Stop the Tire Presses

Feb 22, 2022

Okay, it's time for the new puzzler. I'm going to describe to you a scene.

It's a gas station.

The scene is very simple. There's a customer there who's asking the young attendant to repair a tire. Not repair, but replace a tire. He has a bad tire which he would like removed from the rim and he wants to buy a new tire.

He has been asked by the customer to replace this tire. And he has it on the tire machine and he is about to break the bead, that separates the tire from the rim. At that very instant, the owner of the shop runs over and says, "Don't do it!" What did he see that caused him to run over, and stop everything, I mean, pull the plug on the machine? What did he see that made him stop the attendant from repairing this tire?

Here's a hint. He saw something in the trunk of the car that alerted him.



Remember the puzzler? The question was: What did the shop owner see in the trunk of the car? James Hoffa?

No, no, no. Okay. What he saw was a can of this flat tire fixer stuff. This stuff contains some chemical whose name I don't remember.

Propane isobutane or something like that. I don't know.

But it has the interesting property that it makes rubber expand. So if you have a flat tire and you pump this stuff into the tire, it actually attacks the rubber and closes up the hole.

But it is also extremely explosive when combined with several ingredients like oxygen, which is present in the air that's in the tire or in the air around you.

The other one is spark ignition. And some of the companies have changed the chemical that they use, they have some that are not explosive.

But if you were to just take this (and this has happened to real people I mean, unfortunately) if you were to take it and break the bead and cause a spark, it is very possible you could ignite this stuff and cause an explosion that would literally blow the tire apart and do things like blow limbs off.

So this is a didactic puzzler because if you happen to have used this stuff, make sure that you tell whoever is working on your tires that you did use it. Because there's a procedure you fill the tire with the air you let the air out you fill it with a let the airflow there and then you throw the whole thing away. You do this to obviously purge the tire of this explosive compound.

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