Just to get you going you could link out the button or if it is a modular type then removing the switch block from the actuator should restore the circuit. Keys for estops are usually a standard number for each manufacturer but can Often be supplied with a customer specified key. As Michael says the number on the lock should get you a new key either from a locksmith or online. If you don’t need a key reset then consider replacing the actuator with a non locking version, latching with twist release or non latching are usually available.

Mike

Depends on how you weigh the balance between non-destructive methods and speed of the solution! Self-tapping screw and a slide hammer?

Assuming it's a pin tumbler lock like this:

they can be picked by applying a gentle constant undo turning force to the cylinder with the blade of a small screwdriver. The blade doesn't enter the lock, it engages just enough to maintain turning pressure on the cylinder. Then a needle is used to joggle the first pin until its gap (purple and tan in the picture) aligns with the cylinder and lets it turn enough nip the pin in the unlocked position. Then do the next pin in the same way.

Although simple the technique takes a certain amount of practice and patience. Not too difficult on a cheaply made lock with only 4 or 5 pins, much harder to pick a Yale door lock or an expensive padlock. As the lock on an emergency stop button will be cheap and basic, there's a good chance it can be picked.

Professional locksmiths have a tool for undoing tumbler locks. Works in the same way except the pins are vibrated mechanically, effectively deskilling the job. No idea how successful they are; my guess is they work well on cheap locks, and struggle with well-made ones. Worth trying before breaking the lock.

Can you approach the problem from the other side? Although the switch has a lock on it, it's unlikely the box has! May be possible to open the box from the back and take the switch off, in the worst case replacing it with a modern one.

I suppose the lock is to stop workers restarting a faulty machine. Long history of railwaymen causing major damage by shunting engines under repair despite large red 'DO NOT MOVE' signs!

Dave

Edited By SillyOldDuffer on 02/09/2020 09:35:29

If the switch is a Klockner Mueller/Telemecanique it could be key serial number SF101, double sided commonly available at most locksmiths/key cutting shops.

Emgee

If it's fs fp locker type key anything that is similar has a good chance of doing it. I have the same problem occasionally in my job so I carry 3 odd keys and that does the trick 9 times out of 10. Old Austin, Morris etc car keys are the same.

It's actually worth trying anything that will fit in the lock without force then give it a gentle tweek. When trying other similar keys rake the key in and out with a bit of welly between trial turns of the key, give it several goes before moving on .

It's a cheap simple lock, usually easy to pick. You need a tension wrench to provide light torque while giving the pins a jiggle about, the stainless steel strip found in car windscreen wipers makes good tension wrenches though a screwdriver or similar can be pressed into service, lockpicks are typically made from steel shimstock, 25thou to 15thou being a workable range, a single triangle toothed shape to "rake" back and forth would most likely get you into this one.

Loads of videos on youtube, try a search for the lockpickinglawyer for some quality inspiration.

I have picked similar desk drawer locks using paperclips, though I wouldn't recommed that as it is fairly tricky due to the lack of tool strength.

Edited By Cabinet Enforcer on 02/09/2020 12:56:03

And Thanks, Jon, for letting us know the outcome. Not everybody remembers to do that.

George B.