Smoke stack help please

[Ads1080]

Hi, im Adam from the UK

Please could anyone help me out with my smoker that ive recently finished.
Im now thinking my smoke stack is to long and the CC is collecting too much smoke and isnt being exhausted quick enough because of the distance it has to travel up the stack?

Currently my smoke stack is 4" dia x 39" length. Is this to long or what should it be?
I have been considering shortening by 15" and bringing it down to two feet long which will keep the top of the stack just above my head height and stop the smoke smacking me in the face.

The CC is a 42"x14.5" propane tank (biggest i could get in the UK) FB is 19"x14.5.

FB to CC opening is 9" x 3.5" 
FB air intake is 7" x 3.5"

I have
Many thanks for any help. I appreciate any suggestions.

Thanks
Adam

[towtruck]

Running the numbers through the calculator it appears your stack needs to be just under 13" long. Your throat is a tad over sized but does not look bad.

Whack that stack off and try it out!

[Ads1080]

Thanks for the reply.

When i built the smoker i just thought 4" minimum and longer the better, greater the draw.

Now running different calculators and searching through thread after thread im not thinking the same anymore. im getting from different calculators anywhere from 8-13". Im nervous of cutting it as short as that.


When you say throat, is that the opening between FB and CC? I attached a photo of what is looks like (the shape)

The smoket is standard offset but added tuning plates to try and even out temps left to right.

Thanks
Adam

[Dirtytires]

run the calculator....all your numbers need to be in line for a properly running pit.

[Big T]

Where is your stack located on the CC ? How are your tuning plates set up ? Post some pictures of the smoker, inside and out and that may help to identify the issue.

[Ads1080]

Smoke stack is inline with the cooking rack the horizontal section of the smoke stack is 2.5" to the inside of the 45°



Tuning plates set up so i get even temp left to right and are at the same height as the top of the FB to CC opening.

Thanks for all the replies.
Adam

[Big T]

What are the main issues that you're having with your pit ?

[Dirtytires]

You already know that the stack is too high. Many members have also had much better luck with the exaust at the very top of the cook chamber. The lover opening tends to trap smoke in the top of the pit which then can drop soot on the meat.

[Ads1080]

Thanks for all the replies.
I'll chop the stack down a bit on the weekend and see how that goes. From the calculators i think im in the ball park with with everything else.
My only issue is i think the cc is holding onto the smoke too much instead of exhausting it.

Thanks for the help and suggestions
Adam

[towtruck]

You could add a stack out the very top of the chamber that is the right size and plug the current stack to see if that improves the flow.....it's a little more work but may do the trick. I would try chopping what you have first and go from there.

[Big T]

I also would recommend moving the stack up higher on the CC and cutting it to the recommended length.

[Ads1080]

Does look strange with the chopped stack.

The smoker doesnt draw as hard now, though the fire remained burning nice with FB inlet half closed and smoke stack damper wide open.
I removed a tuning plate and repositioned a few and i think im back to even temps left to right. Smoke seemed to be clear, thin and blue for the two hour test yesterday.

Thanks
Adam

[ajfoxy]

Looking good.

[Big T]

[towtruck]

Nice!

[Dirtytires]

Small steps....try it for a while but you might need to do a bit more work in it.

[Ads1080]

@Dirtytires thats all the fun in it, right?
Always looking to improve things. What else do you think might need some attention, based on my dimensions etc?

Thanks for all your help
Adam

[Dirtytires]

Besides mounting the stack at the top, I’d probably run it a few times then let us know what is happening.

Double check your numbers. You mentioned you tried several different calculators and got different numbers. Best bet is to use one theory for all your numbers. Can’t vouch for the other sources but the ones here work....you just have to trust it.