Help on calculator

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gonzz
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Help on calculator

Post by gonzz » January 24th, 2017, 7:27 pm

I purchased a custom built smoker. Here is the dimensions.

cooking chamber - 48 in long x 20 in pipe
FB - 20 " x 20" pipe

Opening from FB to cooking chamber - 9.5" wide x 4.5" height

Chimney stack - 4" square 32" height.

I'm thinking my FB is to big. Thanks for any help.



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Big T
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Re: Help on calculator

Post by Big T » January 24th, 2017, 8:37 pm

It looks like it's 125% of the recommended size, 115% is pretty much the max on the FB.


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Re: Help on calculator

Post by gonzz » January 24th, 2017, 11:49 pm

Do i need to bring it down to 115%?



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Re: Help on calculator

Post by Big T » January 25th, 2017, 12:13 am

Are you having any issues and if so what type ?


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Re: Help on calculator

Post by Rodcrafter » January 25th, 2017, 7:10 am

That's a great question! If you want to try to reduce the size you can place bricks on the bottom of the FB. That might have a positive result. I was wondering if the throat is cut at the top of the FB and the bottom of the CC?


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Re: Help on calculator

Post by gonzz » January 25th, 2017, 11:10 am

The throat is cut at the top of the FB and the bottom of the CC. Not having issue but wanted to see how close I to 115%.



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Re: Help on calculator

Post by Rodcrafter » January 25th, 2017, 3:36 pm

Ok so as BigT pointed out the FB is at 125%

But the throat opening you have is only 42.75 it is supposed to be 50.27 square inches

If you laid some 2" bricks in the bottom of the FB it would put your FB down to about 115%. I have to admit I'm guessing on that number because the shape of the FB. If it were a rectangle it would be 101.25% so allowing for the dome at the top I would give it about half the reduction back.

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Re: Help on calculator

Post by gonzz » January 25th, 2017, 8:41 pm

What will I gain by going to 115%? Just curios how this works.



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Re: Help on calculator

Post by Rodcrafter » January 25th, 2017, 8:44 pm

It is the correct cubic feet of heat vs the cubic feet to be heated. It is all about "BTU"s and draft. Frank will be along soon to explain the process.

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Re: Help on calculator

Post by Squiggle » January 26th, 2017, 3:11 am

I think you just got BTU'd by RC there, only slightly though, lol. As he mentioned, OB1 will be able to give you a good BTUing soon. =))


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Re: Help on calculator

Post by Rodcrafter » January 27th, 2017, 6:05 pm

That's right Squiggle.


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Re: Help on calculator

Post by gonzz » February 5th, 2017, 1:46 pm

Ok I'm going to try and open the throat to 50.27 sq inches and put 2" bricks on the bottom. What kind of bricks do I use? Also When my smoker gets high in temp it's hard to get the temps down. Will this help after this work?



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Re: Help on calculator

Post by Big T » February 5th, 2017, 7:51 pm

You will have to use some type of fire brick or it won't last very long. What are you using for fuel, charcoal or wood? Which ever you use you'll need to use a small amount to maintain temp and add more fuel as needed. I start my cooker with a chimney full of charcoal and a couple of small splits of wood and then add a couple of splits every 45-60 minutes or so. You'll have to do a few test burns to see what works best for you but usually a small clean burning fire works best.


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Re: Help on calculator

Post by Rodcrafter » February 5th, 2017, 8:07 pm

I agree with BigT, the fire needs to be the right size for your smoker. I have heard Gizmo call it a happy place or a sweet spot. Well let's just say he was referring to the temperature and fire combination that your smoker works at the easiest.


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Re: Help on calculator

Post by gonzz » May 11th, 2017, 4:48 pm

Big T wrote:You will have to use some type of fire brick or it won't last very long. What are you using for fuel, charcoal or wood? Which ever you use you'll need to use a small amount to maintain temp and add more fuel as needed. I start my cooker with a chimney full of charcoal and a couple of small splits of wood and then add a couple of splits every 45-60 minutes or so. You'll have to do a few test burns to see what works best for you but usually a small clean burning fire works best.

I am using wood as a fuel source. I lite it with a flame thrower. I will get some fire bricks this weekend and give it a shot. Thanks for the info



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