00;00;00;26 - 00;00;20;24
Speaker 1
If temperature control on your smoker drives you crazy. This episode's for you. Hey, barbecue nerds! Hey, welcome to the podcast. I am. This podcast is for folks who don't just cook barbecue. They nerd out on it.

00;00;20;26 - 00;00;50;28
Speaker 1
Here. We break down the fire and the science and the secrets behind great barbecue and. And now here's your host on the barbecue pit, engineer Frank Cox. Hey, welcome back, barbecue nerds. Frank Cox here. I'm known as the barbecue pit engineer. And today we're kicking off season two with a foundational topic how fire actually behaves inside your smoker.

00;00;51;01 - 00;01;31;11
Speaker 1
Because once you understand this, everything in cooking barbecue becomes easier. So if you're new to cooking, barbecue, or pit mastery in general, you're probably experiencing some issues like these temps swinging all over the place. Sometimes you might feel like you're fighting the fire instead of running it. Your temperatures aren't changing when you do things like change dampers or add wood to the fire, or take wood away whenever you add wood to the fire, your smoke's going super dirty and you've likely heard things about white smoke or dirty smoke, and you've got a lot of questions about that.

00;01;31;14 - 00;01;56;20
Speaker 1
Something else you might have faced is like one side of the pit hotter than the other. We've all faced things like this, so believe it or not, a real quick story. I wasn't always known as the barbecue pit engineer. As a matter of fact, I was a complete novice when I started cooking barbecue. You know, growing up, my mom was always roasting hot dogs with sticks over coals and, and, you know, limbs from the yard and stuff like that.

00;01;56;20 - 00;02;12;25
Speaker 1
And we really had a good time with that. But it didn't come naturally to me. I was actually the guy, if you had to think about it. I was the guy that was running around the cooker in a panic when the flames went out shooting charcoal lighter fluid all over the coals to try to get the flames to come back.

00;02;12;27 - 00;02;37;28
Speaker 1
You know, even though. And this makes it even better. I was a refrigeration guy. Like, I started when I was 19, in the refrigeration service engineer trade. And I was working on supermarket stuff, like really high tech, very complex systems. I started when I was 19, and you learn a lot in that trade really fast, especially when you're working on big, heavy, crazy stuff like that.

00;02;38;01 - 00;03;06;20
Speaker 1
And I had to learn how he moves and things like that. Well, that did not help me when it came to live fire combustion like coals and sticks and things like that. So, you know, growing up there was a lot of in, in the refrigeration trade growing up and also beginning my career as a refrigeration guy. There was a lot of no dumb moments, you know, like you, they're not book learning things that you learn early on.

00;03;06;22 - 00;03;32;03
Speaker 1
So anyway, you're probably a lot like me growing up. Not maybe not growing up in barbecue, but learning how to cook barbecue. And if that's true. Just know you're not alone in this. Everyone goes through this, and fire is is not unpredictable. Could just be that. We just haven't been taught how it works yet. So my goal in this episode is to help you kind of learn how heat moves.

00;03;32;06 - 00;04;05;14
Speaker 1
You know, the episodes titled How Fire Behaves. But the the real important part about it is it's not really all about fire. Fire is where our heat energy is created, and that heat energy is what we carry through the pit with air, right? But it all begins at fire. So let's talk about how this actually works. And just so you know, in full transparency, I do have some bullet points here because I'm not smart enough to do this in one big take without mess ups.

00;04;05;17 - 00;04;37;04
Speaker 1
So hopefully my podcast editor is smarter than me and he can help me with this. Actually, Brad is amazing by the way. So here we go. Let's jump right into this. So heat moves in three ways. You know, you've probably heard this before in eighth grade science. And the funny thing is, is that most of the no dumb moments that I've ran into in my life were things that someone tried to teach me in either elementary school, junior high, high school, and and the like.

00;04;37;06 - 00;04;59;07
Speaker 1
They're they're typically things that I wasn't paying attention to that I should have been paying attention to. So let's talk about how does heat move? Heat moves in three ways. Radiant heat, which we can almost say it's omni directional, which means it moves in all directions and it is not carried by air. Radiant heat is actually omni directional.

