Propane Tank Into Air Tank, the EASY Way

210,930

80

38

Introduction: Propane Tank Into Air Tank, the EASY Way

I really like turning propane tanks into air tank, they last a long time as an air tank and the standard grill size holds enough air to fill 2 flat tires to 35 PSI on my car. The only problem is that I REALLY dislike removing the valve from the tank, sometimes I would even ruin the valve and not have a tank that is usable at all. On one city clean up day, I managed to get about 4 of these tanks, one was half full or propane yet and was still on the grill, I couldn't remove the regulator from the tank so I just cut the hose and went home with my new stash.

Once I remove the regulator at home, I inspected it a bit more and came up with a new way to get an air tank.

I know there are plenty of Instructables on this topic, but I have never seen it done this way before. There where tons of results that came up on "" Propane air tank" so I may have missed one.

Best of all, you only need one (1) adapter for an unlimited number of tanks.

Step 1: Remove Tank Adapter

Just remove the brass piece that screws into the tank from the regulator, this is easily done by clamping the regulator into a vise and using as crescent wrench to remove it, it is just standard threads which play a BIG role here.

Once it is off, you will either have a tiny, small, medium, or large hole in the end. If you have a medium to large hold, skip the next step.

In my case I had a Tiny hole, not much air will pass through that.

Step 2: Drill Baby, Drill!

Now it is time to find a drill bit and a drill, you want to have a drill bit sized anywhere between 1/8" and 1/4" 1/4" is the MAX size you can go. and it is the size that I went with.

That tiny hole serves very well as a pilot hole for the drill bit too, so no worries about going off center, Now put the brass tube with the thread collar removed in a vise with the tiny hole facing UP, you just need to snug down the vise some, not too much or you will crush the tube and the thread collar will not go back on.

Now once all that is done, you have the main part of the adapter done. The rest is up to you how you want it and how it will suit you best, I will give a few examples in the next steps and a couple bad ones as well.

Step 3: Basic

The basic adapter is just a female hose coupler screwed right on to the adapter, remember what I said about standard threads. The threads on the adapter are the EXACT same as on standard air hose fittings. Yes that is right, this means some much as well.

Here is the most basic adapter you can get.

Step 4: Qiuck Fill

Using that tire valve to fill the tank too a bit too long for me to stand there filling the tank, so I made a second adapter to just fill the tank quickly.

Step 5: In Line

Here is the final product.

Having the quick fill was nice, but it was kind of a pain to switch back and fourth between adapters to use the tank. So I made a in line adapter so I could use that tank while it was filling, plus since I kept the quick fill adapter, I can fill two tanks at the same time.

Step 6: Bad Example

This was a Big tank I converted a while back, It will hold its pressure forever, it's been at 80PSI for about 2 years now. It is a bad example, because It need a male to male adapter to fill it, and I always need to go looking for the adapter to fill it back up, such as life, I never use it because of that.

Step 7: Stock Up and Enjoy

Now go out and find some propane tanks and you will have plenty of compressed air on hand.

The tanks will smell like propane for quite awhile, but the smell does go away after several time of filling and using the tanks.

Be the First to Share

    Recommendations

    • Make it Glow Contest

      Make it Glow Contest
    • First Time Author Contest

      First Time Author Contest
    • Anything Goes Contest

      Anything Goes Contest

    38 Discussions

    i have one i want to cut in half so i can sell it for scrap- it smells like the additive they put in propane but ive had it full of water- is there any propane in there, or is it just stinky? ive already got 3 air tanks

    0
    amachinetech
    amachinetech

    Reply 3 months ago

    The fast way to get rid of the smell is about 2 cups of rubbing alcohol. Remove valve, swiril and dump in a place where the smell that lingers wont offend

    0
    noahspurrier
    noahspurrier

    Reply 6 years ago on Introduction

    It smells from the ethyl mercaptan residue they add to the propane to make it smell bad. The ethyl mercaptan stink takes a long time to go away.

    0
    SteveO6
    SteveO6

    5 years ago

    Slightly off topic, but wondering if anyone can suggest a way that I can be acertain a stanar propane tank isn't pressurized? I'd like to remove a head off of a tank that I'm 99% sure is empty. (I'm making a hank drum) I can open the twist valve, and no sound or hiss, but i believe there's a 'safety' valve that only allows a release when it's attached to a hose/stove/whatever - which I don't have. Can I take it into a home depot and just attach a hose and try the valve? Is there a special tip that engages that safety valve?

    0
    amachinetech
    amachinetech

    Reply 3 months ago

    All portable propane tanks have this little screw. Some of them are star shaped. it connects to the dip tube that shows the level of liquid propane in the tank. If you open this it will vent the tank around the float overfill protection valve. If your tank is somewhat full it will take awhile but it will get it done.

    LPG205-226x400.jpg
    0
    Big Texun
    Big Texun

    Reply 5 months ago

    The propane quick-connect has a safety valve, it won't leak unless connected. So yes, your tank may be pressurized. They stopped putting purge valves on propane takes 30 years ago, so you pretty much need to open the tank up to purge it. Try removing the quick connect fitting with the valve closed, then crack the valve outside to see if anything comes out.

