Are bottom pins different shapes?

[beardyweirdy]

What I mean is, I have been studying the bitting on this ABUS cylinder lock key, at it appears to be that some, if not all, of the bottom pins are pointed where they meet the key.

Is this likely? Possible? Definite? Not likely?

[SnowyBoy]

Well the have to have a slight chamfer on them otherwise the wedge on the tip of the key couldn't get under them to lift up.

[globallockytoo]

In a pin tumbler system each bottom pin is bullet shaped (tapered and pointed) to enable the pin to sit correctly in each cut and to allow the cuts to pass easily past the pins. If they were not pointed, how would you get the key in or out?

Diameter of pins varies between manufacturers, but essentially they are all the similar shape.

[beardyweirdy]

Well the have to have a slight chamfer on them otherwise the wedge on the tip of the key couldn't get under them to lift up.

Yes, I see that more clearly now.

On examining another key, from another maker, the areas where the pins sit are more flat than pointed down into a V shape. Of course, I have only ever studied these two keys, and they happen to appear to be quite different, I was trying to imagine what the pins must look like where they engage the key.

Thanks all.

[yng_pick]

Most locks have the pointed bottom pins, a major exception being Kwikset, which have flats. The cuts in a Kwikset key are also wider to mate up well with them.

Generally there will not be a mix of pointed in flat, unless someone has mixed universal pins in with originals say on a Kwikset.

[nostromo]

Check out various MEDECO bottom pins if you can get'em. At first I thought they were all one chisel shape but after getting some disassembled locks, discovered that the blade of the chisel can be off center. And when the side groove comes into play there are several combinations. One of these days I'll get one of those MEDECODERs.

Sounds like you're having fun, weirdy beardy! Good on you!!!

[Evan]

Check out various MEDECO bottom pins if you can get'em. At first I thought they were all one chisel shape but after getting some disassembled locks, discovered that the blade of the chisel can be off center. And when the side groove comes into play there are several combinations. One of these days I'll get one of those MEDECODERs.

Sounds like you're having fun, weirdy beardy! Good on you!!!

@nostromo:

You are discussing the differences between fore pins, aft pins and original pins... This was a new development for the biaxial locks made by Medeco some 25 years ago...

~~ Evan

[Evan]

The shape of the bottom pins depends on the lock in question...

In general, bottom pins are cylindrical in shape with a bulleted/chamfered end which contacts the key and a flattened end which is in contact with the upper pins in the pin stack... While the diameter of the pins is all standardized at .115" for most applications, it is the rounded end of the pin which drives the requirement for using a cutter wheel with a different bevel angle and cutting width which will shape the slopes between bittings on the keys cut as well as how wide the area in each cut where the pins seat on the key will be...

Some notable exceptions are the flattened pins used by Kwikset and Wiser lock...

High security locks sometimes use chisel point pins with an angle like Medeco and Corbin-Russwin's inactive Emhart lock technology...

BEST access systems makes security bottom pin segments which are spooled on the sides in addition to having the rounded bottom to interface with the key...

~~ Evan

[Rickthepick]

Dom have some awkward bottom pins and almost impossible to get a pick under them properly

heres a good pic someone posted on here

[cedrice]

it really depends on the manufacturer of the pins. Original weiser, schlage, sargent etc all look different. Same goes for lab pins. Some are more pointed (Schlage) and some are flatter on the bottom (Weiser).