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No more flat tires???

Picture of No more flat tires???
Go-kart, wagon, wheel barrow... anything with pneumatic tires can easily be made into run-flat or no-flat tires. I was making a push-car for my kids and one of my tires had a busted valve stem. I couldn't find the right size inner tube... So I got to thinking.

Can I use canned spray foam and make it a tubeless tire?

Here are some pictures and instructions on how I did it.
 
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Step 1: The tires...

This could technically work with any pneumatic tires. I have only done these wagon wheels. I am going to try a kids bicycle next.

Here is a picture of the tire that had the broken stem. I usually have this spray foam around.

I figured how much the foam would expand and not utilizing common sense or gloves (this stuff sticks to your skin like nothing else) I took the wheel apart and squirted the foam into the  mouth of the tire... turning the tire... squirting... turning... till I had filled about half of the tire. I know it takes about an hour to fully expand so I put the wheel back together, tightened up the bolts.

I came back the next day and gave the tire a squeeze. Squishy, hard in places... not good. I took the wheel apart and saw my issue. The foam didn't grow as much as I needed. I was going to put some more in to fill the voids... when I thought, "Stick the tube into the valve stem hole!" I put the rim back together and did just that.

I stuck the tube, that comes with the can of foam, into the valve stem hole and pushed the end around to the opposite side of the wheel (so the tube is in the tire as far as it can go) and started filling. Pulling tube out a little at a time till the foam came out of the hole. Stuck the tube into the hole and did the same thing on the other half of the tire.

Came back next day... tire had some foam hardened outside the valve hole and in a couple places around the bead (Part where tire and wheel meet) Easily broke that extra stuff off with some pliers. *(foam comes off the metal really easy, not so much for the tire... or your fingers)

sdorguss6 months ago
I worked at a tire shop that does this for industrial tires. It is just that, foam fill. However the stuff we used made the tires VERY heavy. Quite common for skidsteer tires when they're doing demo work. Never thought of doing this with insulating foam tho.
alcalina8 months ago
Is it possible to use this tricky for bicycles?
bigtreehouse (author) 11 months ago
Update:
This didn't work. There formed a flat spot and they weren't round any more. Also when you put a load on the wheels for any amount of time the foam inside would break down and turn to dust.
cmartin-111 months ago
Where is the update? It has been 2 years. I am interested in hearing how it went.
You can buy solid polyurethane wheelbarrow and hand truck tires, through online vendors and some hardware stores (home depot and ag stores often have them, but charge an awful lot). They sometimes also have pre-made wheel-and-tire combos with foam filling already done (semi pneumatic).
For tubeless low speed pneumatic tires, I've had good luck just putting a pint or 2 of latex caulk mixed with windex into the tires and sealing them with it. It forms a layer in the tire and also will have some liquid "rubber" in there for a very long time.
Most large tire dealers have access to fill tires with a balck foam that doesn't break down. It is used in off road equipment that works in puncture prone areas, like building sites where numerous nails end up on the ground.
bigtreehouse (author)  alaskanbychoice1 year ago
Really? I have never heard of this.
I will look into this... sounds really cool.

Thanks
Any updates on how well this held up?
bigtreehouse (author)  cougarmandan2 years ago
Okay... after a time... with the wheel just sitting the foam broke down and made a flat spot. So this didn't work. Might with different foam...
bigtreehouse (author)  cougarmandan2 years ago
So far so good. Just checked them the other day. Don't use them as much as I thought... thinking of doing my hand truck.
olmon2 years ago
CaseyCase is right about this not being a good idea for the long run. I tried this about 12 years ago on a wheelbarrow tire. It was only good for a couple days of work before the foam broke down & the whole works had to be replaced then. It might last longer on something that doesn't carry much weight & isn't used too much, but don't try it on your car-- --LOL
Here's another project for insulating foam. I want to do this soon, but once you open a can, you have to use it, or so I'm told. Do you have any experience in letting a can sit open, then going back to use it in a few days?
traitor5613 years ago
cool man tell me how the bike tires work out thanks :)
bigtreehouse (author) 3 years ago
I figured... but I still wanted to try. It's only gotta work for 50lbs. of kids once or twice a week...
CaseyCase3 years ago
Dude, if this worked for you... rock on! But...

I'm very skeptical that this will work. I imagine that the foam has to off-gas in order to fully dry--the relative, air-tightness of the inside the tire would cause curing issues. Also, if it were able to cure, this type of foam would be susceptible to being permanently compressed within the tire with use and would most likely further lose it's integrity and break up into chunks, dust and wee bitty pieces.

I understand that spraying foam in tires CAN be done but it is done at a tire dealer with a completely different product and it can be not so nicey pricey.
Kiteman3 years ago
Oh, empirical science in action!
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