    0
    heathbar64
    heathbar64

    10 years ago on Introduction

    Brilliant!! Sometimes the simplest idea's are the best. the thought that immediately came to my mind is, Why not use the newer hands free grill connector?  Of course, the whole idea is using old obsolete tanks, so probably most wouldnt have that syle of valve.  

    0
    Big Texun
    Big Texun

    Reply 5 months ago

    Don't mix propane fittings with air fittings. Mixing air and propane can/will result in explosion and death. to do the conversion, it needs to be all or nothing. If it can still be connected to a grill, someone can mistakenly try to fill it with propane.

    0
    scob89
    scob89

    Reply 10 years ago on Introduction

    I used the old style connector because it will work on both the old and new style tanks, Plus you really don't need a tool to put the old style on, I have always hand tighten mine and never once had it leak.

    On tanks the had propane in them yet, I always use the proper wrench to tighten, it's not big deal is air leaks, but if propane leaks it can have some negative effects.

    0
    glorybe
    glorybe

    9 years ago on Step 2

    This worries me a bit. Air tanks must handle moisture and normally have a drain valve to get rid of water. A propane tank may not face the same issues with moisture as propane probably has no water content. They also have no drain valve. I worry that these tanks may over time suffer loss of strength and explode. It could be very, very serious.
    Perhaps an engineer that designs air tanks could chime in on this.

    0
    Big Texun
    Big Texun

    Reply 5 months ago

    I intend to keep mine upside down and connected at all times except when using it as a temporary portable. So it should always be drained, I hope.

    0
    LeeB148
    LeeB148

    Reply 3 years ago

    Just turn the tank upside down for a minute or so and then vent the air out of the tank very quickly. If you have an air hose attached just keep it lower than the tank. This will blow the water in the tank and hose right out. Easy as pie !

    0
    scob89
    scob89

    Reply 9 years ago on Step 2

    That is easy to fix, For the smaller standard grill size tanks, I just flip them upside down about once a month and open the valve, So far, no big moisture issues or water buildup, however there is always a bit of water in the main compressor tank when I open the moisture drain

    As for the big tanks, it may be a bit harder to flip them upside down to drain them, but I have built my own air compressor system out of 4 of the big house tanks mounted upside down on the shop wall. For the compressors I have 3 motor/compressors that fill the tanks up pretty quick, and stop at 125 PSI.

    Also keep in mind that these are heavy duty tanks that hold Propane, Propane stores at over 200 PSI. I think the tanks are pressure tested at around 600 - 700PSI, Not sure on that.

    As a general safety, if the tank is pretty rust on the outside I don't repaint, instead I just replace the tank. My big 4 compressor has been working for the last 2 years with no problems at all.

    0
    owlexmyth
    owlexmyth

    1 year ago

    You forgot the 1st step, which is to make sure all the propane is removed. Adding air to a tank with propane could create the conditions necessary for an explosion. Even a little bit of propane with some air could be bad...even with no apparent heat source to ignite...there is static electricity t worry aboot.

    0
    Big Texun
    Big Texun

    Reply 5 months ago

    In my welding classes, we were told that under pressure, the flash point of a flamable gas goes down in the presence of oxygen. In pure oxygen, any liquid gas or solid that can burn may explode above 15PSI. So even oil can't be present. In air mixtures the danger pressure is higher, but only by 5 fold, so 75PSI is the explosion danger point for air.

    We were trained to first fill any tank we would be working on with water, completely full. Then drain the tank till empty. Only after that is the tank safe to work on. In welding class this meant any cutting or welding on the tank, but for the purpose of an air conversion, this would be a good practice. Water in your tank isn't a great thing, for corrosion reasons. I have a vacuum pump, so I would probably just pull a vacuum if I can find the right adapters. But when you use a compressor, water gets in with the air, so it is best to have a plan for the water. My tank conversion will be for just for storage next to the compressor, so I will just keep the can inverted to carry the water out, and before it enters the main distribution point it would flow through a water separator. Using quick connects allows quick decoupling when I need to carry.

    0
    MoiA2
    MoiA2

    1 year ago

    To get rid of the smell pour in some hydrogen peroxide 3%. Swirl it around and flush with water. Dry and the smell will be gone.

    0
    Kevanf1
    Kevanf1

    6 years ago on Introduction

    To prevent rusting on the inside of a tank just pour some auto cavity wax in the tank before you build it up. Warm the tank first then pour some liquid was inside and swirl it around. Leave it to set and you're done.

    0
    nemfield
    nemfield

    Reply 3 years ago

    Is warming the tank a good suggestion ? Boom? A lot of DIY amateurs read this, is this a good suggestion ? With all respects, perhaps a rinse with detergent ?

    0
    LeeB148
    LeeB148

    3 years ago

    Just turn the tank upside down for a minute or so and then vent the air out of the tank very quickly. If you have an air hose attached just keep it lower than the tank. This will blow the water in the tank and hose right out. Easy as pie !

    0
    Garra23
    Garra23

    7 years ago

    can you take a 1lb tank and convert it to an air tank