.com/albums/r174/bob_indy/BasketPicture002.jpg

Meat Burner
04-04-2007, 08:05 AM
Oldbob, thanks. This is helpful.

ibcleary
04-05-2007, 01:26 AM
Meat,
Check this out. I'll give you the final result in about a week when I get the new non-galvanised metal welded up and a smoke in. Results on a test run were good, about 3 hours. I might lenghten the baffles a little so there is not as much coal burning when it turns the corner. It holds a 18# bag of coal.

6696