Gravity Fed Smoker Build - Stumps Clone

[goldman smokers]

I want to make a clarification that came up with a fellow member.

We were talking about the hole size into the cooking chamber and the heat deflectors.

I would say the hole to the cooking chamber is an important size to keep in mind. My hole is 6" tall by 8" wide and the area where the coals are lit is square. Meaning I have a 6h x 8w x 8L box which translates to 384 cubic inch of space in which the coals are lit. Anything above this area is not lit (why? I have no idea it just works out that way.) The bigger this space and hole size into the cooking chamber the hotter your smoker will get, however it should be proportional to the cooking chamber.

I used two types of heat deflectors on mine. one is a 6"x8" piece of 12ga metal right at the opening of the cooking chamber welded at a 45 degree angle. The second is a huge plate that is as wide and deep as the entire cooking chamber. And I set it at an angle, higher on the fire side and lower on the opposite side. I cut a notch 2" x 18" in it running almost the entire depth of that plate and is held by some angle iron (it is removable). This notch is opposite the fire, forcing smoke to accumulate in that lower section and find it's way through the notch, insuring that not fire every gets close to the lower rack. Some guys drill holes in it but I notched it to insure no flare ups. Now the fire rolls out into the cooking chamber which is why all this deflectors are needed. It will continually lick that 6x8" piece of metal. That large plate absolutely insures that no flames near that bottom rack and only smoke does. I realize now in looking at my old drawings I should have put that on there but a lot of it was small field adjustments.

Does that all make sense? If not I'll draw it out and post it should anyone need it.

 

[goldman smokers]

 

[goldman smokers]

Pardon my 3D drawing not to scale but maybe this will help someone. Just chatting with fellow member about possibly a round chute. Like a pipe. Not a bad idea if you aren’t doing a tapered chute it will save days of fabricating and welding

 

[goldman smokers]

Some more questions came up about insulation, hinges and fire box construction (specifically is it nesessary to extend it beyond the box)

1. I used mineral wool insulation my frame is 2” square tube so I ordered some from Lowe’s of the appropriate thickness. Depends on your climate I’d say. Even in Southern California where we have the best weather in the whole US it burns considerably more fuel in the winter than the summer. If you look at my pictures. Everything I painted in red gets warm but can be safely touched. Everything in silver will burn you if you touch it the silver is 1200 paint where as the red could only handle 500. But the red only gets slightly above 100 degrees to the touch and the silver gets way way up there. For this reason I think insulation would be nice because it would mean you wouldn’t have to worry about touching most of the smoker with your bare hands.

2. I bought a 6 foot hinge and cut it up on my saw and used it for all 3 doors. It’s a mild steel but has lots of strength. I made my doors and installed the gaskets I laid the smoker flat and placed the door on top. This allowed for the thickness of the gasket. I screwed it together with a bunch of screws.

3. It comes flush with the box. Then I extended it past, I don’t remember why I did that I added a 1” x 2” piece of squaretube. Probably wasn’t necessary. Actually in looking at it, it’s totally unnecessary. It just makes an area for ash to collect.

 

[Diggerg]

Could you show us your fan setup please.

 

[goldman smokers]

You want a picture of the internals? I don’t think I have it but I’ll send you the link to the fan I used and draw you a diagram tonight. Also I’ll send you the wire you should use to keep the wiring internal. You’ll need a 12 volt transformer too. I went through a lot of different variants on the wire before finding what I liked. I basically “grounded” like a car the negative lead from the transformer to the frame making so I needed half as much wire.

I just did 1 whole packer brisket (meat was shit unfortunately it had been frozen too long and turned out tough even at 208 internal temp). 2 pork butts and 3 baby back ribs and temp was incrediblely stable with the fan system.

 

[Diggerg]

I was just curious about your fan placement.

 

[goldman smokers]

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• goldman smokers
• Aug 12, 2015

Hopefully this helps

 

[goldman smokers]

This is the Fan i used


It feeds into a piece of 1x1.5 I think it is that had a right hand bend into the fire box just above the ash tray

 

[Diggerg]

Is it behind the small chequer plate at the bottom?

 

[Diggerg]

I'm planning on starting a build in Feb sand just pulling ideas together. I like the fact that the fan maybe hidden from sight

 

[goldman smokers]

I’ll put up a comprehensive post tonight about the fan system

 

[Hawging It]

Well... I have done it! I completed my first smoker. I was inspired by the Stumps Smoker; though I don't want to say clone. I have used this forum countless times and thank everyone for posting pictures because it inspired me and helped me build mine.

My gravity fed smoker has an internal fan and wiring for hassle free electronically controlled temperature regulation. In can run on 12v DC or 120v AC. The steel cost me $800. The entire temperature system cost $50. I painted it with Rustoleum paint, the red paint is their 500 degree Ford Red Engine Paint, the silver is their 1200 degree Metallic Silver Ultra High Heat paint. I did this because I was concerned about that side panel getting too hot from the firebox. Results look great! I purchased the paint on Home Depot's website $100. It took 7 cans of red and 2 silver. The door handle is from a Viking Dishwasher that I bought on eBay for $40. The 1.5" ball valve is from Smokey Maple and is 304 Stainless Steel purchased on eBay for $35 (super cheap!). Red Casters were purchased from Home Depot in store (and they are super smooth). The final build cost was about $1300 and it took me about 5 months every other weekend to complete.

