Security Pin Questions

[TheCrow]

I have been reading all the post on security pins and how to repin, and looked at several pictures of the pins themselves. My question is this:
In the top pins, either spool pins or serrated, will the cuts in them catch on the shear line? Obviously the cuts in the bottom pins will catch, but I'm a little confused as to why they would cut the top pins.
Any help is apreciated
TheCrow

[linty]

when there is nothing in the keyway to push up on the bottom pins, the top pins actually sit partially below the shear line.

[Gordon Airporte]

when there is nothing in the keyway to push up on the bottom pins, the top pins actually sit partially below the shear line.

Yes, this is how locks lock. The spring pressure pushes the stacks down (or up for Euro cylinders) so the driver pins cross the shear line.
If the key pins were so long that they protruded above the shear line you wouldn't even be able to assemble the lock, and there'd be no way to open it if you did. Lifting the pins like a key or a pick does wouldn't be able to help.

[lunchb0x]

the serations on the bottom pins wont catch because the serations are to small, if you have all security pins in the top they could catch but would depend on the type of pins you use

[TheCrow]

Ok, so if the top pins' serrations won't catch whats the point in putting them there? Thanks for the replies, they help me to understand a little better.

[lunchb0x]

sorry, for some reason i thought you ment when the key is being used, and it wwas late when i wrote that

when picking the pins would be binding in the cylinder, the groves on the serated pins will catch on the shear line, if you lift the pin to high it would be the serrations on te bottom pin, then to unset the pin with the security pin you will need to back uf the tension and when doing this, depending on the picking order a couple of pins might fall down.
I like to pick with a small and solid tension tool, with this you only need a little tension but I can feel hat is going on n the lock alot better, also after you work out the picking order it will make it easier to pick the security pins.

sorry is i confused you