An Ask Uncle Dave How-to
Build Your Own tubeless Inflator
Like all great ideas, I was not the first one to come up with this one. That is to say, I did think of it all on my own, but as I planned out the project and finally thought to plug "fire extinguisher tubeless tire inflator" into Google, of course a bunch of people had already done it. But somebody else made a hamburger before Ray Croc put a McDonald's on every corner. So what I'm giving you here today is kind of the Dairy Queen of tubeless tire inflators: I'm not the first to market and I'm giving you a suspect product, but I am packaging it up and distributing it to a mass audience, and some people may see fit to consume it, but many others won't.
Why bother?
Yes. Why bother, indeed. There are so many products out there that let you seat a tubeless bicycle tire with ease. You have the Bontrager pump (US$150). The Airshot device (£50). Specialized (US$55) and Schwalbe (US$75) are doing things. Shit, you probably have a bloody air compressor that is free to use down at the local gas station. But there are two things going on here that are driving me to build this thing:
1 - I'm way too cheap to spend that much money on a ready-made product.
2 - I'm developing too many excuses for having bad tires on my bike.
So I was sitting around one day thinking that it would be great if I didn't have to drive down to the gas station every time I wanted to change tires. And then drive back again once I'd finally fixed the problem that caused things to not work out the first time. And I thought that it would be really great if there was a readily available pressure vessel with an easily controllable valve attached to the top. Something like, oh I don't know, a fire extinguisher? So here we are. If that's not good enough, we can pretend that somebody asked a question about this.
Step 3 - Clean out the extinguisher
Everything should unthread fairly easily. Take the hose off the front. Take the pressure gauge off. Then screw the valve body/head off of the extinguisher. Give it all a good rinse out.
Step 4 - Wander around Home Depot like an imbecile
This is where you're going to want to have selected the right fire extinguisher. My master plan saw me strutting into Home Depot, finding a nice threaded hose barb and slapping it on in place of the hose. Of course, nothing fit, so I ended up buying a large bag full of fittings so that I could scab together a two pound mass of brass that would allow me to mate the stock hose with my pump head. I finally tracked down the various thread pitches and diameters for the valve body of my fire extinguisher, so I may eventually order the proper M16x1.5 Hose Barb that I will need to clean things up.
Other things you're going to need:
An old Presta or Schraeder valve - I was actually hoping to do a Schraeder valve so that I could easily fill this thing up down at the gas station, but I didn't have a threaded version. You'll need something that you can tighten down with some force, so a Presta will probably be your best bet.
A pump head - I bought a Park replacement head off of Amazon. I was planning on just trimming the end off of the hose and using that, but I decided I'd rather keep the tube whole and use it for a spare on my pump.
3/8" OD/1/4" ID Tubing - If your pump head doesn't come with tubing, you may need to buy some. Supposedly the white polyethelyne tubing found at Crappy Tire is good to 100 PSI, but I'm not going to be surprised if I end up replacing it fairly often. Braided vinyl would probably work really well if you can find it.
Teflon Tape - If you're using NPT fittings, you're going to want to give all your threads a good wrap of this. It's super cheap so don't skimp out.
Hose Clamps - Because nothing will fit, otherwise.
If you're smart, you can probably keep your total out of pocket expenses below $20. If you're not, you're going to buy a whole bunch of crap that you don't need and wish you just bought something ready-made.
Step 5 - Attach your Presta/Schraeder Valve
There's many different ways you can do this. If there's a fill port on your valve body, you may want to go in from there. I decided to just drill a hole in the side of the extinguisher. It was remarkably easy to get through, just make sure you use a center punch to mark your hole and you should be fine.
Once your hole is drilled, use some string to feed the valve through the hole. Make a seal using some of the inner tube that you cut up, throw a washer or two on top of that and tighten the whole thing down. Then take it apart and seal it up with some tubeless sealant or some shoe goo once you discover that it leaks like crazy.
