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20" Pipe RF Smoker

geothermal

Smoke Blower
91
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Joined Jul 16, 2014
Oversize FB's seem to work very well..... 1/3 of the CC and larger.... More space under the wood grate for ash to collect.... More wood controlled at a lower temp for long duration cooks... More of a uniform heat for consistent temps... BUT, aesthetics is important also....

Personally, I would lean toward a perfect smoker, that cooks better than whatever is my second choice....

For the doors, do you have something similar planned for what is pictured below...... Dave

......click on pics to enlarge.....


 Couple of questions:

  In the drawing on the right, I'm not sure I understand what "Divide Areas 80-20 / 90-10" means.

According to Feldon's calculator if I size my firebox at 100% it calls for almost  4 openings 1.5" wide and 3" high.

Would that be 3 of them at the bottom and one of them at the top? Or should I change the calculator to the actual size of the FB and use those dimensions to size the intake openings? That comes out to almost 5 - 2"X3" openings. So would that be 3 on the bottom and two on the top?
 
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daveomak

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80/20 ... 90/10 is the approximate ratios for the air intakes..... bottom inlet 80/90 % of the calculated air inlets and 10/20% for the upper air inlets.... it's not that critical.... just ball park....

If the calculator calls for 4 openings 3 x 1.5 .... that is 18 sq. inches... I would go with 3 sq. inches on the upper and 15 sq. inches on the lower air inlet.... or something close..... 1 each 2x2 on the upper and 4 each 2 x 2 on the lower..... that 20 sq. inches... close enough for pulled pork....
 

geothermal

Smoke Blower
91
14
Joined Jul 16, 2014
Made some progress on the FB Door over that past few days.

Cut this 1 1/4" X 3/16 angle with my Milwaukee Metal circular saw every inch. Then bent it around the door plate while it was all secured to the FB.



Put wood shims all around the inside of the angle and tack welded each seam.


Angle frame welded and ground. Door panel drilled for blind welding.


Use 1" X 1/4" angle inside the perimeter of the FB. Same  cuts every inch.


FB door blind welded and set on FB


Inside angle welded and ground.


Cut out intake vents and vent covers with plasma cutter. Closed position.


Open position. I put 2 on the top just for fun and my FB door needed a face. Next I'll weld on some tabs to hold the plates in place.

 
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lendecatural

Smoking Fanatic
688
49
Joined May 4, 2013
The angle bends turned out really nice! I wish I was that good with stick welding, it's been too many years since I've done much of it. I'm really good at getting sticks stuck...
  Love the "Happy Face" vents on the door, very nice touch.
 

geothermal

Smoke Blower
91
14
Joined Jul 16, 2014
 
The angle bends turned out really nice! I wish I was that good with stick welding, it's been too many years since I've done much of it. I'm really good at getting sticks stuck...
  Love the "Happy Face" vents on the door, very nice touch.
As a lot of us did, I learned to stick weld in High School, long before mig came about. It's been a few years (like 43 years), but I'm getting better. Lots of practice on this project. Sold my mig welder last year when I moved. Wish I had kept it, but will get another one some day when I have a shop to work in. I had a 30' X 40' shop when I moved. Now I'm doing this in the driveway.
 

geothermal

Smoke Blower
91
14
Joined Jul 16, 2014
Got the FB almost finished. Not sure how the latches will be under heat.


After the first failed hing, these were a re-fab that work.


Got the smoking rack done.


Inside of FB Door.


Next will be the 4" smoke stack. I want to find a 4" coupling to weld to the plenum so I can remove the 4" stack in case I have to transport the smoker in my trailor.
 
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lendecatural

Smoking Fanatic
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Joined May 4, 2013
Is the 4" going to be pipe or tubing? If you use pipe, you can get a socket weld coupling and only weld one side.
 

geothermal

Smoke Blower
91
14
Joined Jul 16, 2014
 
Is the 4" going to be pipe or tubing? If you use pipe, you can get a socket weld coupling and only weld one side.
Yes, it's going to be 4" pipe. Thanks for the tip. Never heard of that before. I'll have to try and find one. Wow! Just found one at Granger for $93. Ouch!
 
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lendecatural

Smoking Fanatic
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Joined May 4, 2013
Yes, Grainger is usually high, check a pipe supply house. Other option is to cut the pipe and tack a short piece of 4" tube inside. Should be a fairly loose fit since schedule 10 4" really has an ID of 4.250" and you should be able to get the tubing at an automotive exhaust system shop. I made a pipe to tube adapter by cutting a very short piece of schedule 10, split it, cut a little off of the end, and made a sleeve to take up the .250 so it fit the pipe ID good enough to TIG weld. I was going to hose but in your case it could work with a little grinding to get a better fit.
 
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geothermal

Smoke Blower
91
14
Joined Jul 16, 2014
Yes, Grainger is usually high, check a pipe supply house. Other option is to cut the pipe and tack a short piece of 4" tube inside. Should be a fairly loose fit since schedule 10 4" really has an ID of 4.250" and you should be able to get the tubing at an automotive exhaust system shop. I made a pipe to tube adapter by cutting a very short piece of schedule 10, split it, cut a little off of the end, and made a sleeve to take up the .250 so it fit the pipe ID good enough to TIG weld. I was going to hose but in your case it could work with a little grinding to get a better fit.
Thanks again Len. I'll be off to the steel yard to see what I can find. Made some progress today on the back wheels. My vision is starting to take shape.




 

swechef

Fire Starter
57
12
Joined Jun 19, 2012
This build just went from really cool to totally awesome! Can't wait to see what's next!
 

geothermal

Smoke Blower
91
14
Joined Jul 16, 2014
Got to the steel yard Monday and picked up some 4" x 1/4" pipe for the smoke stack and front wheel attachment. The 4" id pipe is 4 1/2" od. They had some 4 5/8 id x 3/16 pipe that I bought to use in place of the Socket Weld Coupling like Len suggested. A little pricy at $26/ft but I only needed a foot.  It will be a little loose at the smoke stack, but I think I can put some fire box gasket rope down inside at the bottom of the 4 5/8 coupling to at least seal it off good and then some high temp silicone around the top. Then I'll be able to remove the stack when I have to transport the smoker in my enclosed trailer. Stay tuned for more pictures.
 
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wolfman1955

Master of the Pit
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47
Joined Nov 17, 2013
This is the best build thread I've seen on here in a long time!!! Love the tractor theme!! What brand you going to go with on the paint scheme, Deare, Farmall, Massey?
Just a thought, you may want to incorparate some sort of leveling system in your front wheel mounting brackets, something like a jack stand.
 
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lendecatural

Smoking Fanatic
688
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Joined May 4, 2013
0.062 all around isn't much of a gap, get it all welded up and you may find it's a good slip fit. It doesn't have to be a tight fit like the firebox intake, that hot air wants the hell out of the CC.
 

geothermal

Smoke Blower
91
14
Joined Jul 16, 2014
This is the best build thread I've seen on here in a long time!!! Love the tractor theme!! What brand you going to go with on the paint scheme, Deare, Farmall, Massey?
Just a thought, you may want to incorparate some sort of leveling system in your front wheel mounting brackets, something like a jack stand.
Thanks Wolfman,

  I think I'm going for the rusty old "Steam Punk" look. Not sure if I'm even going to paint it yet. Yes, the front end is going to be a challenge. I was hoping to work on that today, but the weather isn't cooperating. Good idea on the jack stands. I'll have to see how stable it is with what I have in mind.
 

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