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Old 09-18-12, 11:41 PM   #1
Saving Hawaii
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Bike Theft Mythbusters

tl;dr: I've heard it said that a lock can be defeated using a typical road flare to cause lock failure. I tried that today on a rather weak lock and it failed, so rest easy.

I decided to try that today when a roommate's cable lock stopped working permanently locking his bike to our porch. We can't get a pair of bolt cutters so hopefully this thing isn't stolen overnight. Nice bike in a bad neighborhood.

My attempt to defeat the lock with a flare failed. There was substantial deformation of the cable but it did not fail with simple and direct heat application over a period of 10 minutes. Subsequent mechanical attempts with wire cutters and "forceful pulling" also failed.

The flare I used was not actually a typical road flare. It was a backfiring fusee. Very similar to a road flare but designed for lighting fires. This device burned hotter and faster than a regular road flare would have.
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Old 09-19-12, 10:00 AM   #2
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try this: get a can of comp. air (comp. duster), hold upsidedown and unload the can on a lock, see if it'll shatter. Saw it on Burn Notice and have been wanting to try it.
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Old 09-19-12, 10:57 AM   #3
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try this: get a can of comp. air (comp. duster), hold upsidedown and unload the can on a lock, see if it'll shatter. Saw it on Burn Notice and have been wanting to try it.
"Burn Notice" isn't exactly a wealth of truthful information. And no, the can of compressed air will not be cold enough to shatter any lock.
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Old 09-19-12, 11:56 AM   #4
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And no, the can of compressed air will not be cold enough to shatter any lock.
Not entirely accurate.

Firstly, it is not "compressed air" that is stored inside the can, but rather some liquid gas with boiling point of approximately -50 deg. C. The procedure is performed with inverted can, which makes the liquid gas to get ejected from the can in liquid form and then evaporate on the surface of the lock. Given enough cans, this will indeed cool the lock to the boiling temperature of the liquid gas, i.e. approximately -50 deg. C.

Secondly, the question is whether this temperature is sufficient to compromise the strength of the lock. It depends on the lock. The shackle of even the cheapest locks is usually made from steel that won't become brittle at -50 deg. C. However, the body of the lock and, sometimes, load-bearing parts of the locking mechanism are sometimes made from materials that do indeed become very brittle at that temperature. There quite a few videos on the Net of the locks whose bodies easily split in half after being cooled with liquid gas from "compressed air" can.

Although, to be fair, it is quite possible that such locks would shatter relatively easily without any additional cooling.
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Old 09-19-12, 12:28 PM   #5
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Hammer and a cold chisel.
Impact hammer.
A/C refrigerant, aka Freon.
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Old 09-19-12, 01:21 PM   #6
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what kind of lock mechanism? padlock? combo?
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Old 09-20-12, 10:41 AM   #7
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"Burn Notice" isn't exactly a wealth of truthful information. And no, the can of compressed air will not be cold enough to shatter any lock.
Have you ever shot your wife in the ass with an upsidedown can of compress air? Yeah, you'd remember if you did............................

It'll form ice crystals after a few second burst, so I can imagine how cold an entire can would be and I could very well see a lock break afterwards with a good smack of a hammer.
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Old 09-20-12, 11:08 AM   #8
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http://www.youtube.com/watch?v=9j4DqevlIRY
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Old 09-20-12, 12:24 PM   #9
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Have you ever shot your wife in the ass with an upsidedown can of compress air? Yeah, you'd remember if you did............................

It'll form ice crystals after a few second burst, so I can imagine how cold an entire can would be and I could very well see a lock break afterwards with a good smack of a hammer.
What happens after you smack your wife on her frozen posterior after giving her this foreplay? Inquiring minds want to know.
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Old 09-20-12, 12:39 PM   #10
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What happens after you smack your wife on her frozen posterior after giving her this foreplay? Inquiring minds want to know.
re-read the part "Yeah, you'd remember if you did............................"..........does that explain enough? I didn't think the cold would travel through denim, but it suuuure did!
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Old 09-20-12, 12:46 PM   #11
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It'll form ice crystals after a few second burst, so I can imagine how cold an entire can would be and I could very well see a lock break afterwards with a good smack of a hammer.
As already said, it'll get down to about -50 degrees C -- but no colder, even if you use more cans.

The question is ... is the can even needed? You can typically break these locks with a hammer without freezing the lock, so it's not even clear that freezing the lock helps.
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Old 09-20-12, 01:11 PM   #12
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Have you ever shot your wife in the ass with an upsidedown can of compress air? Yeah, you'd remember if you did............................
No, but I did something to your mother once and SHE never forgot THAT!


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It'll form ice crystals after a few second burst, so I can imagine how cold an entire can would be and I could very well see a lock break afterwards with a good smack of a hammer.


If imagination is all you have, you still have nothing. Ice crystal forming on a surface of a material is not evidence of material degradation. Stop thinking that everything you see on TV is real. Your presumptions are very indicative of someone with an IQ below sea level. Try again
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Old 09-20-12, 09:55 PM   #13
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re-read the part "Yeah, you'd remember if you did............................"..........does that explain enough? I didn't think the cold would travel through denim, but it suuuure did!
But I didn't do it, so I don't remember what your wife's response was; perhaps you can fill me in, then I promise to remember.
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Old 09-20-12, 10:09 PM   #14
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Pretty sure she'd say the noodle was not aldente.
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