Step 6 - Attach your hose
Once again, if you were smart with your fire extinguisher selection, it's going to really pay off here. All you will need to do here is thread your hose barb onto the head of your fire extinguisher and then jam your hose on and finish it all off with a hose clamp.
If you weren't smart, this is where your life starts to suck. First, you'll have to chop the fire extinguisher hose up. Make sure you do this in the kitchen, using one of your cutting boards. They probably have tumeric stains on them already, so it should be fine.
After that, grab your monstrosity of a fitting and spend a good hour wrestling it on to the end of your hose. It's like jamming a cucumber down the urethra of a flaccid penis. I would imagine. No fun. No fun at all. WD40 helps, as does clamping the whole thing down so you can get some good leverage (once again, make sure to use your kitchen counter). I never did get it all the way on though, and just tightened my hose clamp up really tight.
And of course, the polyethylene tubing had the opposite problem, and needed a few good wraps of gorilla tape to pad out the diameter a bit. Once completed, the whole thing is hideous, but seems like it probably won't kill me.
Step 7 - Fill 'er Up
That's really all there is to it. Use your floor pump or the local gas station to fill your gizmo up to 100 psi or so, and give it a rip. Here are the videos of me trying my unit out for the first time. Both involved nothing fancy, no soap on the beads and no valve stems removed or anything like that. I just mounted the tire and gave it a rip. Watch the first video and you can hear my surprise at the end that the whole thing worked so seamlessly.
The second video is after I popped the bead off and added some sealant. I also went up to 110 psi in the fire extinguisher and you can hear that I got some really nice bead pops. Once complete, everything equalized to around 35 psi, so you can really only get one tire at a time unless you want to put a whole bunch of faith into your craftsmanship and really up your pressure.
Uncle Dave's Music Club
We've pushed over 1600 words, with several photos and a couple of videos. Do we really need to keep this going?
And because this wasn't a real question - no prize for you. If you have a good question for Dave - or maybe something that will give him another DIY project - send it to him here...
Comments
edulmes
7 years, 6 months ago
Props for the DIY ingenuity, but for that price, I would just go and buy a Harbor Freight 5 gallon portable air tank, like http://www.harborfreight.com/air-tools/air-compressors/5-gal-portable-air-tank-69716.html. About the same price and no cucumber jamming. Also has a fair bit more capacity, so you might be able to do multiple tires with one fill.
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tashi
7 years, 6 months ago
IME I can do about a half-dozen co-operative tires with a 5 gal Air Pig, fewer if they're being testy. They're a good choice for those that don't want to buy a compressor or spend their time with this (clever) hack.
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Dave Tolnai
7 years, 6 months ago
Oh. Sure. If you want a readymade solution that holds more air and doesn't require messing around with crazy fittings and probably won't kill you.
http://www.princessauto.com/en/detail/5-gallon-portable-air-tank/A-p8474868e
It's not red, though.
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rvoi
7 years, 6 months ago
Yellow means proceed with caution. Red designates this will likely kill you at the first error.
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fartymarty
5 years, 3 months ago
I have also seen this done with a 1.5 litre soft drink bottle if you are really going budget.
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ExtraSpecialandBitter
7 years, 6 months ago
I thought Teflon tape was just meant to lubricate the threads so that they can thread tighter. NPT is tapered and is an interference fit, so the further you thread the better the seal. It also prevents galling and so the thread surfaces remain smooth and less potential for gaps. Too much teflon tape can restrict how far you can thread onto the fitting and that means less thread overlap, which weakens the joint. Although 100 psi is pretty low, so I think you're fine... even if it's not done correctly.
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Mammal
7 years, 6 months ago
I have found that some brass NPT threads don't want to seal, no matter how tight you make them. Teflon tape usually solves this.
You're correct on the theory though.
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Dave Tolnai
7 years, 6 months ago
Ya. Not a plumber or a pipefitter, but I've always gone with the rule that if there isn't a seal or an o-ring, use some teflon tape. Makes sense from both a lubrication and a take-out-the-imperfections perspective.
