Plastic Key. Defeat Magnets.

[totos]

Ok, how about this then.....


Brass everything as normal, little disc magnet set in the top of each top pin, another oposing magnet set in the stack cap.... no need for springs! Slight posibility it would be unbumpable then.

a little problem...
if there is no springs, you can push both pins above the shear line and the lock will open!

[FrenchKey]

unless the whole pin stack is too long.
it is not a problem.

[SnowyBoy]

Ok, how about this then.....


Brass everything as normal, little disc magnet set in the top of each top pin, another oposing magnet set in the stack cap.... no need for springs! Slight posibility it would be unbumpable then.

a little problem...
if there is no springs, you can push both pins above the shear line and the lock will open!

A spring compresses down to the same lengh as 4 magents (2 up 2 down).

It doesn't work well anyway, I neeed to get some 3mm ones and try.

[w00tb0t]

Although overly complex to be reliable; hydraulics and a very very small relief valve could prevent bumping by requiring a second or two before the pin could force enough fluid out of the chamber to rise to the shear point.

But then again there are a million other elegant ideas to prevent bumping, Im curious to see how the magnet idea went, I have some nasty neodymium magnets at home, I wonder if that Yale I just took apart pins are ferous...

[w00tb0t]

So, just as I thought, the Yale pins are just as ferrous as the rest of the brass pins in the world, regardless of its silvery appearance.

The Yale key I have for the lock is heavily magnetic though, which made for some hilarious results.

I used a generic 3.5 inch hard drive magnet.

[SnowyBoy]

So, just as I thought, the Yale pins are just as ferrous as the rest of the brass pins in the world, regardless of its silvery appearance.

The Yale key I have for the lock is heavily magnetic though, which made for some hilarious results.

I used a generic 3.5 inch hard drive magnet.

Nice...... I do like the hydraulics idea though. I'm just trying to think how to implement it.

[adamtwoz]

rare earth magnets demagnetise more every time you bump them. So having them in the actual pins getting whacked every time a key is inserted is probably not a great idea in the long run.

[w00tb0t]

Nice...... I do like the hydraulics idea though. I'm just trying to think how to implement it.

I think it would be near impossible to implement reliably in a lock, simple issues like leaks and blockages would render the lock useless and in some cases locked near permanently. There are a million other elegant ways to defeat bumping in general, ....such as not having pins

[SnowyBoy]

rare earth magnets demagnetise more every time you bump them. So having them in the actual pins getting whacked every time a key is inserted is probably not a great idea in the long run.

No they don't. They loose their magnatism if they are heated past certain temperatures.

[w00tb0t]

What is Curie Point!

http://en.wikipedia.org/wiki/Curie_temperature

[bluefish6900]

Yes magnetics would have issues but here it goes anyway.
Build the pin stack with magnetics of different lengths the same as with brass pins, but use an opposing magnetic at the top of the pin chamber (as a spring) to keep the pins at the bottom of the chamber. Not sure if this would make it difficult to get the key in or not but would be interesting to try. would have to play with the strength of the magnetics to get a balance. Or maybe it wouldn't work at all. Just an idea.

Bluefish

[totos]

Although overly complex to be reliable; hydraulics and a very very small relief valve could prevent bumping by requiring a second or two before the pin could force enough fluid out of the chamber to rise to the shear point.

then it'll require the same amount of time for the pin to get back. this means that if you want to open the lock, you have to (slowly) push the driver pins above the shear line, then let the key pins drop down freely and spin the cylinder. if you want the lock to be resistant to picking, you'll have to make the fluid flow back into the chamber faster than it flows out of it.

[SnowyBoy]

then it'll require the same amount of time for the pin to get back.

errr, again.... no.

You'd be pretty buggered if your car suspension returned at the rate it went down.

[FI2NH]

then it'll require the same amount of time for the pin to get back.

errr, again.... no.

You'd be pretty buggered if your car suspension returned at the rate it went down.

I believe that what totos said is true, depending of valve and even more of what is used to drive this hydraulic system.

Car suspension usually uses some sort of mechanical returning system, as coil springs etc.

However, if lock has it springs and hydraulic system as dampener, i see no problem, but it would not be very cost efficient.

[SnowyBoy]

then it'll require the same amount of time for the pin to get back.

errr, again.... no.

You'd be pretty buggered if your car suspension returned at the rate it went down.

I believe that what totos said is true, depending of valve and even more of what is used to drive this hydraulic system.

Car suspension usually uses some sort of mechanical returning system, as coil springs etc.

However, if lock has it springs and hydraulic system as dampener, i see no problem, but it would not be very cost efficient.

True, mechanical spring helps them return. But gas shocks return under their own pressure... they give gradual resistance on the in stroke, but return immediately on the out. If Totos theory was correct, it would mean the user would not be able to extract the key before the dampers were ready to return.