keeping the temperature up in the smoker

[Shawnt]

Hello Everyone
Well I did a little test run with the smoker tonight and didn't have much success. (I'm a virgin) lol'.
Ok here is what I built,80 gallon tank with a 24" square fire box. I'll post some picks... the fire grate is about 4 inches above the bottom of the fire box and I made the vent door below the grate. I'm thinking of making another vent door above the grate for optimum control but not too sure if that would be necessary at this point. the stack is a 4x3 in. Oh..and it is a reverse flow. .. I put some charcoal in and lit it up. I got the temp up to 150 and then started adjusting the doors to try and get a feel for the operation of this smoker but I just couldn't maintain the temp. I'm thinking one of the problems is that I didn't use enough charcoal. I'm sure the firebox is not totally air tight but i'm thinking I should still be able to maintain a steady temp. I know I have to experiment more but any points would be a big help at this point.
Here is a cpuple picks of the build if that helps. Thanks.

[Gizmo]

Shawnt that's a perty good looking outfit there and I don't know if this will help but my first impression is that it can't breathe well enough.

When I was a kid I remember my great uncle Raz telling me that if you aint in charge of the airflow then you just aint in charge. He was referring to dark fireing tobacco in a tobacco barn but the principal is the same. Do what you can to seal it all up so that air is forced to go where you want it to - through the cook chamber and up the stack.

Was 150 all you could get out of it?
How long did you wait for temp to build?
What is the total square inches of baffle gap at the far end?

If you've got a couple hours try this:
Open your stack 100%
Open your draft to 8 square inches
Light 2 charcoal chimneys at the same time
When they're all white pour them into the center of the firebox grate and push them into a pile.
Pour one more chimney of fresh unlit briquettes gently on top of them so they are all touching.

Close it up and start a clock set to straight up noon.
Record the time/temp every 10 minutes for 2 hours and don't adjust anything.
Once the temp stays about the same for 2 readings - close the draft to half and note it.
Post your times/temps back here with a picture of the draft.

Or you could call Frank and have him calc it and solve the mystery real quick ...

[Shawnt]

Rick Thanks! I'll do that and let you know how I make out.

[Frank_Cox]

Nice looking build shawn! here are a couple things I noticed.
For starters you could check out your stack. it looks to me by taking a quick look at the numbers it is too short. i recommend you change to 4" and make it the same length as you have now. your firebox is much larger than needed so the stack needs to be larger than it is to balance it out. I don't have your actual dimensions of your tank so i just used the 80 gallon number you mentioned earlier. If you want you can always call me up and I would be glad to help you out in more detail!

[Gizmo]

I think Frank meant 4 inch ROUND ...

[Frank_Cox]

yep sorry....

[Gizmo]

...it's early and I don't DO mornings well ...

[alleyrat58]

That's a good looking rig you got there! I agree with Frank your stack could be a little small. The other thing that comes to mind is to just keep lighting fires in there when you have a few hours here and there. You will learn the idiosyncrasies of the cooker and sometimes I think you just need to light a few fires in order for the cooker to really come into its own - at least that is my experience. The other thing - similar to Rick's idea - is during warm up - feed that fire in small increments every 15 minutes. That will allow your fire to continue to build without choking out all the air in the firebox. If you really want to get some air in that box, crack the door. That will tell you if you need to add another inlet or not.

[Frank_Cox]

If you really want to get some air in that box, crack the door. That will tell you if you need to add another inlet or not.

exactly, and also this is a good test to find out if your draft problem is with the firebox or the stack/ baffle plate gap. if you crack the door slightly the fire will have more air which will make the fire hotter, if the cook chamber temp does not go up, you have a problem after the firebox. on the other hand if it does, you more likely have undersized air inlets. also if it goes up but does not last long your firebox may be undersized.

[Shawnt]

ok guys I performed the burn test last night and here is what I came up with. I started at 4:40
4:50-165
5:00-195
5:10-205
5:20-240
5:30-250
5:40-250
At this point I closed the draft 1/2 way(draft full open is 11"x3")
5:50-225
6:00-210
6:10-200
6:20-185
6:40-170 At this point the charcoal seem to be used up. I'm using chunks! I'm think temp stability could have been achieved if I had add some more charcoal?
I do agree with alleycat that I do need to try this a few times to get a feel for the smoker. I'm going to try it again tonight. I will also mention that during the test I had the stack vent cover fully opened the whole time.
I'm going to tray it a few more times and if I do have problems I'll give Frank a call!! I think I will be lining the firebox with fire brick also so I can extend the smoking into the cold months.

Let me know what you guys think about the results!
Thanks

[Gizmo]

MY BAD! - I APPOLOGIZE

I went back and checked my post and I MEANT to say "when the temp stabilizes close the STACK to halfway..."

Depending on how well sealed everything is, the stack does 2 things:
1) It has a big effect on how efficient the draft is and thereby the range it will control.
Think of the stack as a rough control and the draft as a fine tuning adjustment.

