How To Build a 55 Gallon UDS Drum Smoker

Barrel smoker, charcoal basket, drum smoker, green chili, How to build a uds smoker, pork, pulled pork, Ribs, smoked meat, SmokerBuilder, smokerbuilder mfg, Uds, UDS Parts, UDS Smoker, Ugly drum smoker -

How To Build a 55 Gallon UDS Drum Smoker

Want to know how to build a UDS Drum Smoker?

You have no doubt been searching for answers to your questions about the proper way to build a UDS Smoker and have seen a lot of different approaches. Some look amazing and some look awful. Some seem easy to understand but difficult to do.

What if I told you there is a way to build your UDS Drum smoker without the need for expensive tools, welding, and difficult fabrication?

Well here ya go! No welding, no crazy tools required, no difficult fabrication and you can do it in less than a day!


How does a UDS Smoker work?

We will start by talking about some 8th grade science. The fire triangle.
fire triangle info graphic
Combustion requires 3 things.
  1. Fuel
  2. Oxygen
  3. Heat
For the fuel source we will be using charcoal.
The Oxygen or combustion air will come in through the air inlet dampers that enter in through the bottom of the smoker.
The Heat will happen when you light the charcoal on fire using a lighter or other flame.
In order to control the temperature in the smoker you change either the amount of oxygen or fuel depending on your type of smoker.
For a UDS Smoker we have a large fuel source, the basket full of charcoal, so we restrict how much air we allow into the smoker.
We don't want to have all of the charcoal on fire at the same time at the beginning of the cook. We actually want the charcoal to gradually catch on fire throughout the duration of the cook.
The method you use to light your drum smoker has a lot to do with the success of your cook and how well your UDS Smoker works.
I prefer to use a charcoal chimney and fill it with charcoal. I use a turkey fryer burner to catch the charcoal on fire.
The way I light a UDS Drum Smoker is to partially fill the charcoal basket with charcoal and then dump the lit charcoal directly on top of the unlit charcoal in the basket. (see my last blog post to learn how)
In the charcoal basket of the UDS there is approx 15 pounds of charcoal.
If all of this charcoal is allowed to catch on fire we would have a massive fire!
In order to be able to control the temperature we need to throttle how much air is allowed to make it's way to the charcoal basket.
The way we do this is by using air inlet dampers like the ones you see in the picture below.

There are tear drop shaped blades that attach to the top of the air inlet that open and close to allow more or less air into the smoker in an effort to control the temperature of the smoker.
To make a fire hotter we add more oxygen to it so we would open the air inlet dampers to increase our temperature or close them to decrease our temperature.
Once the combustion air is inside the smoker the fire will consume as much of it as can travel to the charcoal or "Coal Bed". Not 100% of the combustion air will actually make it to the coal bed.
Depending on how you build your UDS Smoker some air can bypass the coal bed entirely.
This can lead to colder or hotter temperature zones in on your cooking grate which can lead to an undesirable cook.
In order to prevent this from happening we have designed our DraftMaster™ system. 
SuperTuner Baffle Combo
This system utilizes a heat shield, block off plate, and a baffle plate to control combustion air flow before and after the coal bed to give you even temperature zones and more efficiency in your smoker.
You can build a UDS Smoker without these things but they will give you the best experience and results.
ANow moving upwards in the smoker, above the charcoal basket we have a round cooking grate where we cook the meat. Then we have the lid of the barrel and the smoke stack.
It is very important to make sure the lid seals tight! If the lid is allowed to leak air it will be difficult to control temperature. Remember, controlling how much air is allowed to get to the coal bed is how we control temperature.
All of these components play an important role in how well your UDS Smoker can operate. Now we will talk about the construction of your UDS smoker.

What are the parts of a UDS Smoker?

The Barrel

The first thing you will need to find is a barrel. You can use any size barrel but the most common is a 55 gallon barrel.
I prefer to use new barrels but have used all kinds of used barrels in the past.
Let's 55 gallon smooth sided barelface it, we call them "Ugly Drums" right?

Now your UDS doesn't need to be ugly though. The more work you put into finding a barrel the better.

You can use any barrel that hasn't had things like glue, caulk, tar, or other hard to remove substances.
The best used barrels are ones that were used for palm or coconut oil. These usually do not have what is called a "liner" in them.
Once you find a barrel with a liner in it you will understand what it is the moment you try to remove it. Oh and good luck, you're going to need it!
The liner is used for making a barrel "food grade" and it can be removed as well as whatever nasty thing was in the barrel in it's past life.
We burn the barrel out to make this possible. To burn your barrel out you simply drill all your holes in the barrel for your air inlets, etc. Then I build a fire in it. Then I use a shopvac in the blower mode like in the video below.

