Favor please. measurement of FB to CC opening with a commercial tune plate in place

[Tallbald]

I fabbed my own reducer plate to lessen the opening between the FB and cook chamber on my OK Joe Highland and direct smoke under the tuning plates. Had to guess the amount to reduce and went with about 1/2 the factory opening. I judged by studying other folks photographs.
Sometimes I would like to be able to raise the CC temp to 300 and have some trouble reaching that temp even with FB drafts open all the way. The wood may not be completely seasoned absolutely dry so that may be a contributing factor. But sometimes I wonder if I closed off the opening between FB and CC too much. If I had a real measurement to go by I could maybe address the problem.
Thanks. Don.

 

[SonnyE]

My goodness Don, I read halfway through your post trying to figure out CC-Cooking Chamber, a FB-Fire Box.
I'm glad I visited your post, it was educational for me.
I have nothing to offer. Other than Damp wood, damp fire. And that can be very frustrating.

Otherwise, I learned the hard way about gathering firewood in winter. No leaves on the Poison Oak.
I got the worst case of Poison Oak ever! I itched in places I couldn't scratch.

But I know if you keep trying, you will succeed!

 

[daveomak]

The numbers below will work... Maybe your exhaust stack is too small diameter... or, could be you have too many air leaks....

Calculations for a standard design, reverse flow smoker..

Gallons X 231 = volume in cubic inches.... Sometimes the tag, in gallons, reflects a 20% air space for expansion....

Volume of the Cook Chamber.... Use the Inside Diameter of the tank...

Diameter X Diameter X 0.7854 X Length = Volume in cubic inches

Volume in cubic inches X 0.004 = FB/CC opening in square inches

 

[Tallbald]

Thank you both. I understand the abbreviation thing. It took a goodly amount of time for me to decipher them when I first joined. I still have to refer to the translation sticky sometimes. I thought WSM was a water smoking something for the longest time. I'll redo calculations for my smoker soon. maybe I need to open up the cook chamber to firebox opening a little.
My woodpile is a bought, delivered and stacked couple ricks of hickory and oak. $65 a rick each. Supposedly seasoned but still feels "heavy" somewhat.
Thanks again folks. Don.

 

[Tallbald]

Thanks. I did the math, and the opening should be like 29 square inches. Mine is at 31 inches square, so I can now investigate other causes. Don.

 

[daveomak]

Air leaks screw up the natural draft, real bad.....

 

[Tallbald]

Yes I read about the air leak issues early on. I bought gasket material for the CC and FB, food safe BBQ silicone caulk and installed two toggle clamps to tighten the CC lid like so many folks I saw doing on youtube. Seems to work pretty well so far. I do get a smoke leak out the drain hole where moisture drops into the bucket, but things are mostly sealed pretty well. I've begun to think it's just incompletely dried hickory, because last evening as the wood turned to just a pile of glowing red coals, the heat did spike to 300. Live and learn I reckon. Enjoying the journey still. Thanks everyone. Don.

 

[daveomak]

If you get smoke out of the drain hole, I'm thinking your exhaust stack is too small a diameter or not tall enough to create a good draft... Pictures would help.... Dave

 

[Tallbald]

Dave here's a photo of my modified stack as posted in an early thread I made with my Highland mods. Trouble for me is the factory chimney measures, I seem to remember, 3 inches in diameter. Sadly, that's something I cannot change because of lack of equipment (or cash flow to pay for same). I did though extend the stack 4-5 inches with a piece of stack from another smoker to hopefully increase draw, and add a semi-permanent cut bread loaf pan duct of sorts to lower the stack intake close to the cook grid to lower smoke exit level close to the grid. Essentially increased the length to about 30 inches including the duct. I think I'm stuck with the stack (that sounds like some sort of advertising slogan). Don.
Stack extension:

CC grid extension duct:

 

[Rings Я Us]

You would think that after millions of these smokers have been made over the years and people have been using them , that they would sell something that worked with very minimal extra modifications by the purchaser. I see this is not the case as far as the Oklahoma Joe style smoker is concerned.

 

[Tallbald]

I agree. I guess though some manufacturers target consumer is not a dedicated smoker but rather an occasional smoker who wants to try their hand. I was "that guy" 20 years ago with my first offset smoker (now it's a shortened modified patio burn thing for logs that I can safely shut the lid on and go to bed at the end of the evening). I tried a turkey once back then had bad results and never tried again until last summer. The OK Joe pleases me in general though mods were well within my skills and finances, and was priced at what folks like me can afford. Works OK as it came from the factory, but tweaking it makes it better suited to my wishes. Don.

 

[daveomak]

Thanks Don... You've done a great job sealing up the door and probably the rest of the smoker...
Are those tuning plates I see inside the smoker ?? I don't see much of a gap at the end of the smoker, under where the exhaust stack it... Perhaps, just guessing now, there isn't enough gap in the spaces of the tuning plates for adequate air flow... Try removing the last tuning plate... the one under the exhaust stack... What you can expect from doing that, better air flow through the Fire Box and through the smoker.... The plates may or not need adjusting after that is done.. Regardless, keep at least a 5" gap at the end so air flow is not restricted...
Doing all that, you should see a reduction in fuel usage.. An overheated FB wastes fuel... You should see even temps, or close, inside the smoker.. if you still think improvements should be made, scrounge up some 4" exhaust material and a 90 deg. elbow... Then we can work out how to cut a 4" hole in the end of the smoker..