Can a propane tank be repurposed?

[James Mason]

I made a lube device with a standard grill size propane bottle using compressed air hookup which I welded on and a grease fill at the top where the valve normally sits. Worked great for filling differentials and the like. Very fast and convenient.

 

[Surshot]

Appreciate the idea......would be fine but this is not for spraying hundreds of feet of fence lines or tree lines etc.....way too much close in spraying that must be done on foot.

A farmer/Rancher must be inventive to work alone. Use the electric tank, put it on the tractor, 4 wheeler or golf cart, get some reinforced tuning about 30 ft long and two taper coupling joints 4 hose clamps, hook up, fill, then park and walk around. This is how I spray Coogan Grass in the thick woods, under trees.
Handy Dandy on our place is a 48 volt golf cart, modified for sporting clays and fencing. I built a 10’ PVC boom sprayer for it using a 25 gal AG electric spray tank.
It doubles as the power supply for my Wheely Bird traps also.

 

[tstex]

I get repurposing, bc I do it for a lot of diff things, esp w a 100 acre ranch, house, garage and 10-11 other sheds. However, what was good w gas in one application doesn't mean it will be safe w another that it was not intended.

Over the last 3 decades, I have owned and operated at least 20+ diff type of pressurized dispensing devices. All of them were used as the original manufacturers intended. Sometimes I didn't like how they had to work, but they worked. I also learned it's much better to spend more money on a quality product than less money on 2-3 over the same 1- yr period.

Buy quality, read reviews and go w the best one that fits your needs...

 

[pacosperson]

I will admit to my total ignorance when it comes to pressurized storage containers and could use some help. I have had no luck trying to find answers to most of my questions on the net.

Here is an idea I have had for years and wondering if it can be safely pulled off. The goal would be to have a pressurized utility sprayer that I can carry around with me for spraying roundup etc. I am tired of pumping my 2-3 gallon sprayer every several minutes. I have a 5-gallon backpack model but once full I have a hard time getting it on/off by myself and it hurts my lower back as I walk around my 6 acres. I like the idea of a smaller, pressurized, hand held 2-3 gallon sprayer. I know they make battery powered units but I like to experiment & was wondering if an empty propane tank be repurposed (refilled with air) to provide the 10 PSI that I need? I do not think the high pressure paint-ball tanks is what I want as they are thousands of PSI and expensive.

I have long wanted to take an empty (small torch sized) 1-pound propane tank and refill it with air via my shop air compressor and try out my idea. I would attach a regulator to knock down the high pressure air down to ~10 PSI.

My 1st & most important question is what PSI can these small 1-pound propane tanks hold safely? The last thing I would want is to set my shop compressor too high & have a catastrophic failure due to too much pressure while refilling it. The next question would be where can I get a low-pressure regulator with a gauge so I can dial in the PSI into my 2-3 gallon sprayer.

I've done it with a 'grill sized' tank, a submerged pick-up tube, and 80 PSI. It worked great until the inside of the tank rusted and the rust clogged my spray head. It was actually a waste of time and money.

 

[Istillcare]

Fun to play around with stuff. I do all the time, and like the sprayer most times you can buy something already made at a decent price, but then the fun factor is missing.

I did not read through all the responses and may well have been mentioned, I'd give up on the propane tank idea, not because of the danger, I don't think it would be at all dangerous, but because of the small volune and weight.

Use plastic pop bottles, various sizes 1 or 2 liter etc, free, light weight good to 100 psi, easy to work with. If worried about rupturing (I wouldn't be : ) Just put a sleeve of material of your choice around it, stocking etc. Have fun. Sorry if bottle idea already suggested I lost interest in the thread about a third of the way through.

 

[twowoode]

Many companies offer battery operated sprayers now. Why spend your time on something that won’t hold enough air for your purpose.

 

[Grumpycat]

I would use an inspected (VIP - visual inpection and hydro tested) scuba pony bottle for compressed air that has a regulator with a low pressure port on that regulator. The low pressure port would give you the pressure you would need. This combination would ensure your safety and the safety of others nearby while you use that sprayer. I would never repurpose a disposable cylinder - the cylinder wall thickness will not sustain repeated air fill ups like the small pony bottle for scuba use. It may cost a few dollars for that setup but I suspect your life and the lives of others nearby you are certainly worth much more than the cost of this safer setup.

A few dollars!

Hundreds of dollars.

The solution is to either accept the manual pump or find an electric pump that shares a battery with your cordless lawn tools or drill.

 

[Chunin]

I think the best solution for you is to just get an electric pump sprayer. My neighbor has one and he use it to spray the fence lines. Just load in into your tractor or mower cart and spray on command. It would be a nightmare to fill the tank and then pressurize it. I don't think the pressure is going to last that long before having to pressurize it again.

