A restrictive lock and key mod.

[Altashot]

A fun, quick and easy mod.
It doesn't really make a lock more secure but it may restrict key duplication. It makes it harder to duplicate, to some degree and It may also make it harder to pick, or
at least confuse the picker. It can be done to almost any pin tumbler cylinders and is good to fool "key cutters" at the mall or hardware store.
Even a locksmith would be wondering why you have a key modded like that...I certainly would ask questions before i cut it.
There isn't really any good use for them, but I've made them for people that are really concerned about bumping. It does effectively prevent
bumping with conventional bump keys... As long as the bumper is unaware of the device...

Have a look.

http://s1155.photobucket.com/user/Altashot/story/82917

M.

[flywheel]

Good stuff as always!
Why did you choose that spot? Just so it remains concealed? I imagine you could move it to the middle and make picking even tougher while remaining an effective bump stop. Even if the picker knows it's there getting leverage without oversetting the near pins would be tough. Do that in addition to a plug with restrictive keyway also would be evil.

[GWiens2001]

I like it. Simple yet effective.

Have done something similar before by drilling a hole in about the same place and installing a brass rod as a rivet, then filing it flush with the plug. Then filed a groove in the tip of the key, leaving the key forked. Like your modification, the key would have any lockie wondering what the heck was going on. These days, as you stated, the key kiosks would likely start throwing sparks as it tried to process the key. Maybe I'll mod a key in both ways and see if the kiosk at Lowe's will copy them.

Gordon

[GWiens2001]

Good stuff as always!
Why did you choose that spot? Just so it remains concealed? I imagine you could move it to the middle and make picking even tougher while remaining an effective bump stop. Even if the picker knows it's there getting leverage without oversetting the near pins would be tough. Do that in addition to a plug with restrictive keyway also would be evil.

Think if it is moved too far up the keyway, the part of the key extending beyond it would be too likely to bend.

Gordon

[Altashot]

I chose that spot to not weaken the key too, too much.
Had I done it, let's say, between the 2nd and 3rd pin, I would have had to file so much off the bottom of the key that it would become extremely weak.
And yes, you could make a very evil cylinder, especially if all the key cuts were shallow, you could make the plug cut deeper and insert a taller key block...

M.

[Oldfast]

I like it. Not too difficult to do. Very simple. Very effective.

Likely to spoil the vast majority of any bumping attempts.
Could also see it really throwing me for a loop when picking!

[flywheel]

True true.
The bump stop could be much shallower and minimalize the mod that weakens the key.

[s1deshowmick]

Excellent, I really like this mod.

[flywheel]

I've seen my mail key a thousand times but today is the first time I actually looked at it. The partial missing tip made me think of this thread. I'm guessing the USPS uses locks with a built in bump stop.

2016-01-25 13.04.48.jpg

2016-01-25 13.05.55.jpg

[Malekal]

Nice idea! I like it!

[Altashot]

No, it's not a bump stop, although it does work as one, the key blank also has the cut out.
These keys shoulder stop, the cut out is to clear the "C" clip at the end of the plug.
It allows the lock to be shorter while keeping a 5 pins config.

M.