If you watched the video you will see the paint on the outside started smoking then the paint began to flake and peel. This is the best way to burn a barrel out that I have found.
If you try to use a propane weed burner on the outside of some barrels it will actually bake the liner on and make it harder to remove.
Once you burn out the barrel I recommend a process to clean the barrel that we learned by accident. We use a Nylon bristle brush and Green Powdered Comet. Yep, you heard me... Comet.
I don't know what it is about the Comet, but it is the only thing we have found that can get the liner out after burning the barrel.

Air Inlets

Keep in mind all we need to do is regulate how much air comes into the barrel for combustion air. In an attempt to make it simple to understand, all we need is a hole and something to cover it up with.
We can use most anything. Fabricated parts, plumbing supplies, or anything that can stick to metal and cover a hole.
The hole for your air inlet needs to be in the bottom of your drum.

I prefer them to Air Inlet Hole For UDS Smokerbe approx 3 inches up from the bottom and on the side of the barrel.

You can simply cover the hole with a magnet if ya want but having a easy to control damper that is easy to reach and won't get lost is best.
We have used all sorts of things over the years when making our drums but my favorite to date is our upright air inlets. These give you a really nice look as well as make it easy to adjust your temperature. It uses a 1.5 inch hole in the side of your barrel and has an easy to mount flange that is curved to match the side of your barrel.

One of the other options we have is our side mounted UDS air inlets. These are inexpensive and usually one air inlet will run your UDS Smoker at 250°F to 300°F no problem.
side mounted uds air inlet

These air inlets are nice because you simply drill an 1-1/2 inch hole and bolt it to your drum. No welding required! The flange is even pre-curved to match the side of your barrel.
There are other methods using 3/4 inch iron pipe or 1 inch iron pipe. If you do this you will need to weld a small pipe nipple to the barrel to get the best seal. you can try to do it with conduit lock rings or other fasteners also but these tend to leak and can cause your UDS Smoker to run hotter than you want.
Whatever you use, make sure it is tightly sealed so it doesn't let combustion air leak into your barrel. Having a tight seal will help you easily maintain your cooking temperature.

Charcoal Baskets

The main goal of the charcoal basket is to hold enough charcoal that you can cook for 12 hours or more. I have personally had my UDS run as long as 38 hours on a single load of charcoal.
While you might never have a reason to cook this long it is a great way to test and know your smoker is sealed well. 
I have made all sorts of charcoal baskets over the years. Some performed well and others not so good. 
The best charcoal basket I have made to date is the DraftMaster™ Charcoal basket. This charcoal basket is heavy enough to last for years and years but is still affordable on a budget.
charcoal basket for UDS smokerYour charcoal basket should hold charcoal in a tight enough pile that it can burn efficiently. If it is a large diameter and short then you would have a hot spot on one side of the coal bed. 

Keeping your charcoal piled in a  12 inch or so radius and at least 9 inches tall helps to burn the charcoal more evenly from top to bottom. 

You can purchase one of these or make your own. If you decide to make your own then you will likely use 3/4 #9 expanded steel which comes in sheets. Be careful when handling this material. It can be razor sharp!
Expanded metal is widely used in BBQ related applications. everything from charcoal baskets to cooking racks. 
If you decide to build your charcoal basket yourself then be sure you have at least 3 inches of space between the bottom of your barrel to the bottom of your coal bed. 
You can also include an ash pan in your design to make it easy to clean out the ash. An ash pan is not completely necessary but does make things easier to clean.
A handle is also a nice addition to your charcoal basket. You can use steel round bar or flat steel strap. A handle will make lifting your charcoal basket in and out of our drum easier and safer.

Baffle Plates and Heat Shields

While you can build a basic UDS without these items you will have a better first experience with them the major things they help you with are:
  • preventing temperature spikes when opening the lid
  • protecting your paint job on the outside of your barrel
  • improving efficiency
  • reduce hot spots and cold spots
  • prevent down drafts inside the barrel
We manufacture a system that you can use in any UDS Smoker. Simply bolts together. We have several different options for each of these parts. You can mix and match them in any combination. 
UDS heat shield and baffle diffuserYou can build a UDS on the cheap without these things but I strongly recommend a baffle plate. This will help prevent some of the spikes in temperature you experience when opening and closing the lid. 

The baffle plate should be placed at least 3 inches above the top of the charcoal basket. This gives the heated air mass a chance to mix before it goes up into the cooking section of your UDS Smoker.