2) It will sort of "stall" the heat from leaving and help the cook chamber build heat over time....

The goal is to learn where your draft needs to be to hit your target temp and all the fiddling with it should be done with the Stack at half open. That way when you know the sweet spot on the draft you will still have all that movement available to you to change the range your draft is working in. Like a different setting in the winter when it's only 10 degrees outside.

I'm a little confused - did you operate the draft at 8 square inches to start with or did you run half of the 33 (11 X 3) ?

You were in the money at one hour into it so it doesn't look like you'll have to modify your rig - just get to know it ...
If you're doing another test then add a #10 can of briquettes at the one hour mark (about half a chimney).

Everybody's got their own voodoo magic method - this one just seems to work for me ...

Again - I appologize

[The Czar]

Great....just great......now I am all messed up..thank alot Rick....

[Gizmo]

sorry

[alleyrat58]

Looks like you are doing good there Shawnt. Just need to figure out how hungry that thing stays once you are at temp. You might need to feed it every 30 or every hour, but if you keep feeding it consistently it will stay at temp for you. Getting up to temp in an hour is pretty good. Mine takes a full two hours to really get stable.

what Rick said. Crank your stack down to half, leave the draft full and see if she maintains temp on regular feeding schedule. Looks like she'll work...

[Shawnt]

Ok Guys! Did another test run tonight,last night rained,and had some great results!! I started with 2 chimmneys of charcoal lit up and another not. Temp came up nicely and hit 325 deg. I closed down the lower air draft and got a feel where I should be at as far as the opening goes. It took a while to get the temp. down,LOL!! the oposite of what was going on before. I was able to maintain 180-190 with no problem at all! The temp started to decline after about 2.5 hrs. because it needed some more fuel. I added a few pieces of birch I had laying around and the temp was back to 190 in very short order. I ended up adjusting the stack vent to about 2/3rds and the temp. never budged from 180. I'm very happy with the results thus far. I'm confidant I can now add some swine and take the leap!!lol. So Sunday I'm going to attempt a couple pork shoulders!! I really hope it turns out because I invited a few people over! LOL. Anyway I must say the help from you guys and this site has really helped this newby a lot.I still have tons to learn and know I'm on the right forum to get to where I want to be.
I'll keep you posted and if there is anything you feel I should know feel free to guide me along.
Thanks

[Gizmo]

I think I just heard an angel get it's wings!
Stick with it Shawnt - You got it on the ropes now ...

[Frank_Cox]

Sounds like your on the right track!
as a rule I add fuel about every 45 minutes or so. biggest thing to remember is stay ahead of the fire.... don't wait for it to die before you add fuel. another thing is watch my video and notice how i let the wood start perty good before i close the door. you will be able to avoid the heavy white smoke that causes the "too much smoke" issue (better known as soot)

here's the video.....

[Shawnt]

Smoker now painted. First smoke starts tonight!!! 2 10lb butts. Wish me luck! lol

[Gizmo]

Looks good shawnt - good luck!

[Shawnt]

Thanks Rick.

[rlmax02]

good looking piece. good luck with the cook!

[Smokeone]

Cant wait to see those butts!

[Shawnt]

Hello Everyone.
Well I did my first smoke a few weeks ago and the results were mixed! The guests said the pulled pork was good and they seemd to eat lots but I wasn't conviced. The ribs were way too smoky/bitter. Now I'm sure its a inefficient stack and Rick and Frank pointed that out first thing!! Now I have to say I used a sh@*t load of fuel to do that smoke,i'm not sure if thats normal!
I'm determined to master this smoker,lol!! So I removed the old stack and install a much bigger stack. 3.5"x7" I'll post a pick.
I did a little test run last night and the temp came up really fast!! ,I felt like a 5 year old a Christmas!!LOL!! I was able to hold steady at 225 for a lot longer than I did before so I'm hoping I won't use as much fuel. So tomorrow I'm doing 2 shoulders and some ribs. <a href="http://s1232.photobucket.com/albums/ff3 ... =005-1.jpg" target="_blank"><img src="http://i1232.photobucket.com/albums/ff3 ... /005-1.jpg" border="0" alt="Photobucket"></a>

[Shawnt]

Hello Everyone. Well I did my first smoke a few weeks ago with mixed results. the pulled pork was not bad says the guests but I wasn't convinced!. The ribs were very bitter!! Too much smoke I'm thinking. I think Rick and Frank hit it on the head!"stack too small" won't breath properly!!. So after all this work and money I've put into this smoker I have to get it right!! I removed the old stack and installed a much bigger stack. The old stack was 2.5"x3.5" the new stack is 3.5"x7.0". I did a test run with the new stack on Friday and I couldn't believe how fast the temp. came up!! Now the first smoke I noticed I used a crap load of fuel so I'm hoping I use less this time. It should be more efficient I'm thinking? Anyway thanks to Frank and Rick for your help. I'm smoking 2 butts as I write this. I'm hoping this turns out better!!

[Shawnt]

Stacks!!