# Locksmiths: key teeth up or down? **URL:** \ **Category:** Factual Questions\ **Created:** [March 18, 2004, 11:49pm UTC](https://boards.straightdope.com/t/locksmiths-key-teeth-up-or-down/235113 "2004-03-18T23:49:41Z")\ **Posts on this page:** 6\ **Page:** 2
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [October 8, 2017, 1:57am UTC](https://boards.straightdope.com/t/locksmiths-key-teeth-up-or-down/235113/21 "2017-10-08T01:57:03Z")
> [@rsacker](#): > > The deadbolt has upward facing teeth and the entry lock has downward, both Schlage. Is there ant literature on how to reverse this? Take it apart and look at it. This stuff isn’t rocket science. Seriously; it oughta be obvious whether you can turn that particular model of lock over. But it will depend on the particular model number which you haven’t given us. > [@bob\_2](#): > > Most door locks I come across these days don’t have ‘teeth’ at all. They have grooved on a flat blade. We have five front door keys in the safe and none have teeth. The safe has buttons. That’s certainly common on cars here, but substantially all US doorlocks, even new ones, are still old-fashioned toothed keys. > [@Kedikat](#): > > I have a related question. > The button to lock a door knob. I think that it should be that when it is locked, the rib on the button should be horizontal. But it does not seem to be universal. I have this fanciful notion that the orientation of that rib is meant to represent a barred or unbarred door, in miniature. Is there any substance to my notion? Tha’tcertainly the way most of them work. Which I agree has that meaning. But the other guys always build their stuff different just to be different. ---
**Author:** ![Rosvirein](https://avatars.discourse-cdn.com/v4/letter/r/e0b2c6/32.png) [@Rosvirein](https://boards.straightdope.com/u/Rosvirein)\ **Post date:** [October 8, 2017, 1:34pm UTC](https://boards.straightdope.com/t/locksmiths-key-teeth-up-or-down/235113/22 "2017-10-08T13:34:57Z")
> [@Kedikat](#): > > I have a related question. > The button to lock a door knob. I think that it should be that when it is locked, the rib on the button should be horizontal. But it does not seem to be universal. I have this fanciful notion that the orientation of that rib is meant to represent a barred or unbarred door, in miniature. Is there any substance to my notion? All the ones I’ve ever worked on can be assembled whichever way you prefer. I did a new knob on my front door a couple of years ago vertical=locked, because that’s the way the contractor who put in the door years ago did it, and that’s what I was used to, so I did the new one the same. ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [October 8, 2017, 2:01pm UTC](https://boards.straightdope.com/t/locksmiths-key-teeth-up-or-down/235113/23 "2017-10-08T14:01:58Z")
@rsacker > [@LSLGuy](#): > > Take it apart and look at it. This stuff isn’t rocket science. > > Seriously; it oughta be obvious whether you can turn that particular model of lock over. This is true in about 80% of locks but not with Schlage. Some of their locks could be tricky for a layperson. Although in my experience with them, they are reversible. There must be a YouTube video, right? Like other brave souls I’ll buck the pros and say practically speaking it doesn’t matter which way the teeth are oriented. I’ve changed hundreds and hundreds of locks and deadbolts, many up to 30 years old, and I’ve yet to find one that has failed due to dirt build up on “upside-down” locks. ---
**Author:** ![FluffyBob](https://avatars.discourse-cdn.com/v4/letter/f/ecb155/32.png) [@FluffyBob](https://boards.straightdope.com/u/FluffyBob)\ **Post date:** [October 8, 2017, 6:53pm UTC](https://boards.straightdope.com/t/locksmiths-key-teeth-up-or-down/235113/24 "2017-10-08T18:53:14Z")
Convention is that the tumblers in a cylinder face down, such that the flat part of the key and key way are down. People expect this without thinking and try to insert the key with the teeth up, following convention avoids unnecessary fumbling. Door handles are usually ‘handed’ left or right. Symmetric handles like knobs usually are ambi, while levers may need to be ‘rehanded’ to the right orientation. Most modern lever sets have removable handles that make that easy, but some may need to be purchased in specific handedness. Keyed entries (handles with a lock), if not re-handed properly can result in an upside down keyway. They usually have removable handles for this purpose but sometimes the mechanism requires something more involved. Weiser keyed entries (and I think maybe Kwikset) for example require a special tool for re-handing. Deadbolt latches often have a proper vertical orientation usually marked with an arrow, and if not installed properly can result in an upside down keyway. Lock cylinders are not symetric because of the tumblers, which are usually in a fin on the top of the cylinder. Because of this the keyway on a deadbolt bezel will usually be offset to the bottom of its face with a Logo printed above. An upside down deadbolt will usually have an upside down logo which should be pretty obvious. ---
**Author:** ![LadyT1a](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ladyt1a/32/8889_2.png) [@LadyT1a](https://boards.straightdope.com/u/LadyT1a)\ **Post date:** [September 10, 2021, 7:37pm UTC](https://boards.straightdope.com/t/locksmiths-key-teeth-up-or-down/235113/25 "2021-09-10T19:37:29Z")
\*\*got a copy of a key for my boyfriend n he told me it didn’t work. Well, as I’m looking at the key after him stating the teeth were wrong n that was why: I noticed that the grooves that go in verses the other side where it pops out……they put the teeth on the wrong side. He says it don’t matter n I don’t know what I talking about.m ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [September 10, 2021, 7:50pm UTC](https://boards.straightdope.com/t/locksmiths-key-teeth-up-or-down/235113/26 "2021-09-10T19:50:45Z")
Wow, we used to have a lot of locksmiths here. [Previous page](https://boards.straightdope.com/t/locksmiths-key-teeth-up-or-down/235113.md?page=1)