Firebox Wood Management Experiment Today

[pianov]

I am conducting an experiment today trying to maintain a small hot fire rather than the very large cooler (I suppose) fires that I've used for the past 25 years or so. I wrote a post a few weeks ago when first thinking of doing this. Link is below:

Optimal Fire Management Approach for Stick Burner

I am contemplating a radial new approach (for me) to firebox fire management on my smoker. I have a medium sized masonry smoker that I've used for the past 25 years or so. It is an offset design (fire box to the side of cook chamber). My method of building my fire has been to fill the fire box...

www.smokingmeatforums.com

I have always completely filled my 24" (deep) x 12" (wide) x 20" (tall) firebox (FB) with oak and then lit it. A full load like that would burn for a good 8 hours without adding any wood. It would start out billowing dense white smoke and then as the fire matured, after about two hours, the smoke was thin enough to put meat in the cooking chamber (CC).

I loaded my firebox this morning with about a 1/4-load - I cut all wood down to only 10 inches long so that I could shove all of it to the back half of the FB. And then I only piled it about half-height of the FB. I lit it at 4:45 AM. Even right at the start of lighting the fire it made smoke, but probably 10% of what it used to. And now after 45 minutes of burning, the CC is way up to temp and I have it hovering at 280 F. I like to let things warm up at about 300 F - no higher as much of the CC is made of wood. I have a couple pieces of wood warming in the front half of the FB for when I need them. I'm going to try to keep at most a 1/4-load.

I'm very curious how much smoke will be made when I put a new log on. I had always thought putting a new log (unburnt) on was to be avoided because it would create too much smoke. From my observations so far, I'm thinking that perhaps it won't create too much smoke. We'll see - I'll report back as the burn goes.

I'm going to throw a 14-lb. pork butt and two chickens in the CC soon.

Here is a picture of my smoker. It is a masonry offset type.


Here is photo of firebox door:


Picture of fire about ten minutes after lighting:

 

[sawhorseray]

If you leave your firebox door open when you add a split until it catches flame the white smoke will be minimal and most of the smoke will exit the thru the firebox and never make it to the CC, that's what works for me on my SQ36 offset. Your smoker is a work of art, gorgeous! RAY

 

[Chasdev]

The key is to maintain a proper coal base, not too large or the cook chamber temp will spike and not too small or the smoke from the next split won't get "cleaned" by the heat from the coal base and even though blue, won't be the clear blue smoke we are all searching for and will contain some of the smoke's volitale components that are sour tasting.
Once you get that thing up to temp you can run with the firebox door open or nearly so and manage temps by how much fuel you introduce and when you introduce it.
Here I go beating the dead horse again but sourcing wood that has an internal moisture percentage of 14 to 20 will make your pale blue smoke chase much easier.
Wetter wood burns more slowly but makes a larger coal base which means that once you are at the cook temp you want, you can't add more wood to impart more smoke flavor until the coals die back.
14% moisture content wood burns faster and hotter which self scrubs the smoke and produces a less dense coal base which will degrade at a predictable rate which means you can time the next stick better.
Adding wood to a dying coal base is tricky because you have to time it just right or you loose the heat from the coals needed to scrub the dirty smoke from the new fuel.
Managing the coal base is really the name of the game IMHO.

 

[pianov]

Chasdev wrote: "
"Once you get that thing up to temp you can run with the firebox door open or nearly so and manage temps by how much fuel you introduce and when you introduce it."

Way to hot if fire door left open. I need to close the vent down quite a bit to regulate temperature to my smoking temp. But that's no problem.

"Here I go beating the dead horse again but sourcing wood that has an internal moisture percentage of 14 to 20 will make your pale blue smoke chase much easier.
Wetter wood burns more slowly but makes a larger coal base which means that once you are at the cook temp you want, you can't add more wood to impart more smoke flavor until the coals die back."

Your point is valid and quite important. However, in my case, my oak firewood is right down in the 15% - 16% MC range. It has air dried for several years and kept dry. It is QUITE dry!

"Adding wood to a dying coal base is tricky because you have to time it just right or you loose the heat from the coals needed to scrub the dirty smoke from the new fuel.
Managing the coal base is really the name of the game IMHO."

Yeah. That's largely where my experimenting will be today. When and how much wood to add. It'll be interesting and fun! I've just never had to do this when I would fully load the firebox and just let it burn slowly. I may go back to the old way, but this will be very interesting and informative to observe how this small and hot fire method works.

 

[Chasdev]

I assure you that running with the firebox door wide open will not raise the temp UNLESS there is fuel inside the chamber to interact with with O2 coming in the opening.
What will happen with an open door is complete combustion of small amount of wood which will cause clear blue smoke.
Check out Franklin's rigs while he cooks, once up to temp the doors are open and often a single stick is standing on end and gently burning away.
As an interesting side note, he does not run any type of grate in the firebox, rather he manipulates the coals pile, moving them around, either away from or towards the cook chamber opening as needed to regulate heat.
Other than to get a cold cooker up to baseline temp quickly, there's no reason to stuff a bunch of wood in there, but having done that, you have to wait until the coals burn down to a minimum before adding fuel or you will indeed cause it to run hot.
Closing the firebox door starves the fire of O2 which is a surefire way of causing nasty tasting smoke.

 

[Paulie Walnuts 440]

Just shovel embers in there and call it a day..the purest heat and flavor you'll get. I see Rodney Scott do it in his pits Hahahahaha