What Keeps The Lower Pins From "Falling Out"?

[danreller]

OK, This may be a Duh question, but, I've always said if you need to ask it it's not a stupid question. What keeps the Lower pins in the plug? Why don't they just fall out due to gravity and jiggling due to picking or general vibrations (doors wafting due to air currents or a dog jumping up against it)? Are they made to much closer tolerances than the upper pins in the cylinder and just stay in because of their light weightedness and friction? I can envision the upper pins needing to be "loose" to increase the success rate of the lock. But, what's the story on the lower pins?

[Chucklz]

They usually rest against one of the wards of the keyway. And barring that, well the bottom of the cylinder will keep them in. This is another one of those cases where you shouldn't take our word for it, go out and open up a lock and see for yourself.

[danreller]

Thanks Chucklz. I think you've answered my question. There must be a taper to the hole that holds the lower pins in. What's the correct term for the cylinder or channel that the pin resides in?

[Chucklz]

I've always called it a chamber. Interesting bit about 'smithing is that it is indeed at least a thousand years old, so the terminology isn't standardized per se.

[marso]

It is nice to see the first interesting question in days. (I have only had time to skim really) Thanks for the post, it got me thinking and yes the chamber keeps it from going forward and the wards keep it form falling down.

[CitySpider]

I have seen an extremely cheap lock where the pins were kept from falling out because they rested on the bottom of the keyway. You could see the break between the top and bottom pins (the first one, anyway) just by looking at it -- basically a straight rectangular keyway.

I can't imagine that the lock would last a comparatively long time. Shoving the key against pins that low has to do some damage.

[CitySpider]

Now that I reread what I just wrote, there must have been something holding them in from front to back. I'll have to try and take a closer look at it, next time I'm in that part of the building. I'll let you guys know.

[joecool2727]

It is nice to see the first interesting question in days. (I have only had time to skim really) Thanks for the post, it got me thinking and yes the chamber keeps it from going forward and the wards keep it form falling down.

ok i was thinking about it also i thought this too. but then i remembered that i have seen many locks where you can see the space between the two pins which means the bottom pin is not actually in the chamber. am i right on this? what is keeping the pin in if it isnt in the chamber?

[Chucklz]

Same stuff as before. Wards etc.