New Build

[uga fan]

I've keep reading all these posts and it has me going nuts to start a build. I checked with a local scrap metal dealer and get recycled air compressor tanks for around $60. They are aboht 48" tall with a diameter around 24". I have purchased a new plasma cutter/tig/stick welder and a new mig welder mainly for smoker builds. Before I buy any used compressor tanks I would like some feedback from anyone that has used them. What to look for, what to avoid, are they functional etc.. Also, will the finish need to be removed? Curious if the paint can withstand lower CC temps, I know they wont handle fire box temps. Any help and suggestions will be greatly appreciated!!

 

[daveomak]

UGA, evening..... compressor tanks..... some high end tanks may have an "anti rust" coating inside... If it was a compressor that had oil in the crankcase or an oiler on the air supply for air tools, it will have an oil film,,, could cause a fire when cutting into it.... Fill with soap and water before cutting into it.......Safety first.... Depending on the interior coating, you may want to have the inside sand blasted.... I have no idea what coating they may use.... The only thing I know is.... pressure vessel explosions can bring lots of money if you are on the wrong end.... If you are the manufacturer, it costs.... sooooooo, I'm going to assume manufacturers do all they can to keep the integrity of the tank by using some sort of coating.....
Check the label for tank thickness... 1/4" at least would be good... Short and fat tanks, lend to more sq. in. cooking surface and less surface area for heat loss when building a reverse flow smoker.... long and skinny tanks will provide different temp cooking zones... not much different but a bit... and that can be adjusted using heat deflector plates or insulation....
To sum all this up...... anything is fine... if the price is right.... and you can cook what you need to.... The knowledgeable membership here, can help you build the best smoker for miles...

 

[uga fan]

Thanks for your input Dave, I will definitely flush before cutting. As far as the sand blasting goes, those were the types of questions I was hoping to get answered. If I have to spend $200 on sandblasting, I can buy a sheet of 1/4" and have it rolled giving me the same size CC for close to my the same price without the risk of an explosion!! Seems like, if the compressor tank will work with little or no sand blasting, it would be a very economical way to make smokers. The biggest cost will be the firebox. Im itching to get started, but dont wanna run the risk of leaping blind. Hopefully someone with experience on these tanks will chime in shortly!

 

[daveomak]

Many folks use a "burn out" method to remove any residue inside the smoker.... Elevate the temp in the smoker to 500 ish degrees to burn it out.... That will off gas or burn anything that will or might contaminate food products at a smoking temp of 250-300 and make it safe... as long as any residue is removed with a wire wheel or some other mechanical means...
I'm describing the "extreme" conditions here to help you make a "safe to use" smoker.... Then the smoker is coated in veggie oil, or something similar, to have a baked on coating like a cast iron frying pan.. Realize your food won't come in contact with the tank like a frying pan....

Dave

 

[radioguy]

UGA,

The majority of compressor tanks tend to be made of thinner stock.  The tank in my build is 3/16" on the main wall, rolled and gas welded to 1/4" pressed ends, the tank is 80+ years old, but the price was right.  If you are really wanting 1/4" then maybe you should go and have something rolled or look at propane tanks in the size you want.  Mine was painted and I assumed it was lead based so rather than wire brushing I burned it a few times.  It had oil / rust on the inside.  I did spend a lot of time cleaning it inside and out.  Since it was old I spent more time patching pin holes where it was rusted through.    

It depends on what your budget is ...both $$ and time.   I am going to do a sandblast after all that grinding, given the time I have invested.  A good blast will ensure a great paint job.   

BTW, I see that you have already acquired some tools.  Please invest in some type of respirator.  Your lungs will thank you.  I picked up a 3M half face mask of of Amazon for about $30.  It works amazingly well. 

