Newb question: why are there spikes on the keys?

[pillar]

Hi.

Just a dumb question from a newb:
Looking at this photo:

"Definitely the nicest lock Wal-Mart ever gave me"
indeed... indeed...

Brinks Shrouded, 6 pins, 5 spoorated top pins and 5 serrated bottom pins.

from
viewtopic.php?t=17879

Why do keys have these hills?
The pin is like an arrow there is only one height for the shear line.
Looking at the first pin going to the second pin. Between is a spike on the key. Why is this there, it is not needed as the tip of the pin matters.

[mhole]

It's there because cutting two v-Shaped valleys for the pins, results in a v-shaped peak between them. Sure, you could remove this, but it's an extra operation which has no benefits to functionality, so it stays.

Simple as.

[allan501]

The cutter is shaped with a flat bottom and sloped sides. Sort of \_/ shaped.

The teeth do help align a worn key. Without them you could insert a key to far or not far enough and the pins would rest against the slope instead of the bottom of the cut.

Also if you have a "stairway" key the key could be removed with the cylinder partly turned, ie 45 degrees. I don't know if stairway is the proper term but where each cut is lower than the previous, such as 13579, you could pull the key out at any point but with the teeth you have to partially lift the pins to insert or remove the key.

[Wizer]

The actual cuts for pins don´t wear as much when they are in a valley. The peaks protect the cuts.

[Raymond]

Forcing the pins to ride over the peaks guarantees a more scrambled effect as the key is withdrawn. But it can also provide a picking effect as it is wiggled in and out of the keyway while light turning pressure is applied. This is often effective on master keyed locks. Many code cutters can shift to a no-peak mode often referred to as 'laser cut.'

The keys are cut this way because thats the way it has been done for many years. The cutting wheels are usually "V" shaped so the make the ramps automatically. The old cutting wheels when operated by hand must create the ramps fore and aft to assist the pins to ride up and down when moving from one cut to another. Otherwise the key maker must take a file and make the ramps or smooth off the peaks by hand. Failing to do this will cause the key to be very rough moving in or out.

It is a fact that there will be less wear on the pins if the peaks are removed. As long as the key is inserted flush to the shoulder, the spacing will be correct. The key does not have to set in the valley to work unless you are dealing with a high security key system like Medeco.