 

[W8BYA]

So OP i think you’d find even if you did what you initially posted, that ‘volume’ in the torch tank WAAAAY to little for what you need in 2 gallon sprayer.

I need to sincerely apologize....for some reason I stopped getting notifications when new posts were made by folks. Not mean't intentionally guys.

So I think many of you are spot on.....I think if I were to fill it with just air, even compressed, it would not equate to too much volume and not last long at all.

I suspect what I was wanting/needing was to fill an empty 1-pound propane tank with liquid air. That way as it warms and vaporizes & expands it would generate a significant amount of air volume and last a very long time.

Think about the typical 1-pound propane tank.....if you just cracked the nozzle open, that flow of propane would last for countless hours before all of the contents were empty. So I guess the question should have been can such a container be filled with liquid (chilled) air?

But that is not something I can do with a simple shop compressor and I am positive no welding or air supply firm is going to re-fill a propane container so I think I have just closed my case.

I have ordered a 3-gallon battery operated unit on a small self dolly. Says it can discharge eight 3-gallon fillings on one charge. I think this was the safest & most expeditious route. TU everyone for their input.

 

[pcman]

So everyone who refills their propane tanks with a larger propane tank is at a high risk of killing themselves?

I will admit to my total ignorance when it comes to pressurized storage containers and could use some help. I have had no luck trying to find answers to most of my questions on the net.

Here is an idea I have had for years and wondering if it can be safely pulled off. The goal would be to have a pressurized utility sprayer that I can carry around with me for spraying roundup etc. I am tired of pumping my 2-3 gallon sprayer every several minutes. I have a 5-gallon backpack model but once full I have a hard time getting it on/off by myself and it hurts my lower back as I walk around my 6 acres. I like the idea of a smaller, pressurized, hand held 2-3 gallon sprayer. I know they make battery powered units but I like to experiment & was wondering if an empty propane tank be repurposed (refilled with air) to provide the 10 PSI that I need? I do not think the high pressure paint-ball tanks is what I want as they are thousands of PSI and expensive.

I have long wanted to take an empty (small torch sized) 1-pound propane tank and refill it with air via my shop air compressor and try out my idea. I would attach a regulator to knock down the high pressure air down to ~10 PSI.

My 1st & most important question is what PSI can these small 1-pound propane tanks hold safely? The last thing I would want is to set my shop compressor too high & have a catastrophic failure due to too much pressure while refilling it. The next question would be where can I get a low-pressure regulator with a gauge so I can dial in the PSI into my 2-3 gallon sprayer.

 

[pcman]

I will admit to my total ignorance when it comes to pressurized storage containers and could use some help. I have had no luck trying to find answers to most of my questions on the net.

Here is an idea I have had for years and wondering if it can be safely pulled off. The goal would be to have a pressurized utility sprayer that I can carry around with me for spraying roundup etc. I am tired of pumping my 2-3 gallon sprayer every several minutes. I have a 5-gallon backpack model but once full I have a hard time getting it on/off by myself and it hurts my lower back as I walk around my 6 acres. I like the idea of a smaller, pressurized, hand held 2-3 gallon sprayer. I know they make battery powered units but I like to experiment & was wondering if an empty propane tank be repurposed (refilled with air) to provide the 10 PSI that I need? I do not think the high pressure paint-ball tanks is what I want as they are thousands of PSI and expensive.

I have long wanted to take an empty (small torch sized) 1-pound propane tank and refill it with air via my shop air compressor and try out my idea. I would attach a regulator to knock down the high pressure air down to ~10 PSI.

My 1st & most important question is what PSI can these small 1-pound propane tanks hold safely? The last thing I would want is to set my shop compressor too high & have a catastrophic failure due to too much pressure while refilling it. The next question would be where can I get a low-pressure regulator with a gauge so I can dial in the PSI into my 2-3 gallon sprayer.

 

[pcman]

Too much trouble to rig the fitting to charge it ,the propane tank will blow up drilling for the air fitting.The Xtra weight of a steel tank filled with water would be super heavy and very little room for air .I got a 13 gallon at tractor supply set it on a zero turn and clamp on batt. of the mower, my wife does all the spraying now and I just mix and doing the mowing.

 

[EdinLa]

Why didn't you just take that 5 gallon backpack sprayer you said was too heavy and made your back hurt, and put 1 gallon in it at a time? ....I really like backpack sprayers with hand pumps because you are ALWAYS in control of the pressure and can minimize waste while avoiding contact with the sprayed chemicals. ....My old barn is full of all kinds of sprayers that don't get used, while I use a pump up 2 gallon hand sprayer and a good 4 gallon backpack sprayer.