00;04;59;07 - 00;05;25;15
Speaker 1
It moves line of sight. And it's what a lot of people refer to as infrared. You know, that's a that's another spectrum that radiant heat operates in. So it's hotter closest to the heat source, which in our situation is typically a coal bed, not the flame. So the other kind of heat is convective heat. Convective heat. We've all heard that like a convection oven or an air fryer these days.

00;05;25;17 - 00;05;50;03
Speaker 1
Pretty much what we're doing is we're moving the heat from the heat source with air. And that air is is carrying it through whatever we're trying to cook in, like an oven or a smoker in our case. And the other kind of the third kind of heat is called conduction heat or conductive. Now this is direct heat source usually through radiant heat.

00;05;50;07 - 00;06;16;14
Speaker 1
Honestly, if we had to really get down to like reverse flows and stuff like that is the a piece of metal typically in our world is going to absorb the heat. If you're cooking on a gas grill, it's likely that you've got something with a ceramic plate in it or something like that, and the heat is going to travel through whatever that conductive surface is, where it is stored up, and then it will transfer directly into whatever is sitting on it.

00;06;16;16 - 00;06;37;04
Speaker 1
Whenever you get into like electric elements or reflective heat, like on, ceramic heaters and stuff like that, of course we have to heat up the plate, the ceramic plate or the steel plate or whatever that is first, and then it can radiate out of it, or it can transfer directly into whatever is on it, such as a sear plate with a steak.

00;06;37;06 - 00;07;01;20
Speaker 1
So, you know, that's that's the three ways that heat actually is transferred. Now how air flow works. And I've talked a lot about this. If you want to know more about my background and you've never heard my name before. Go over to YouTube's is a great place to start. Or if, since you're on the podcast channel already. Anyway, go over to Smoker Builder Podcast on the airwaves here.

00;07;01;22 - 00;07;27;05
Speaker 1
Or if you go to the YouTube's Go to Smoker Builder on YouTube and you can see a basically more than a decade, probably almost two decades of content out there that I've been producing since about 2010 about this kind of subject matter. But anyway, air is one of my favorite things to talk about because, like, I can almost see the air how it moves just because of the experience in the trade.

00;07;27;07 - 00;07;56;22
Speaker 1
And so how air flow actually works is we have to, first of all, consider that a fan can blow it. And when you hold your hand, do experiment with me real quick. Hold your hand in front of your mouth and blow on your hand like that. And what you'll notice is, is that air moves like this is one of those no dumb moments from eighth grade science class where we learned that air has density and mass, and we can actually measure it right through different means.

00;07;56;25 - 00;08;20;07
Speaker 1
Some means we have to calculate. So the important thing about that is that hot air, whenever you heat an air mass, it loses density. When you cool down an air mass it gains density. That means it's heavier. So what happens is as we heat an air mass, it rises. This is where we start talking about draw. We're going to get into draw here in a little bit.

00;08;20;07 - 00;08;50;04
Speaker 1
I don't want to get rabbit trail yet, but that's probably one of the single most misunderstood terms in pit operation in our industry. Mostly because, you know, we just haven't learned what it is. So hot air rises. This actually pulls your fresh air in through the intake. Keep that in mind. Now the intake is where we start bringing air into our smoker.

00;08;50;06 - 00;09;19;05
Speaker 1
The intake is like a damper typically on the firebox door or something like that. The air comes in, it's cooler, it's oxygen rich, and when it comes in, it goes directly into the fire. Now this is where the fire triangle comes into play. Some of that oxygen is consumed out of that air mass for combustion purposes, but the rest of it is actually the medium which through which we are carrying the heat from the fire to the cook chamber.

00;09;19;08 - 00;09;45;29
Speaker 1
So we're going to go in from the intake. We're going to go across some kind of a coal bed in a fire, and then that air is going to continue to run to what we call the cooking chamber, which is where you're putting your meat, typically on a cooking grate. You could be hanging it also. Then it's going to be drawn into the stack, which equals that completes the draft scenario where we're pulling air in, it's getting heated and it's also keeping the fire running.

00;09;45;29 - 00;10;16;07
Speaker 1
Then we're carrying the smoke and other products of combustion such as CO2, moisture, smoke particles, particulate from whatever we're burning, etc. all of these things have an impact on how well our smoker is burning. Now, in order for a fire to burn clean, that fire needs to be oxygen rich, right? So if it doesn't have enough oxygen, that's one thing that can cause your smoke to be dirty.

