Kaba Simplex 900 Explained

Here I take apart a Kaba Simplex 900 push-button lock and explain its inner workings.
If you're looking for something specific:
15:25 - How combinations work
26:57 - How double etc. presses work
41:03 - Bonus content: Half-presses

[@imyxh]

This has to be one of my favorite KZbin videos of all time. Thank you for the incredibly detailed and well-presented information! These locks are very, very cleverly designed.

[@TomNimitz]

Thanks for the video. I've always wondered what was going on inside these locks. They've always seemed to have an imprecise feel to me, but now that I see the internals, I can appreciate the innovative design. (I too found my way here after having been left hanging by the Lockpicking Lawyer's video.) Skip to 15:30 for the interesting stuff.

[@scottberry3866]

Just sayin', I obtained a Truck Vault security box with a Simplex 900 deadbolt as a lock. It was used, and the combination was unknown. I used your video to disassemble the lock, find out the combination and reset it. Thanks so much, your video saved me a $150 bucks at least!. Keep up the good work.

[@timfischer]

How does this not have any comments yet? Thanks for the DETAILED explanation. What a cool mechanical lock. Just came here from LockpickingLawyer's video on a similar lock, and a comment directed me here after commenting that I wondered how they worked. Most of their locks used vertical buttons, and it's clear that the mechanism was designed as such. They must have thought the circle was more appropriate for residential, or other more formal/less industrial uses?

[@morningstarmadworks2679]

Can't say I have a perfect answer for you. The form factor is different which might work better for certain doors. I've also seen them combined with a normal door knob so you can have multiple locks (figure a large group of people has the combo, but someone has the authority and ability to lock the knob). It also requires less equipment and effort to install in the door and frame. You only need to drill a hole for the button cylinder to pass through. Everything else is screwed into the door or wall. A typical door lock or deadbolt would require a more exact pattern, drilling the side of the door, and doing some carving with chisels.

[@SoWe1]

This was a very good video, I will get around to watching your other two as well. Why are you not making more videos? You are explaining it very well. What I didn't catch out of this is how the reset mechanism works and what exactly happens mechanically when you turn the knob. If that's in the other videos, I'll see it :) cheers

[@hectorv.648]

Help…My locking/unlocking knob keeps spinning and can’t unlock mine even after I put in the code

[@vbutler22]

My lock (unlocks and locks) with the turn of the nob without the need to input the combination. How do I fix this problem?

[@morningstarmadworks2679]

Seems like you've set the combination to be nothing. To change that, remove the screw at the top, clear the lock, press the button under the screw (you'll need something long and pointed, a pen might work), enter your new combination, and then turn the knob to open the lock.

[@washingtonwebfoot9908]

Warning! The bolt is very soft metal. This is typically the source of malfunctions with this lock.