Turn the can upside down. That will prevent a lot of the fluid from coming out. If the can is designed to be held upright to spray then turn it upside down to refill. If the can is designed to be used upside down, then turn that can right side up to refill the air pressure.

To add a bit to your post, the propellant in aerosol cans has evolved a bit over the years but it has never been air. In the beginning, it was R12 refrigerant. Obviously, this was curtailed with the whole ozone hole thing. The huge advantage of R12 is that in the can, it was partially liquid and partially gaseous. As the product was used, some of the gas would leave and then the liquid part would boil off to make more gas. As this happened, the cans would cool since the refrigerant was doing it's thing. More recently, CO2 has been used to avoid the greenhouse gas issue. Side note, I worked in a can research department of a major steel company, and I was the first one to find a way to use a can with a welded side seam as an aerosol can. If you look at the weld on your can, note the darkened area where the weld occurred. I figured out how to do that consistently in a way that could hold about 130 PSI safely.

I’ve been doing this for years without anything but a rubber tipped air inflator. Works perfectly, obviously you should take all the precautions the man showed you. Reminder to those who say just buy a new one "a penny saved is a penny earned”……

Genuinely useful and REAL - unlike other silly "tips and hacks". Thank you !!

Sir, this is an excellent video. I've been recharging my depleted aerosol cans for years with a rubber tip on my air gun but your idea that incorporates a tire stem is brilliant. The safety shield made out of the spray can cap is also brilliant. Thank you for sharing this,

This is actually pretty awesome advice. Usually when people talk about stuff like this on here I see them drill a hole in the can and add the valve directly to it lol. All well and good if you want to keep reusing the can but tedious as hell to keep doing on new ones all the time if you use a lot of cans.

Love it!!! You're both saving money and saving the environment! Saving green is often saving green folks. Repair when possible and logical.

REALLY GOOD JOB!!! You took your time and *MOST IMPORTANT* you covered all the SAFETY AREAS! All that makes you a *FAVORITE CHANNEL* !!!

I was thinking using CO2 from a tank I use for homebrewing might be a better choice especially for paint cans. Great video and thanks for the link for the Tire Inflator with pressure gauge!

Love your videos. Finally a KZfaqr that knows how to deal with every day situations.

This is awesome. I bet if you fill the can while it's upside down, you wouldn't have hardly any mess spraying out. Mount your valve stem in a vice or something and just press the can down on it.

Good safety tips as well as good information!

WD-40 is renowned in my experience for losing can pressure. Almost every can I purchase loses pressure over about a year on the shelf. This looks like it's worth a try. Thanks!

You can do this with a foot pump or one of those small electric air tyre inflator pumps, you might not get the same pressure but in most cases will work good enough.

thank you, especially for emphasizing the safety equipment. Well produced and easy to understand

Dude, you're a genius. I've tried doing this with just the air hose and that wasn't ideal, ugh. Your solution is great, I have extra tire valves and can caps.

Great hack! I just got a can of WD-40 that stopped working b/c of no propellant. You are very methodical and clear in you explanation, thanks 👍

always wondered if i could save my cans somehow, great video thanks man

Very interesting and useful. I throwing away dozens of these cans of various type because of the lack of pressure. Now I have a solution and thank you ❤🙏.

I like that you include your original ideas along with your improved ideas. One thought would be to set the whole assembly down inside a piece of scrap PVC pipe. This might help with limiting the blowback mess and potential damage if the can did decide to give way. Kudos on stressing safety. Well done!

Brilliant, excellent idea. For those living in cold climates - make sure that your can are at upper room temperature when you use them - as air expands, it cools the can and you loose pressure. Keeping the can warm (not hot if it is full, it can burst) will extend the air pressure you get out of it. Great video of a very common problem, Ciao, L

I have been doing this for a long time just using a rubber tipped blow gun. You do not need to depress the nipple on top of the can, the air pressure opens the valve and I rarely lose any product unless the seal I make between the tip and the can allows some to escape.