RG

mask.jpg

• radioguy
• Dec 30, 2013

 

[uga fan]

Dave and RG thanks for the input. I priced some 1/4" plate metal today, $353/sheet. So I would be looking at over $700 for the cook chamber and fire box.. While my personal smoker is 1/4", this is an economy build for a friend.. Basically a $300 difference since I can get the compressor tank for around $60. He wants a patio version like a few builds that are being done on this site now. Bottom line, he doesnt wanna spend the extra cash for a 1/16" of metal. But if there is gonna be several hundred dollars spent on prepping the tank, the common sense move is buying new thicker metal rather than spend essentially the same plus losing weeks of build time. If the exterior paint will be ok for the heat of the CC and a simple burn out and some wire cleaning will suffice, the compressor tank is how he wants to go. Based on the weight of the tank compared to the weight of a sheet of 1/4"(260 pounds compared to 340) I am assuming 3/16" diameter. How much of a disadvantage is this gonna be considering its for home use not professional competetion cooking?

 

[daveomak]

The thinner metal will use a few more sticks of wood or a few more pounds of charcoal .... per smoke...

 

[uga fan]

So a little efficiency loss but still functional.. Ok no big deal. I've seen smokers that are basically made out of sheet metal yet still functioned and turned out great meat. So unless I hear some type of objection soon, I think we're gonna proceed with the compressor tank.

 

[radioguy]

UGA,

Dave is correct about using more fuel.  Thicker metal will take longer to get up to temp, but is will retain that heat for a longer time (thermal mass).  Temp recovery time after re-stoke or door open peek/baste will be shorter for a thicker tank.   A thinner walled tank will vary much more in temp during windy/cold conditions. 

As far as weight I would not be too concerned.  Mine weighs in at about 350lbs now and will probably be 450 when finished.  If you put some wheels on it and balance it, moving is not much of a concern.   The main thing about the weight is wrassling with it during the build. 

Choose your tank wisely as it is the main piece.  It I had to do it all over I would like a tank 22-28 inches wide (mine only 18").  This gives you space for a wide cook grate and 2nd grate above it.  It you have a good selection of used tanks take your time and find one that has thicker walls.  They are out there....somewhere. 

BTW I have no experience cooking on a RF.  All my knowledge has been garnered by reading here and asking questions.  Search is your friend.

This is a great forum, great people, good advice and many opinions!

RG

 

[pig sooie]

UGA I just finished, or about to finish, a air tank build and have been cooking on it for about a month or 2. The tank i had was a older craftsman 60 gal. and the thickness is a little thiner than 3/16. Orginally I was going to use it as just a patio model but ending up buying a small 4x4 trailer, $150 HF, to transport it. What Dave said is right on the money, the thinner metal does not retain heat as well but on some warmer days you can not tell. I just finished 2 dear hams this christmas and the outside temp was around 35 and their was not any problem as far as maintaining it. On a side note I did go with 1/4 for the fire box and baffle plate, it is a reverse flow, and their is a even heat across the chamber. Total build cost with the trailer was around $500 and I got the tank for $50. As far as sand blasting I did not, all I did was do a good burn out with redoak on the inside and then used a wire cup on my a grinder to clean the outside and inside. After the burnout the paint on the out side just fell off. Then I seasoned the inside with bacon grease for about 4 hours at 325 deg. Compresser tanks do make good smokers and their is a less of a chance of them blowing up, but still take the safety precautions when cutting it for the first time. I took the main drain plug out of the bottom which left me with about a 2 inch hole to fill up with water and dish washing liquid before I did my first cut. As far as your question on the paint I would remove it and go with a high temp paint, I'm cheap so I just used a couple of cans of rustoleum bbq high temp in a can. I have some pictures of my build under my thread, check it out, I will add some more this evening to let you see where I am at as of now. Also if you have a plasma you will be able to knock it out in no time, all I had was grinder with a metal cutting disk so it took a while. One suggestion is if you can get your metal for the firebox sheared do it, it saved me a lot of time.

 

[alaska]

UGA... Welcome to the forum. I started off with an 80gal compressor tank (check out my build) fortunately it did not have any coating inside and just a hint of rust. It is 3/16 thick and like the guys mentioned I will burn a little more wood. I'm up here in tropical Alaska so I insulated the FB and I like the look of the round tank. I believe having the FB insulated will help a great deal. My inside FB is 1/4 inch diamond plate and some my wonder why spend the money on diamond plate if it's going to be covered but it was a great deal of less than a 1/3 of the price. There was a guy advertising it on Craigslist who had over 100 sheets that he was going to build a boat out of and he changed his mind so I grabbed 14 sheets for fun. Im looking forward to your build...Jerome