00;10;16;10 - 00;10;36;15
Speaker 1
That's that dirty smoke is what's carried through the pit. Whenever we say you got dirty smoke or white smoke coming out the stack, that's what we're talking about. So a couple of things that will cause airflow to not be clean is like your logs piled too close to each other. Sometimes we do this on purpose. That's called a bundle fire.

00;10;36;17 - 00;10;55;28
Speaker 1
But most of the time you need to get adequate airflow all the way around. Whatever is on flame or on fire. The coal bed is where all the radiant heat comes from. So when we start to put our logs too close together, that'll suffocate. We'll get more into that here in a little bit. Ash buildup is something else that most people are concerned with.

00;10;55;28 - 00;11;19;22
Speaker 1
Now, I'll tell you first hand, ash isn't always a problem. Ash can actually help you control your fire or your temperature in the in the cook chamber. Now, the other thing is, is the quality of your wood. Quality of your wood actually has a huge impact on how clean your fire burns and how well your smoker is heated by the air, by the hot air that's coming from your fire.

00;11;19;24 - 00;11;41;20
Speaker 1
So keep all of those things in mind as we get into this. Now, when we're talking about how heat moves, different kinds of smokers need different kinds of heat. Of course, this is another one of those no dumb moments that I didn't realize getting started. In this case, we're going to talk about two different kinds, which are the most popular right now.

00;11;41;22 - 00;12;11;06
Speaker 1
We've got direct heat smokers, which you'll hear us talk about. The smoke slinger pits from time to time, which in my opinion are the best ones on the market. I really love them and it was an unexpected thing for me. But Direct Heat is now like my go to. I just absolutely love it. But offset smokers and you can see in my history on the smoker Builder channels, YouTube, Facebook, smoker builder you old websites that were forgotten about that have now been deleted.

00;12;11;09 - 00;12;40;19
Speaker 1
Offset smokers is where I cut my teeth and reverse flows and stuff like that, which reverse flow is just a different type of offset basically. But direct heat pits where they shine is more radiant heat. However, we can still in the smoke slinger use it with convective heat as well. So but the most popular thing you'll hear people talking about with direct heat pits is the radiant heat that you're cooking with direct over the coals, so to speak.

00;12;40;22 - 00;13;03;11
Speaker 1
In this kind of a pit, you're going to get faster cook times, you're going to get faster reactions whenever you're messing with dampers and stuff and you know, your coal bed is the most important thing. Like I said early, one of my biggest no dumb moments was when I was running around the smoker squirting lighter fluid all over the coals, and I didn't realize the flames weren't actually doing the cooking.

00;13;03;14 - 00;13;29;04
Speaker 1
That was a no dumb thing for me. Big time. Anyway. Offsets. We'll get into that real quick. Offsets absolutely rely on convective heat. As a matter of fact, I'll tell you a story here in a little bit about why, how and how I learned a big, no dumb moment of of how important airflow is in a smoker compared to radiant heat in the offset smokers.

00;13;29;07 - 00;13;51;08
Speaker 1
So anyway, we have to have convection because we have to travel horizontally over the length of your pit with that heat in our air. Right. So the air comes in the fire in the inlet, it goes through the coal bed, the firebox transfers into the cooking chamber. And then that's where we actually start moving the air horizontally towards whatever we're cooking.

00;13;51;08 - 00;14;26;09
Speaker 1
Now, if you've got a big thousand gallon pit or you seen one that cooking great is at the center of the cooker, and that air has to travel 16ft. Yes, it's 16ft, typically from the firebox to the smokestack. And we have to be able to carry that heat evenly throughout that cook chamber. So to get a fire running properly in the correct size, firebox and heat enough air that can carry that air all the way through the cook chamber to the stack and keep it even within a certain temperature difference.

00;14;26;09 - 00;14;52;14
Speaker 1
Let's say 5 to 10 degrees is almost a miracle, honestly. So it's all about how the pit is designed, that we can actually do that. And we'll get into that a lot on our podcast here in this episode a little bit, but future episodes as well. So the other thing is, is that when you do get a smoker, like a 1000 gallon offset dialed in, that thing has a very smooth learning curve.