 

[W8BYA]

W8BYA,

All pressure vessels have a rated lifetime for a reason, to keep people safe from Rapid Unscheduled Disassembly ( thank you Elon Musk ). There is a date stamped on the side of the 20+ Lb propane cylinders and pressurized air storage tanks to prevent it from being refilled after that date and the 1 Lb bottles are built for single use/ single fill only. That is also why the connection on 20+ Lb bottles has been periodically changed to prevent the continued use of older cylinders.

HF does make a connection that would allow you to fill a 1 Lb bottle but you are playing with a hand grenade that may or may not go off. Air pressure tanks have a valve to remove ( blow off ) water that accumulates so as not to compromise the tank by causing internal pitting/ rusting. 1 Lb cylinders have no means of getting rid of water.

Here is propane vapor pressure graph ( log scale ) but I have no idea what the schrader pressure relief valve on top of the 1 Lb bottle is rated for.



View attachment 752951

Here is a possible non exploding solution

View attachment 752953

As I read all these new posts I have not yet seen (for some reason I stopped getting notifications & I thought the thread had died) lots of thoughtful & helpful suggestions etc.

I know it is easy to miss one or two when many posts are made. I cannot use my tractor or even Z-turn to hold a sprayer. For large jobs like along my 1200' tree line and when I had an open cab NH I put a battery powered 25 gallon sprayer in the bucket and could spray all day with ease. That worked great. I can't drive a Z-turn and spray at the same time (not proficient at driving the Z-turn with one hand). I was going to mount that 25 gallon sprayer on the front of the Z-turn.

But my property has changed over the decades.....lots more small trees, radio towers, flower beds, and countless sharp turns etc. Thus using a larger tractor is completely out of the question. Simply no way to maneuver around tight places. Plus now I have a closed cab tractor ! And as noted I have not mastered steering my Z-turn with one hand while spraying with my other hand.....I can do it but it is extremely awkward and VERY slow.....so that route is out. What is left is me walking around with a sprayer.

Small hand held 1-2 gallon sprayers are out since I have a bad lower back and walking back & forth to refill every 15 minutes will not cut it. I am toast after several trips back and forth over my 1200' lot. I do have a backpack sprayer that works fine but again my lower back surgery did not go well and I find walking around with 5 gallons for more than 15 min or so to be painful. plus putting it on when full by myself is not easy.

Thus as stated in my previous post I settled on trying a 3 gallon battery operated unit. 3 gallons may just be enough to let me get enough spraying down before I need to refill it and I like that it rolls on wheels. This will let me get around all the intricate and close quarters around the house, barn, etc with ease. I will report back to everyone how well it worked or did not. The unit is made by Scotts.

Again, I want to sincerely thank everyone for jumping in and sharing their thoughts and ideas. A wonderful group we have here. Thank you !

 

[GGray]

If you are trying to make a small, lightweight, tank to carry you can use PVC pipe. Keep the pressure below 150 psi and you will not have any issues with failure. The one caveat to PVC is it gets brittle with age and can fail. I'd replace the tank every few years to prevent that.

Please do not suggest such a dangerous idea

 

[W8BYA]

When you refer to a one pound cylinder, are you talking about the little disposable propane tanks?
As others have said, do yourself a favor and just go buy a small tank. Roundup is caustic and trying to compare it to an air tank is like comparing apples to rock salt.

At this point it does not matter as I have ordered a dolly type battery powered unit......but, the original idea was to use a pressurized air cylinder with valve and regulator, attach a hose to it, run the hose into the top of a plastic sprayer container (well above the liquid level) and have a traditional hand-pump sprayer w/o ever having to pump it up.

I would have added several extra safety pressure relief valves in the top area of the plastic container as well just to make ensure the inside pressure never saw more than 15 or so PSI. I have seen OEM rate their plastic vessels at around 25 PSI so 15 PSI would have been quite safe.

Thus no chemicals in the pressurized metal tank or anything like that. If propane was not exposive I would have tried this a long time ago......To visualize the setup picture this (I would never use propane but am using it as an example simply for illustration). Take a typical propane torch and JUST crack the valve open so you barely have a small steady flame. I would have used that tiny amount of pressurized flow to keep the plastic spraying container charged at all times during use. When I am not pulling the trigger releasing chemicals and the pressure builds up to the 15 PSI point the 2-3 safely relief valves I installed would be constantly venting the excess pressure. But again, I wanted to substitute pressurized propane with pressurized air like in a 1-pound bottle. But again, all a completely moot at this point, but that was going to be the idea.

 

[bgr]

I will admit to my total ignorance when it comes to pressurized storage containers and could use some help. I have had no luck trying to find answers to most of my questions on the net.