Great job sir. I literally have five cans like this. I never threw them because they all have alot of product. One parts cleaner is completely full.

I keep an old piercing style can tap for small Freon cylinders. Pierce and lock to the top of the can then feed it air as you like (matching fittings are cheap if you don't have an old AC gauge set lying around and you can use compressed air fittings to basically turn the can into an airbrush). The tap can also drain liquid from the bottom. I remove the valve from the piercing fitting so it's just a straight shot.

Good tip, thank you for the demonstration, and good suggestions for better success.

That was one of the best videos, love the idea with the splatter cap. I'll give you a "98", my 2 per"CENTS" is a rag underneath the cap while repressurizing. Wish they filled them from the factory with one of those basketball needle valves on the bottom. Thanks for sharing 😊

awesome man!!!! thank you for sharing that! I need to do it as well i have so many cans with no air.

I always thought I had the best ideas but this one is something I never thought of. You earned a Like and a sub! I can’t wait to see what you do next. I have been looking for a air inflation device like this. As long as it last. I hate buying the same tools over and over again.

Outstanding, very informative.

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This is a really good channel! Thank you for sharing your knowledge and hard work.

Just saw this. Gave it a thumbs up. Looking forward to seeing more videos before I subscribe. I’ll definitely use this. I especially liked the spray can top modification

The number of safety precautions and references to SDS, rubber gloves, shields, disclaimers etc. I appreciate the tip, I will save numerous partial cans going forward. Most cans will not produce so much overspray if filled upside down. The pickup tube inside the can runs to the bottom of the can, when inverted the pickup tube will be in the empty portion of the can. Right side up and the pick up tube is down in the solution causing the back spray.

Excellent detail extra step appreciated bro thanks. 👍

Nice, I've seen this trick before but I like the better gauge idea and after seeing what you did, I'll try that with an older tote and cut an area out for one arm to reach in.

Very good and easy meethod. If you could somehow fill the can by holding it upside down while pressing air it would just spray out only a small amount of liquid for a second and then just take air without any spit

Never knew those cans could take so much pressure. Great video sir.

Great video very informative especially pointing out the different sizes and shapes of nozzles on each different can. I was wondering if this would the same way on the compressed air cans like you blow off the computer with or if that would not work because it has separate chemicals in it? I also had a suggestion you might try as far as the overspray when you make a shield for the valve, possibly cut a large enough hole in a plastic soda or water bottle for any size can to fit through or cut the bottom off completely to desired height & either place it on top of a old towel or rag that would absorb the overspray or cut the bottom off of another plastic bottle & place a towel or rag inside it to catch the overspray & still allow the excess air to escape when placing the two together. Use the top half the bottle including the lid screwed on tight, with a hole cut in it for the valve and the valve pulled through it, place the can resting on the bottom part of the cut out bottle, then place the upper part of the cut out bottle that has the lid screwed on tight with the air valve through it and connected to the air compressor nozzle on top of the towel, rag or cut out bottom part of the plastic bottle with the towel rag inside it leaving a slight air gap between the top and bottom plastic as you pressurize the can.

Man that worked GREAT!! Thank-You so much.

Thank you for this Family!!! PEACE and God bless.

it is a lot easier to just use a blowgun with a rubber tip just set compressor regulator to 80 or 90 if you are worried about it being too high the cans are rated for way more pressure than the can comes with.

Here's a safe tip: A can that is nowhere near full, also does not need a full pressure spray. Only need to add about 30 lbs of air pressure to use up the excess. Be safe, don't add 90+ lbs of air to a near empty container. That lbs is for a new can. Be safe, don't use more pressure than needed. You get a lot more air in the can since it's not full of liquid. You don't need that high amount of dangerous pressure

Very smart! you just made my spray paint workable again.

