Custom Smoker Problem
 

Hello everyone, this is my first thread so bare with me! I am new to smoking but a veteran in DIY so naturally I have never bought a meat smoker, but I have built two! My first one was just a webber grill that I welded on top of a steel 5 gallon bucket where I made my fire and it worked ok but it was tiny. My second smoker, which I am writing about now (shown below) I may have went over board with in size!

What I built:
I built an offset vertical barrel smoker out of a 30 gallon drum (fire box) and a 55 gallon drum (meat chamber). I took a metal storage rack I had laying around and customized it to fit the barrels, welded all the joints together, and then welded the barrels in place. I connect the barrels with a 4" iron pipe welded between them (from the top of the fire barrel to the bottom of the meat barrel). For air inlet on the fire barrel, I JB welded two 3/4" black iron pipes with ball valves. I also made a standard charcoal basket out of 3/4" expanded steel which sits in the fire barrel on top of two bricks (see pics below).

My Problem:
My first run was a few weeks ago using lump coal with the minion method and it ended up working out great, but I had a few issues during the cook.
First of all, the meat chamber barrel (55 gallon) took what seemed like for ever to heat up (I think over an hour and a half) and I couldn't get it much hotter than 150 degrees. I instantly thought "This barrel is way to big". I decided to cook that meat I had planned anyway and just figured it would take way longer.

What really confused me was the meat, which was 4 tri-tips and two whole chickens, only took 4 hours to cook and they all came out amazing!
So then I started thinking maybe the 6$ temp gauge I bought at Home Depot was the problem and I was really cooking at higher temps the whole time??

Solutions?
A few ideas I had, which I'd love everyone's opinion on, are:
1. Starting a small charcoal fire in a metal bowl in the meat barrel to help heat it up quicker.
2. Buy a better temp gauge (which I'm going to do anyway).
3. I already added two more air inlet pipes with ball valves (not shown in pics) for a total of 4.
4. If I still can't get the temps up in the meat barrel, maybe run another 3" or 4" pipe out of the side of the fire barrel and into the bottom of the meat barrel to transfer more heat.

Other than the heat issue, the smoker worked great. There were almost no smoke leaks except for a few trickles coming out of the lid on the fire barrel (its has an old rubber gasket which I need to replace). The fire barrel and the 4" pipe were extremely hot during the cook, I mean you couldn't even touch them. The meat barrel was also hot, but not nearly as hot. You could hold your hand on there for a few seconds.

The Smoker with 1/4" Aluminum diamond plate door
http://www.bbq-brethren.com/forum/at...1&d=1364494396

Here it is with door open. You can see the 4" iron pipe sticking through the bottom of the meat barrel, my high temp silicone cloth gasket, and the three 22" round Weber grills.
http://www.bbq-brethren.com/forum/at...1&d=1364494396

Here is the fire barrel with the two (now four) 3/4" pipe inlets.
http://www.bbq-brethren.com/forum/at...1&d=1364494396

Inside the fire barrel. Those are the two bricks that the charcoal basket sits on. The bottom inlet has a 6" pipe nipple the extends in and sits directly underneath the charcoal basket. The other three (only one shown) have a 2" nipple that feed the basket from the side.
http://www.bbq-brethren.com/forum/at...1&d=1364494396

Chicken and Tri-tip from my first cook!
http://www.bbq-brethren.com/forum/at...1&d=1364494396
http://www.bbq-brethren.com/forum/at...1&d=1364494396

Well, please let me know your expert opinions on my build and maybe some ideas on the temp problem. Thanks guys! P.S. I love this site!!

I would start with a new gauge. Buy a tel-tru they are awesome! You might just want to get a Maverick ET-732. Gives you pit and meat probes.

Once you have a good gauge then start troubleshooting. I would not do anything until you find the internal temp of the meat chamber.

The meat looks great!

+1 on tru tel gauges, also maybe move the 4" pipe higher in the firebox chamber barrel, your trapping alot of heat in the top 3" of the barrel, and as u suggested more air to fire, but dont do any changes till you get good gauges theres is a brethren here who sells them good prices and grest people, 5-0 bbq out of maryland, bbqequipmentstore.com ive used them multiple times. 1 more thing, how do you control your exhuast draft? is there something in the lid of the cook chamber?

I can't tell from the pics. What is the "Meat Chamber" exhaust diameter?

There is a 2" threaded hole in the top of the meat chamber. The barrel already had it there with a cap that screws on. I leave the cap off while I cook of course, but do I need more exhaust? Maybe more exhaust will suck more heat from the fire chamber?

Sounds like you have a bad gauge if you can put your hand on the chamber for only a few seconds! I think it's plenty hot! Awesome idea and great pron!

New gauge for sure, get an accurate temperature.

Put a chimney on the meat barrel, it will draft better, and heat faster. I would want a 3" chimney myself. The 2" hole is convenient, but, with that setup, a 3" chimney will draft better.

That's what I was hoping too! Plus that much meat at only 150 degrees (supposedly) should have took longer than 4 hours I would think??

Just from the looks of the meat I would say you are hotter than 150.

I would take your thermometer off and test in a pan of boiling water, should be close to 212f depending on your elevation, then also try in a glass of ice water, should get close to 32f (if it goes that low)

At least you will know whats up with the thermo

The location of the thermo might not be any good either

If the thermo checks out, I would just set it on your cooking grate and fire it up, see what it reads then

i would take the 4" pipe from the firebox to the smoke chamber and have it come out of the top of the firebox and then go into the smoke chamber, hot air rises and is collecting at the top

Good call! Will try tonight. Also I think youre right about the location, I just thought about it and the temp gauge only has about a 2" probe on it and my door is curved with a radius. So basically the probe isn't really even getting into the chamber much at all. Bad design.

You need to get that buldawg dude in here and look at it.

The build looks great to me but I would think about how far your heat has to travel before it gets to the meat. In a UDS the basket sits right below the meat and in your set up it has to go up a 55 gallon drum then over into the cooking chamber. It seems to me your fire has to work twice as hard. IMHO you have to look at it like a traditional offset smoker.

if this ends up being the case then you could build a platform or raise the fire grate somehow to get it closer to the outlet.

But from the looks of your meat I dont really think you have an issue

Nice looking build, it's kind of an offset-UDS. First step is definetly a couple new thermometers to find out whats going on in the cook chamber.

I'm thinking you might also have an air flow problem thats limiting your fire. Four 3/4 inch inlets only gives you about 4.7 square inches inlet and the 2 inch outlet only gives you about 3.1 square inches out. My gut says thats too small for an offset but there are lots of UDS builds with about the same; difference is the fire is in the UDS, not offset. I've never used one but maybe one of those BBQ Guru things with a blower would let you improve air flow without cutting more or larger inlets and exhaust. Let us know how it turns out.

PS: did you say you keep the exhaust closed when cooking? I would think you need at least the 2" open to get proper draft & larger might work better.

Thanks Andrew. Yeah I put the 4" pipe as high up as I could, it's just under that top corrugated bead/bump in the fire chamber barrel. I didn't want to mess with cutting a hole through that bead. There's only about 3" from the pipe to the lid of the fire barrel, so some heat is sitting up there. Maybe if I beef upy exhaust like landarc mention it will pull more of that heat through.