help with new smoker

[Calenk]

I just recently received a custom built smoker. It's a really nice unit but I broke some of the 'rules' of the various calculators out there as far as dimensions go.

I've only done one cook on it so I'm not all that familiar with it yet but I feel like I was going through more wood than I thought I would.

Specs are as follows 5/16" steel. 16" pipe. Cook chamber is 40". Firebox is 21". Stack is 3" pipe and 40" long.

So the firebox is quite a bit bigger than the calculators state. I'm not sure how much that matters seeing as Workhorse pits go even bigger and say it's not an issue.

The stack is pretty long as I got him to leave it long so I could trim it down to the ideal length.

The stack exhausts higher up and not at grate level.

I guess my question is how much would should I expect to go through on a 6 hour cook? And how often should I have to be adding a split?

[Hawklaw]

is consumption the only concern? Otherwise it was drafting and holding even temp ok?

[Calenk]

Originally Posted by Hawklaw

is consumption the only concern? Otherwise it was drafting and holding even temp ok?

Well that I'm not sure as my old smoker was very different than this and its all I'm used to. Once I got it too temp it seemed to draft good. My splits had to be pretty small to avoid white smoke. I'm curious if shortening the stack would give me better draft but I'm hesitant to cut it down.

[KClandcruiser]

Shortening the stack will decrease draw. With a pit that size, I'd imagine your optimal size split is going to be about 8" and the diameter of a beer can or slightly smaller.

You'll probably have to feed splits fairly often, maybe every 30 minutes or so

[Calenk]

So I found something interesting wondering if this is normal.

I use a digital probe and have it at on the grate near the exhaust. What's happening is when I open the cook chamber the temp goes up significantly. Does this mean I'm not getting good draft? Is there a point where the stack can be too long? Perhaps I'm wasting all my heat just heating the firebox and not enough of it is moving through the cook chamber.

[Jlems]

Small splits every 20 minutes would be totally reasonable.

[West River BBQ]

You mentioned having another cooker. What is it you're used to cooking on?

[Calenk]

Originally Posted by West River BBQ

You mentioned having another cooker. What is it you're used to cooking on?

It was a very small new braunfels offset.

[mowin]

Seems to me if your temps went up when you opened the pit, your draft might not be sufficient. Is the opening from.the FB to the CC the proper size?

[WilliamKY]

I'm just guessing that opening the cook chamber creates a vacuum that pulls extra heat from the firebox and that causes your temp to spike. If it drops back down shortly after closing the lid I doubt it's anything to worry about. Sounds like a pretty tight unit.

[Calenk]

Originally Posted by mowin

Seems to me if your temps went up when you opened the pit, your draft might not be sufficient. Is the opening from.the FB to the CC the proper size?

I believe so. I'm not sure to account for the downward facing baffle hood thingy on the opening though.

[Calenk]

Originally Posted by WilliamKY

I'm just guessing that opening the cook chamber creates a vacuum that pulls extra heat from the firebox and that causes your temp to spike. If it drops back down shortly after closing the lid I doubt it's anything to worry about. Sounds like a pretty tight unit.

Ok yeah that's kinda what I was thinking. It does drop pretty quickly after closing....it actually was kinda helpful in getting a new split to catch quick and avoid white smoke. I just added a split and opened the cook chamber and it fired right up.

[Zig]

The Feldon's BBQ Pit/Smoker Build Calculator says the stack only needs to be 30" high if you wanted to cut some off.