I "refill" my no-pressure cans by making an adapter between the target can and a can of Dust Off ("canned air"). Connect the 2 cans with the Dust Off upside down and press both spray valves. Some of the liquid from the Dust Off will be forced into the target can and will act as the missing propellant. Much easier and more long-lasting than using compressed air.

I knew this was possible, but I wasn't sure how to charge the cans. Thanks for making this video, as I will make sure to remember it for future reference.

Such a satisfying sound when filling them up lol

This is actually a great idea, i have tossed too many half cans of WD40 because the air ran out. Thanks for giving out this great info, now instead of tossing out thise cans i will just put more air in them.

Great idea, and as seen it can be perfected like as we were shown with the cap instead of the face shield splatter protection. I’m thinking this can be modified for the valve to can also to reduce or even eliminate the splatter at the charging point, like an o-ring seal inside the tire valve. This is a great idea also for reusing the can because if air can be added, so can the desired fluid in the can. Hack at least and probably this man’s idea is a money idea… patent it Sir, “QUICKLY”…😊

Great trick for if I ever buy an air compressor.

Did this the other day but used a 20 dollar cordless Bauer pump used the tip for pumping up balloons pushed down on the plastic tip pumped it worked like a charm I was amazed 😊

Great idea thank you. I'm going into the garage right now.

Regular air might affect the product. I use butane to recharge cans since most in my neck of the world they pressurize with butane. I use fine brass tubing to bridge the tips of the cans together.

Great idea. I never thought if doing something like this before, but next time i run across a lame can I'm definitely going to try this. I wonder if my air compressing kit came with a nozzle i could use. I also have compression testers for engine cylinders, radiators and for filling radiatirs and they have pressure gauges on them

I love that this is all stuff I already have. I even have spare valve stems from a previous project. And even if I don't need it (I do in this case) I am a big fan of "Micky Mousing" stuff. Time to get that half-full can of primer back!

Thanks for the tip. I purchased the items you showed and I know I have a couple of cans I need to repressurize

Incredibly dangerous info. 😂 💥🎉 Well done. 👍🏼

Great hack and i'm very impressed with the attention to safety.

Totally awesome a game changer a great winner all the above

Very good! Going to have to try it!

With the WD - 40, it's a good idea, but with paint, not so much. Paint will dry out with air. Needs CO2.

Great video, thanks! Harbor Freight just added a red pressurized spray container where you can buy from the WD-40 liquid in a 1 gallon container, not an aerosol, put it in their spray container and the use an air compressor to charge the container with air and never have to buy an aerosol can of WD-40 again and worry about loosing the aerosol pressure again.

Awesome hack, thanks a bunch!

i just drilled my cheap blow gun out to same as the cans plastic spray pin .i put a quick blast of 100psi and good for a few days again because can valve is usualy faulty . good video and a safe way of doing it. also very good at stopping so much waste going into land fills .

Place the can in a cardboard box with top lids cut off along with cap shield as described for keeping overspeay contained.

WD40 is notorious for not spraying when still full.

I have watch 3 of your video. I have subscribed. Keep those videos coming👍🏻👍🏻👍🏻

Good instruction! Thanks for sharing!

I did something similar with a can of Fix-a-flat, but I used an over-inflated tire to put about 45 pounds in it, then used it to seal an under-inflated tire with a rough bead. With any of these methods, it makes sense to use up the contents of the can quickly, since most of these products were not intended to be propelled by air.

Great idea! I will try it. I usually punch a hole in the can and drain the liquid into a manual spray bottle.

Great video! Thanks for posting.

simply brilliant !

Would that work with an electric tire compressor? They stop off when pressure is reached.

Should we think about how a mix of compressed air and flamable liquid confined inside a can might behave? Perhaps nitrogen, carbon dioxide, or other non-oxidizing gas was used originally. Take care.

Very creative and I found this video as a interesting learning experience. Great job and thanks for sharing your knowledge.

Bad ass! and good looking out with the safety measures! Cheers!