Here is an idea I have had for years and wondering if it can be safely pulled off. The goal would be to have a pressurized utility sprayer that I can carry around with me for spraying roundup etc. I am tired of pumping my 2-3 gallon sprayer every several minutes. I have a 5-gallon backpack model but once full I have a hard time getting it on/off by myself and it hurts my lower back as I walk around my 6 acres. I like the idea of a smaller, pressurized, hand held 2-3 gallon sprayer. I know they make battery powered units but I like to experiment & was wondering if an empty propane tank be repurposed (refilled with air) to provide the 10 PSI that I need? I do not think the high pressure paint-ball tanks is what I want as they are thousands of PSI and expensive.

I have long wanted to take an empty (small torch sized) 1-pound propane tank and refill it with air via my shop air compressor and try out my idea. I would attach a regulator to knock down the high pressure air down to ~10 PSI.

My 1st & most important question is what PSI can these small 1-pound propane tanks hold safely? The last thing I would want is to set my shop compressor too high & have a catastrophic failure due to too much pressure while refilling it. The next question would be where can I get a low-pressure regulator with a gauge so I can dial in the PSI into my 2-3 gallon sprayer.

Sounds a bit complex to set up for a backpack sprayer instead of using the rechargeable backpack ones. But, there used to be kits for sale to convert grill-type propane tanks to portable air tanks. You got a screw-in manifold with a hose, fill port for tire chuck, shutoff valve, and pressure relief valve. Relief was set for 125 psi.
The propane tank was ok as long as not rusted inside. You can find a kit on line. Those are probably what you see on You Tube. I have used them and they work, but the propane tank is a bulky shape to carry around.
Harbor freight makes an incredibly light weight aluminum air tank. Good to 140 psi. Better shape to carry. I got one to replace a steel inflator tank last year. No rust and unbelievably light to carry. You should look at it.
Probably an electric rechargeable 2-3 gallon sprayer would be simpler for you. Take a good look at what is available from the good brands.
Most of the grill size propane tank fires and explosions were caused when tank was heated by sunlight when carried in a car. The tank would heat, pressure would rise, the relief disc in the tank would release gas into the closed environment in the car, and something would ignite the gas, causing an explosion. Or, someone would store the tank to close to a heater or furnace. Tank would warm and release gas, and the appliance pilot would light it.
You don't have an explosive gas in a grill cylinder when using it as an air tank. Just be sure to ventilate first to get all gas out before using it for air.
To get a cheap 12v compressor which can put out some air, you could try to get a junkyard air shock/suspension air pump at a junk yard. Might even come with a small pressure tank.
If you have rechargeable tools, what kind of tire inflator is available for your brand of battery. Makita is excellent and might do what you want.
if you are talking about putting 100 psi air from your tank into a sprayer, all you need on it is a tire valve installed and an air pressure gauge on the inflator you are using to fill from 100 psi source. You can watch the gauge and stop at the right pressure.
Good luck with the project.

 

[W8BYA]

Why didn't you just take that 5 gallon backpack sprayer you said was too heavy and made your back hurt, and put 1 gallon in it at a time? ....I really like backpack sprayers with hand pumps because you are ALWAYS in control of the pressure and can minimize waste while avoiding contact with the sprayed chemicals. ....My old barn is full of all kinds of sprayers that don't get used, while I use a pump up 2 gallon hand sprayer and a good 4 gallon backpack sprayer.

The answer to your question is because my property is a little over 1200' long and hundreds wide.....if I only filled it with one gallon (which I have tried) I would be spending tons of time walking back and forth to refill it.

With my back issues I am not able to make the many required trips all over my property and keep refilling.

Appreciate the thoughtful idea but it will not work here (for me). As mentioned, I will now try a hand pulled dolly 3-gallon sprayer and see how that works. Do not own a small traditional garden tractor with steering wheel, golf cart, 4-wheeler etc.....so it's either my Boomer 40 (which is like turning an aircraft carrier inside a marina) or my z-turn. Neither of which can be used in the close-in areas I need to be spraying most of the time.

 

[W8BYA]

Many companies offer battery operated sprayers now. Why spend your time on something that won’t hold enough air for your purpose.

It was a thought experiment. I like tinkering and DIY & repurposing things that's all. I was just on a fact finding mission wanting to get opinions, facts, and even learn something along the way. I'm smart enough to know I am ignorant in many areas which was the reason for my post. Thanks !

 

[Bavarian]

Why would you play with a propane tank? Go to a wrecker and get an air tank off a semi truck. All kind of shapes and sizes are available with standard connections for air lines present. They run on higher pressures than your domestic shop compressor will provide.

And no, they do not explode when they rust through. They just start to leak.