00;14;52;16 - 00;15;18;09
Speaker 1
The problem is, is that we don't go into it understanding how the heat is transferred into the cook chamber, and how much air is actually required. As a matter of fact, most of us that learn how to cook on a thousand gallon offset have cooked on offsets that were not necessarily designed properly, in my opinion, but that has a huge impact on how smooth that temperature curve is throughout the pit.

00;15;18;12 - 00;15;42;18
Speaker 1
Now, the other thing is, is that the smokestack is actually like the rhythm section in this smoker where it's placed, how big it is, how you interact with it as far as a damper goes. And dampers are a critical thing. On getting an offset to work properly. If you have a cooker right now with a stack that is just wide open, there's no way to shut it down.

00;15;42;20 - 00;16;05;16
Speaker 1
This one thing can change the way your smoker works. Believe it or not. So anyway, why does this all? Why does all of this matter? Like why understanding you know, the how heat and how smoke and how fire behaves around the correct amount of air and how it behaves in your pit whenever you have, properly designed pit.

00;16;05;18 - 00;16;28;22
Speaker 1
Why does all this matter? Well, first of all, we want to have predictable cooks. That's the big thing right there. You know, less frustration when you're running the smoker. We want this. We got into this not because we wanted to become eighth grade science teachers. We got into this because we wanted to cook great barbecue, and we wanted people to brag about how good our food is at it, ultimately.

00;16;28;25 - 00;16;51;05
Speaker 1
So ultimately, we we want less frustration when we're interacting with this fire and this smoker. And also understanding this will help you stop reacting to what your pit does and actually puts you in the driver's seat to where you can actually manage the outcome of how your smoker runs and the quality of the food that you're going to get.

00;16;51;07 - 00;17;20;23
Speaker 1
So let's get into some actionable steps here. Now, remember, as we go into this, we're talking about how the fire naturally wants to behave in your smoker. That's the key to all of this. We also want to clearly understand that the fire is what's burning down the wood, and the wood is actually what becomes coal bed in any smoker where you're burning sticks or charcoal.

00;17;20;26 - 00;17;46;27
Speaker 1
The coal bed is where 100% of the most important heat is coming from in your pit. So controlling the size of that coal bed is very important also. So here's how we can flatten the curve and get to get in the driver's seat with any smoker, be it a direct heat smoker or offset smoker, the first thing we got to do is build a real coal bed.

00;17;46;29 - 00;18;23;07
Speaker 1
Important components of a coal bed are some kind of embers. Those embers could be created through lump charcoal. That's how I typically start most of my fires is I'll get a good pile of lump charcoal sometimes. On certain occasions I might use briquettes if I want to get a longer, more consistent burn. But you're going to have a higher ash content with briquettes, so be aware of that lump, however, is actually what is being created whenever the wood is consumed in a fire and it becomes coal bed you actually wind up with already lit lump.

00;18;23;07 - 00;18;43;02
Speaker 1
Charcoal is what's in the coal bed. And as actually, I suppose now I'm saying that when we talk about the coal bed, we're not talking about the wood that's on fire. We're talking about the actual pieces of coal that are fully engulfed in flame. That's the coal bed. And you want to take your time with this, getting it established.

00;18;43;04 - 00;19;09;14
Speaker 1
Like if you're cooking on a offset smoker, especially a bigger offset smoker or one that's built with like quarter inch thick walls and stuff like that, you need to take your time getting that coal bed established. Give yourself an hour, because if you're cooking on an offset, your goal is not a fast cook. However, you'll hear some guys talk about hot and fast, but offsets really shine when you get into that less than 300 degree range.

00;19;09;16 - 00;19;34;01
Speaker 1
So you're going to want to take at least an hour getting that coal bed established. If you want to see me physically do that, go to our YouTube channel and look up some of my videos on Smoke slinger.com or the Smoke slinger YouTube channel. Smoke Slinger pits. You'll see where I'm actually showing how to light a fire in the Liberty 94, which is our offset, and that'll give you some visual into this.

00;19;34;04 - 00;19;58;15
Speaker 1
Once that coal bed is fully like engulfed, like it's starting to turn more than salt and pepper. It's more salt and pepper color, which is like a gray or white more than it is black. Then you can start to actually add wood to your coal bed and your fire. Once you, because you want to get as much oxygen to that coal bed as possible so that it can get hot.