Of course I had to polish it off with my own logo cause it just turned out so great and works so great! The fan kicks on every half hour, boosts the fire and then shuts off. I have been cooking my pork butt at 270 for 8 - 10 hours and it's marvelous. Same temp for ribs but only 2.5- 3 hours in there. I put a pan of water on the bottom shelf, leaving me 3 shelves to cook on.

If anyone needs advise, help or links I am happy to help so don't hesitate to message me.

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• goldman smokers
• Aug 12, 2015

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• goldman smokers
• Aug 12, 2015

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• goldman smokers
• Aug 12, 2015

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• goldman smokers
• Aug 12, 2015

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• goldman smokers
• Aug 12, 2015

Looks like a top quality rig. Great job.

 

[swirvin2000]

View attachment 362805

Great Picture, just wondering if the other three sides of the bottom of the shut are solid? it appears in this that the charcoal has about 6 In. of "burn area" for lack of better term, with and additional 8 inches below the grate for air flow and ash.
Has this been enough area to get enough heat? or would you recommend a bit more or less burn area?

 

[swirvin2000]

Great Picture, just wondering if the other three sides of the bottom of the shut are solid? it appears in this that the charcoal has about 6 In. of "burn area" for lack of better term, with and additional 8 inches below the grate for air flow and ash.
Has this been enough area to get enough heat? or would you recommend a bit more or less burn area?

shoot.... not shut.....

 

[goldman smokers]

It’s been forever since posting thought I’d share my best brisket ever. Ridiculously good! Cooked at 275° till internal temp was 165°. Wrapped in 3 layers of red butch paper and taped with white masking tape and cooked till 210° internal temp. I used Obe ques Beef Brisket Rub. This brisket was so good it didn’t require injection. Knocked this one out of the park. Smoker works incredibly 5 year later. It’s so reliable I never have to worry about temp fluctuations. I always used a full sheet pan full of water at the bottom shelf to add humidity and helps keep that temperature super consistent.

 

[goldman smokers]

Still turning out amazing meat 6 years later. Though my true love is pulled pork, brisket just photographs so well and man does it taste amazing.

We recently had a house guest that doesn’t eat red meat so I did smoked salmon and it was a game changer. I don’t like fish but this was amazing.

 

[goldman smokers]

Quick update — I’ve been watching Chudds BBQ and Mad Scientist BBQ on YouTube and wow did I up my game. Fully rendered fat on my briskets, dark black bark. My ribs are better, it’s sensational BBQ. What’s amazing is I didn’t realize my smoker’s full potential till 7.5 years after I built it. It’s as good as an offset YES I SAID IT!

It’s a journey. I look back at the photos from 3 years ago of my brisket and I cringe but it’s part of the evolution.

On the technical side I dumped the 12v transformer for a Milwaukee M12 battery. I bought the socket on Amazon. A 4.0 runs the smoker indefinitely. A 16 hr cook and the battery was half full. But I have options. Alligator clips for 12v lead acid battery, 12v external transformer or M12 battery . If it wasn’t like 500lbs I’d take it to friends houses, very versatile.

 

[goldman smokers]

Just to add in case it helps anyone.

I trimmed the brisket just as on Chud’s BBQ YouTube



Rub:
2 parts 16 mesh black pepper
1 part diamond crystal kosher salt
1 part Lawry’s

Apply rub so brisket is speckled with black pepper.

Cook uncovered at 250° till 180° internal but really it’s when the fat is rendered and as explained by Mad Scientist BBQ your finger pokes through the fat and the fat is yellow.

Wrapped in butcher paper with smoked Wagyu tallow (my wife prefers butter so I have since switched to butter but I prefer the tallow)

Cook at 275° till 205° internal or probes tender

Rest Brisket over night at 160° in oven - but this one I rested 20 hours because we had it for dinner the next night and I will say it was a bit long. Since cooking this I’d say try not to exceed a 16 hr rest otherwise you run the risk of over cooking it. This brisket was sensational even with a 20 hour rest.

The total cook times was about 14 hours but here is my take away. I got a 21lb brisket. It was a monster. It’s shear size meant it would take a while and I really think that contributed to that beautiful bark.

For wood chunks I used California Oak cause thats what we have here and it’s free when I trim my trees I get plenty of it.

Lastly cool tip. I made burgers with the trimming in a Kitchen-Aid meat grinder. I ran it though twice on the smaller die. 80/20 eye balled meat to fat ratio definitively didn’t weight it out I’m guessed at it

just for fun here are some ribs I cooked a few weeks back

I have also been making my own BBQ sauce and it’s surprisingly easy and fun to make and tweak to your taste

 

[KimberlyO]

BEAUTIFUL job!