A heat shield is used to prevent the direct heat from the charcoal basket from burning or damaging the paint or other coatings you have on your smoker. 
Our heat shield also has another purpose. It is used to set the baffle plate on and keep it the correct distance above the charcoal basket but also as a way to evenly distribute the combustion air coming into the smoker so that it enters the coal bed evenly.
This is also not entirely necessary to build your first UDS but it sure makes a huge difference in the way your new smoker will cook.

 Cooking Racks

There are many different styles of cooking racks available today. We manufacture several different ones. Ours are made of 12 gauge steel and laser cut so they are not sharp. 
cooking grate for UDS smokerYou can use the ones from big box stores also. they are not as durable but work fine for your first smoker. We also carry a ceramic coated one if you are on a budget.

Some people prefer to use 2 cooking racks, but I do not recommend trying to put more that one cooking rack in your UDS Smoker.

They are a pain to get in and out and the bottom rack will not cook the same as the top rack.
The cooking rack should be between 8 and 10 inches down from the top of the barrel. This gives you a good distance between the top of the charcoal and the food you are cooking.
I recommend using 4 bolts to hold your cooking rack in place. This will prevent the cooking rack from tipping when loaded unevenly with heavier meats.

Smoke Stacks

There are several ways to make your smoke stack. We make them out of 2 inch pipe. We make threaded, plain weld on, and flanged smoke stacks. 
The one you should use depends on your barrel lid. If you have a threaded bung in your drum then I would use the threaded connection. 
If not then I would use the flanged smoke stack. They are simple to install by drilling a 2 inch hole with a hole saw and bolt it to your lid.
smoke stack for UDS smokerAs for where to install your smoke stack, there are several considerations before you decide.

If you have the threaded bung then that is an easy decision. However, if you do not then we need to think of the other options you might want on your lid such as handles and hinges.

If you are planning on using a handle then decide if your handle will be in the center or the edge of your lid. If you are using a lid hinge then I recommend placing your stack in the middle. You will find  several options for handles and hinges in our site. I have even used the smoke stack as the handle in the past.

How to build a UDS Drum Smoker?

Tools Required

Let's talk about the tools you're going to need to build your new smoker. 
Here's a tools list:
  • cordless drill
  • 1/4 to 1-3/8 step drill bit
  • 1/4 inch drill bit
  • 2 inch holesaw
  • sharpie style marker
  • masking tape
  • 2- wrenches or ratchets size 7/16 
  • round and half round files
  • optional grinder with a 60 grit flap disk
  • tee square
  • tape measure
  • flexible measuring tape like a sewing tape
Depending on the options you choose and how you build your smoker some of these tools will not be required.
I use the tee square to establish a top to bottom center line on the front center of the barrel. You don't need to mark your barrel top to bottom just a couple refrence marks will work.
A tee square has measurements on it that can help you find the height of your grate or inlets quickly.
I use 1/4-20 stainless steel bolts and nuts for all the hardware. I use 1 inch long or 3/4 inch long bolts. It is not recommended to use zinc or coated hardware for sanitary reasons. You will use the 7/16 wrenches or ratchets to tighten these nuts and bolts.
Hole saws for drilling hole for UDS SmokerIf you choose to use our UDS Parts for your build then you will use an 1-3/8 sized hole for the air inlets and a 2 inch holesaw for the smoke stack.
If you use our thermometer the hole you drill for it will be 7/8 or a standard 1/2 inch conduit knockout size hole.
The files will come in handy for deburring these holes. I prefer the half round file for this. The round file will work well on the 1/4 inch holes.
You can use an optional grinder with a flap disc to debur the holes if you like as well. You might also find a grinder handy to grind off the excess bolt stems that are not being used after installing your parts. 
I like to use a flexible tape measure to measure around the circumference of the barrel for locating rack mounts, air inlet holes, and handles.