00;19;58;17 - 00;20;21;19
Speaker 1
One more thing to point out about a coal bed and managing your coal bed. Is that the only part of the coal bed that is actually hot is the part that is exposed to oxygen. So if you're cooking in like a firebox where you've got like a the bottom of your firebox is round and it's dished out, and so you've got this pile of charcoal in there.

00;20;21;21 - 00;20;42;11
Speaker 1
Once that coal on the top gets fully lit and starts to ash up, it starts to pack a little bit tighter in there, and you're not going to get as much oxygen flow down underneath of that first layer. This is good and bad. If there's not enough exposed charcoal on top, your coal bed is not going to make enough heat.

00;20;42;14 - 00;21;09;11
Speaker 1
If there's too much exposed, then it's going to be too hot. So this is how we can kind of pack everything together a little bit and manage a bigger coal bed for a lower temp situation is to kind of crowd it a little bit and prevent as much air from getting around the pieces of charcoal. It's the surface area that's exposed to oxygen that is actually creating the hottest and the greatest amount of BTUs that heat the pit.

00;21;09;14 - 00;21;31;21
Speaker 1
So once we get all of this magic happen and we've got a proper coal bed established, we've started to add our wood. Now we want to manage that that fire smartly. And here's how we do that. The biggest thing, the smaller the pit, the smaller the pieces of wood you're going to need. The bigger the pit, more wood is going to be required.

00;21;31;21 - 00;21;50;28
Speaker 1
This does not mean bigger pieces in my mind. While your pieces may be a little bit bigger, you're just going to have to add more wood to it. Now, adding wood to an offset smoker. If you have experience where you think that your pit is a wood hog, it's likely not the wood's fault. Where maybe some of it is.

00;21;50;28 - 00;22;10;17
Speaker 1
It could be too wet or piled too close together, but most of it is. We just didn't get the coal bed established properly. We don't have a direct path for the air coming in the inlet to get as fast as possible to that coal bed. That's that's the biggest probably problem with this. So now we're going to manage our fuel smartly.

00;22;10;20 - 00;22;33;17
Speaker 1
We're going to add smaller pieces more frequently. Don't toss. This is a big one. Don't toss big cold logs into your fire. Instead what you're going to do is preheat those logs. If they're bigger and split them down in size. You're probably asking right now, what is the ideal size piece of wood for any pit that I personally own?

00;22;33;17 - 00;22;57;08
Speaker 1
I typically use something between a two and a half to three inch diameter piece of wood, and diameter is a triangle shape. It's just it would fit inside of a piece of pipe that's like 2.5in diameter or three inches diameter. That's the ideal diameter of a split, in my opinion, and you're going to want it to be around 12in, probably on bigger pits and eight inches on smaller pits.

00;22;57;10 - 00;23;15;28
Speaker 1
Now, if you've got a box store style pit like an Oklahoma Joe or something like that, that's thin and it's a lot smaller, you're going to have to cut that in half. So you're going to want to be around that one inch to inch and a half size, and you're going to have to add less wood more often if you have a smaller pit.

00;23;16;00 - 00;23;36;11
Speaker 1
And anyway, on bigger pits, you're going to add more consistently the same amount of wood. So as we get into there, don't toss big cold logs into your fire. Make sure that you're preheating them somehow. I like to put them up on top of the firebox, for instance, or even in the smoke slingers. We will light on the full size.

00;23;36;11 - 00;24;02;19
Speaker 1
We'll light one drawer on the left and we'll put our wood in the right. Draw not on fire, and we'll let that just basically sit in the oven and heat up. You know, that's a great way to do it. The other thing you got to do is you got to keep your airflow consistent, leave your smokestack open at the beginning, makes make slow, small adjustments as the cook goes on for the first hour, you're not going to get excited and close that stack down.

00;24;02;21 - 00;24;20;08
Speaker 1
You're going to wait until this thing is in what I call cruise control. Then you're going to start to choke that that smokestack down. Because like I said, it's going to take time to get that coal bed established. You don't want to close that smokestack so much that you start to choke out the oxygen flow to that coal bed.

