Blocking a keyhole

[Andy008]

What would be the best substance and method to use for blocking a keyhole of a lock, rendering it useless?

(Don't worry this is for securtiy reasons, not criminal damage, it's my own lock)

[ICEMANSAV]

epoxy resin, from a builders merchants, goes in like a paste from a tube and sets hard as rock

[andyjevs]

Super glue does a good job too

[snapdarlich]

You can get superglue out. We had a wee joker block one of the locks in our shops, but several applications of nail varnish remover got it working again. Took over 2 hours though!

[qapmoc]

Somewhere I have seen a lock for a lock, it is a small gadget which goes into the keyhole and blocks it, it is then locked into place with its own small key. The only thing is I can't remember where I saw it ! You know, after you looked in X number of shops and catalogs they all sort of blend together in your mind, well at least they do in mine.

[derekpara]

As ICEMANSAV says, Epoxy resin, like Araldite will do the trick.

[BillyBB]

As qapmoc stated, it's called a lock block and is made by Burg. A good locksmith will be able to get hold of one. This is for lever mortice locks common in the UK. Take your key with you to ensure that it would be suitable for your lock. Even quicker, call a locksmith to change the lock!

[SteveD]

How about leaving the key in the lock and partly turned(on the inside of course!).

[espookid]

Why not just cut off the front of the key and push it in , it can always be removed by taking the lock out of the door of course this only works with the "Yale " type locks

[gary baldy]

Having trying to clean up after a toddler i recommend Weetabix- sets rock solid.

[BillyBB]

SteveD, never leave the correct key inside a mortice lock, many burglars have ways of turning them.