Set your compressor pressure regulator to 50 to 55 psi. Its enough to re-charge, and makes it impossible to over-pressure the can to a danger level.

Awesome tip. I actually never thought of recharging aerosol cans. And I was just cleaning my garage yesterday going thru all the cans and cleaners that lost air! I'm a fan and new subscriber now.

fun video, thank you for sharing it and your time!

Thank you so much for explaining this. It does save you money on dead airasal cans.😮

Really liked the video and the clear way you communicate. Not sure if this was asked yet, but can a bicycle hand pump be used?

If you don't have the compressor and accessories, it's cheaper to buy a new can. If you don't have a workshop that you can make a mess of, it's cleaner to buy a new can. If re-pressurizing is not for immediate use, normal air can damage the product inside the can and it is better to buy a new can. Buying new is sure less environmentally friendly, but the idea you suggest is so unnecessary and a waste of time and energy. But if one going to do what you suggest, it's better to turn the can up side down while filling. It's a lot less messy

You have some good tips

I have everything necessary on hand to do this, including the aerosol cans. Gonna try it today.

Don't use this method of you need predictable results like you get from a fresh can of paint. It is a good tip for other spray cans that don't need consistent pressure. For spray paints, a butane refill works better. Compressed air isn't what's used when the cans are filled at the factory. The propellant is something that's a gas at room temperature but a liquid under pressure. As you spray and use up the paint in the can, more propellant evaporates inside the can to maintain the pressure. The pressure in the can is determined by the vapor pressure of the propellant, so it stays constant as long as there is propellant in the can. Compressed air doesn't liquefy at a temperature or pressure useful for spray cans. It remains a compressed gas, and the pressure goes down as it expands to fill the space in the can when you spray. With compressed air, you need to put in a little more pressure than needed so that the pressure doesn't drop too low as soon as you spray a little. But you don't want so much pressure that the paint doesn't spray correctly. Typically, if you run out of original propellant, there isn't much paint left in the can. So one filling with compressed air will let you use up the contents. If you manage to empty the propellant on an almost full can (like by spraying with the can upside down), you might need to do several fills with compressed air to keep the pressure in a good range for spraying. You won't be able to overpressurize with a butane refill because butane vapor pressure isn't that high. With an air compressor, around 70 psi is optimal (it's a little more than what's needed). If you exceed around 90 psi, it may affect the quality of the spray, or possibly rupture the can.

2 variables to consider. 1) some cans may have check valves 2) a lot of cans don’t have a nipple coming out. The nipple is on the nozzle. Could probably fabricate something to accommodate those.

A thoughtful video my brother,thank you

Hi, I've wondered about doing that years ago when can's didn't "spray" when they should that still had fluid left inside the can. Thanks for your video about this hack, I should have done it years ago when I first thought about it., cheers, Teddy

Extremely practical ! Thanks.

If you put air into a paint can th air will solidify the paint th company uses prop and or butane

Childs play. I used to refill "flick-flint" butane lighters from the aerosol cans the bulk fluid/gas came in. Same principal although the lighters used a safety mechanism (in the exit valve) which meant the process of refilling them, was a lot more complicated. Still, I not only refilled them I also had new flints to re-flint them with too, thus re-used many before they simply fell apart.

Cool hack! Thanks for sharing.

Really...you are only the one who suggest to wear PPE thanks a lot

When using the protection cap, you need to make sure that the chemical from the first can doesn't interact with the chemical with the next can.

Too much outlay and hassle to fill half spent cans!

Thank you for posting this I learned something at my age

If this fails and you're sure its out of propellant, you can knife open the cans and get the liquid out. Ive done that for WD 40. Really smart thaanks!

Compressed air has water in it. As far as the paint goes. What about the water in the air your putting in the can?

Mmmmmmmmm ……I think I’ll just take the loss and buy a new can!!!

Very clever. Thanks much.

this was very usefull! i go try this now. thanks! less waste this way.