00;24;20;10 - 00;24;41;24
Speaker 1
That's a very important thing. Like I'll run my big offsets with that smokestack damper at the very outlet of the stack. I'll run that damper probably 50 to 80% closed at times, but that's not happening until I get a properly established coal bed. The other thing you can do is watch the color of the smoke throughout the cook.

00;24;41;26 - 00;25;01;23
Speaker 1
Now, don't get alarmed when you put a fresh log on, especially if that logs not pre-heated or it's not really seasoned very long. Don't panic and like open everything wide open whenever you first put that log on or throw a bunch of charcoal in on the coal bed, just let it clear for a minute. It's got to heat that thing up.

00;25;01;25 - 00;25;26;21
Speaker 1
Once that log gets hot and starts to combust, that's that's like I don't remember the temperature, but it's pretty warm. Once that wall gets warmed up, it's going to actually start to change your color to blue. That's when it's going to actually happen. But if you start to get a cloudy white or gray smoke that is consistently that color, then you're going to have to do something with your fire.

00;25;26;23 - 00;25;47;14
Speaker 1
A couple of tricks you can do is let more air get in between your logs by spreading them out. Elevate your logs over the coal bed a little bit. Maybe your logs are blocking airflow to the top surface of the coal bed. Spread your coal bed out a little bit so that you get more surface area of the coal bed exposed to oxygen.

00;25;47;14 - 00;26;08;07
Speaker 1
That's why you'll see us kind of take a shovel on a big pit and spread that fire left to right. If it's if your smoke is blue and you can't control temperature, that's when you would start to pack it down. And the ash could actually be your friend in that scenario. But then, you know, the other thing is it's like we're going to pay more attention to the smoke and the flame.

00;26;08;09 - 00;26;36;01
Speaker 1
Then we're going to pay attention to temperature. The temperature on the on the thermometer is is only a point of reference. If that thing is within 20 degrees left or right of the dot of the number you're on, you're probably not going to have a noticeable difference in your barbecue if you just pay attention to that, to what the pit wants and what your food looks like now, you can always raise temperature later in the cook and finish something off.

00;26;36;03 - 00;26;53;08
Speaker 1
But as you'll learn in these in upcoming episodes, we're going to talk about some meat science and stuff like that and what it takes to get proper render and things like that. We're going to have to have some time involved there. We can't rush this, so don't freak out about what the needle says. This isn't a pellet smoker.

00;26;53;10 - 00;27;21;14
Speaker 1
Ten degrees down or up isn't going to make a bit of difference in how your cook is going. Last thing I'll say here before we wrap up is keep it simple. Just remember, coalbed is the most important heat source. Airflow is what's going to transfer that heat into where we're cooking. And a clean burn is what's going to give us that great barbecue flavor and help us build the perfect bark.

00;27;21;17 - 00;27;48;09
Speaker 1
So anyway, I really like doing this podcast. I'm going to be doing episodes like this coming up as as we go. Hopefully every Tuesday morning at 5:00 am central time is when every episode should publish. So if you're on your way to your morning workout, be sure to catch it. You can listen to this exclusively on iTunes, Spotify, and any other podcast platform.

00;27;48;17 - 00;28;10;18
Speaker 1
I'm not putting it on YouTube music because it messes up my YouTube channel, but you can still catch it on these platforms. And, you know, understanding the topics that we're talking about here will make your barbecue journey very fun. You'll be able to spend more time having fun, hanging out with other barbecue nerds, and focusing on great food, which is why we're all here.

00;28;10;24 - 00;28;32;01
Speaker 1
We don't want to be eighth grade science teachers lol. So hey, real quick, if you enjoyed this episode, please please please give me a rating if you don't mind, click that review button on whatever platform you're listening to and give me some honest feedback. Words matter, not just stars. I want to know how you feel about the podcast.

00;28;32;03 - 00;28;55;05
Speaker 1
Rule number one of this podcast is find other barbecue nerds near you and invite them to the Inner Circle. That's what this is. You're all barbecue nerds because you listened to this entire episode. That's how I know. And then, you know, go do something nerdy. This way you can use the hashtag barbecue nerds, BBQ nerds. Till next time, keep your smoke thin and blue and I can't wait to bring you another episode next week.