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Cameron Curtis
7 years, 6 months ago
I like it. I appreciate the long hose. If it were me I'd have made it longer and hidden around the corner as certainly my skills would have meant bits blew apart. Speaking of blowing apart very interested in what wheels those as cb's are known to do just that, but they do look a treat and if newer iterations are more trustworthy I think they're just the fashion piece to compliment my ride where again there are some highly suspect skills.
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Dave Tolnai
7 years, 6 months ago
I knew somebody was going to bring up the Crank Brothers wheels. Those wheels are a few years old, but I haven't run them consistently. I ran them for a while on the Ghost test bike that I had, and then I moved them on to the Devinci Spartan once I finished up the Deore XT test. They've got a good year-and-a-half of old guy who doesn't ride enough use on them. I know they have a bad reputation, but honestly, they've been flawless:
1 - Totally sealed. No rim tape to worry about. Honestly, that tire swap that you saw the end of in the videos was ridiculously easy, and they tend to hold air really, really well.
2 - Super easy maintenance. Freehub bodies swap really easily (although are reverse threaded, which it took me a while to figure out) and I've seen a wheel build done in about 5 minutes. Spokes are super easy to swap, if need be, but I've had some pretty direct hits to a spoke and none have broken on me.
3 - They're still running straight.
4 - I don't know how to say it any other way, but they feel really light.
Faults? They could be a bit wider, but the newer generations may have caught up.
It's really too bad that they wrecked their reputation with their initial launch, because I've been pretty happy with them.
I was also thinking about the hose when I watched my video. Sort of "I probably shouldn't have had my face that close to everything". But the pressure through the hose and at the wheel never got above 35 psi. I think the worst that would happen would be a hose blowing off a fitting. There should be far more worry at the presta fill valve on the bottle, which is seeing the full pressure.
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Tuskaloosa
7 years, 6 months ago
Hahaha nice write up I like the fact that you included all the frustrations and 'learn-as-you-go' tidbits. Contemplated making one just to satisfy my inner DIY ego... but life is too short really, plus my missus would promptly refer me to the other several DIY projects that really need doing!. Having said that picked up a used Airshott for 35 quid recently.
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Dave Tolnai
7 years, 6 months ago
It's like the guy who keeps writing about caramelized onions taking longer than 10 minutes to make, even though that's what every recipe says. There's nothing worse than a how-to that glosses over the difficult bits, or lies about how long things will take.
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norman
7 years, 6 months ago
15 minutes though and you can get pretty close
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Shrockie
7 years, 6 months ago
Great Hack Uncle Dave!! Schrader valves can be picked up that pop into auto wheels, the're pretty solid.. also, some fire extinguishers have a valve on them.
Side note.. That extinguisher also makes a helluva squirt gun.. Fill it 2/3 with water so 1/3 can compress the air.. You can fully soak someone in 5 seconds.
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[user profile deleted]
7 years, 6 months ago
This comment has been removed.
Dave Tolnai
7 years, 6 months ago
If you publish my SIN next, I'm going to be a tiny bit freaked out.
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fartymarty
4 years, 5 months ago
@Dave - I'm just making one of these at the moment (self isolation project). I found a schrader valve that screws directly into the gauge thread. It saved me drilling a hole and installing the valve. I'm just sorting a few fittings for exit hose to use the existing threads then it will be finished.
Also these things can take a massive amount of pressure (mine is rated to 250 bar). Did you ever think of filling it with a compressor and using it a an air tank? You would have to be careful with the delivery of the air into the tyre but would save pumping it up each time you needed to use it.
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Dave Tolnai
3 years, 10 months ago
Awesome! Ya, I was hoping to figure out a way to attach something right to the regulator or gauge. There's so many different types of fire extinguishers, I'm sure it's just a function of searching for the correct one.
I had planned on using a compressor to fill it. I might start to worry a bit about some of my homemade bits getting a bit stressed out if the pressure got too high. I generally hand pump mine to about 120 psi or so and that easily does a tire with room to spare. So it's no big deal for me to pump for 60 seconds each time I need to pop a bead.
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