Laying out the holes to be drilled

We have a FREE set of plans to help you with the layout of your UDS Drum Smoker. You can grab your copy by CLICKING HERE... Grab Your FREE UDS Smoker Plans.
SmokerBuilder MFG FREE UDS Drum Smoker Plans
 The FREE plans show you all the dimensions and locations to mount your parts for your UDS Smoker. We also make a handy template for you to use to easily layout all the holes to be drilled in your barrel. You can get one of these templates by CLICKING HERE
SmokerBuilder MFG UDS Drum Smoker Layout Template
If you decide to build your UDS Smoker without the plans or the layout template follow these dimensions to mark the holes.
  • Air Inlets - from center line make a mark 10 inches to left and right. This is the center of each hole. Then mark 3 inches up from bottom of barrel on those locations. Drill these holes with the 1/4 inch bit first then use your step drill bit to make the hole the correct size. Use the flange of the air inlet damper to align your air inlet and mark the bolt holes.
  • Rack Mounts - along the center line make a mark down from top of barrel 8 inches. Then measure around your barrel the total circumference and divide that measurement by 4. This is the spacing for your rack mounting bolts. Mark these at 8 inches down from the top of your barrel. Use the 1/4 inch bit for these holes.
  • Thermometer - along the center line of your barrel make a mark 9 inches down from the top of your barrel. Drill this hole with your 1/4 inch bit first then use the step drill bit to make the hole 7/8 of an inch.
  • Baffle Plate - if using a baffle plate then along the center line of your drum make a mark 15 inches up from the bottom and repeat the same bolt spacing as your rack mount bolts.
  • Handles and other hardware - use the part itself as a measuring device by marking the bolt holes and drilling them with the proper sized drill bit. If using our UDS Parts you will likely use your 1/4 inch drill bit.
  • Smoke Stack - if mounting your smoke stack in the center of your lid then use a tape measure to locate center and drill the hole with a 1/4 inch bit first, then use a 2 inch holesaw to drill the hole bigger. Use the flange of the air inlet damper to align your air inlet and mark the bolt holes. You can get a FREE flange template by CLICKING HERE
SmokerBuilder MFG Flange Layout template

How to paint a UDS Smoker

This can be as easy or as difficult as you want it to be. If you are like me, you hate to paint. I prefer to use clear coat of some kind on my UDS Smokers. I like the looks of the raw steel personally. 
If you want to have a body shop quality paint job your are in for a lot of work! Surface preperation is the most important part of that kind of paint job.
For a good quality surface prep no matter what kind of coating you're using start with sproper safety gear like gloves etc. and get a can of wax and oil remover.
The surface of the steel will have an oily coating that will need to be removed. Use a good quality lint free towel and wipe every surface.
After wiping the steel with the cleaner sand the steel parts and the barrel. This can be done easiest with a random orbit sander and some 220 grit sand paper. I sand the entire surface of the barrel and all parts.
This will give the paint "something to stick to".

After sanding wipe off again with SmokerBuilder MFG DraftMaster UDSwax and oil remover and let dry. Once the steel is dry, just to make sure the steel is clean, wipe all surfaces again and let dry.

When you're ready to paint you will need to follow the paint manufacturers instructions exactly. pay attention to things like mixing instructions, additives required, painting environment, application, coating times, curing times, cleanup, etc.
Types of paint I have used are HVLP (high velocity low pressure- spray gun- this usually comes in a quart can), rattle can (spray paint), and powdercoat. 
Of all of these I prefer to get them powdercoated because I don't hafta do all the prep work but it can be pricey. HVLP requires the most work of all and can also be pricey. 
The easiest by far is to use good old rattlecan paint. For this kind of paint I prefer the VHT or Duplicolor brands of paint. they both make high temp rated paint. 
They both also make a high temp rated clear coat. This is what I have used on the last few personal UDS Smokers I have built.


Now for the fun part! You've done all this work and now you get to see it come together! First things first, be careful and don't scratch your parts!
I like to have some moving blankets handy to work on as well as some nitrile gloves, lint free towels that are scratch resistant, and some masking tape.
I use the tape on the surface if any wrench or ratchet that could come into contact with the paint while tightening the nuts and bolts.
Have some clear or color matched high temp food grade silicone handy to seal the flanges of the parts when doing the assembly.
Bolt everything together and let the silicone cure. If you got sloppy with the silicone, let it set up before trying to remove it. It will pull off easier than it will wipe off. 


How to season a UDS Smoker

Here's a video about how to season your new smoker...


Building your own UDS Drum smoker can be done many different ways for a huge range of budgets. My personal favorite way to help someone get started is to tell them to build one with minimal parts first and learn to run it.

Get some experience using it then start adding options.

What are the Basic UDS Parts required to build a smoker?

The bare essentials you will need are:

  • a 55 gallon barrel with a removable lid
  • at least 1 air inlet that is an 1-1/2 or equivalent
  • 1- 2 inch smoke stack 
  • a cooking grate of some kind
  • a charcoal basket that is 12x12 and has a charcoal depth of 9 inches
  • a thermometer
  • and some stainless steel 1/4-20 by 1 inch long bolts with nuts.

To make your build easy as possible we have several kits you can use to get started with. All of our UDS Parts Kits include the needed nuts and bolts to build your UDS smoker.

I hope this post has been helpful and I would appreciate your comments and sharing this with your friends on social media!

If you have any questions please holler at us by using the messenger button below or call us at 573-612-1315

Have a great day and enjoy your new UDS Smoker!


1 comment

  • Benny

    Where did you get that lid handle from?

Leave a comment

Liquid error (sections/article-content.liquid line 158): Could not find asset snippets/spurit_po2_collection_template_snippet.liquid