door lock replacement

If this is an 'euro' cylinder, you need a key to extract the cylinder. This is used to turn the barrel about 30 degrees to rotate the operating cam and allow the cylinder to be slid out. If you don't have this to hand, you need to drill right through the cylinder which will destroy the pins and springs and allow you to turn the barrel to withdraw the cylinder. Drill through the 'narrow' part, not the bit where the key would go. About a 4mm drill should do it.

Hope this helps,

There's one screw which goes through the middle of the barrel, which is the only one you have to take out. However, if you haven't got the key, this probably won't work as the spigot will probably prevent the barrel being withdrawn. There's a tool to break the barrel in half when this happens, but you'll have to take it to a locksmith or arrange a home visit.

With the door open. Looking at the edge where the bolt pops out, remove the screws from above and below the bolt.

Take it to a locksmith.

A friend of mine had exactly the same situation and tried to drill it out. It took him many many hours to drill, and in the process he ruined the bolt mechanism as well as the cylinder. Given that the replacement came to around £100 for new bolt and cylinder a locksmith will open it in the cheapest manner possible. A locksmiths charge to pick it open then remove cylinder will be a lot less than a new lock if you get it wrong.

If you can, take the entire door into their shop, as you then avoid their callout charge (and the lockie can work on it in the comfort of his own shop, with tea etc)

replacement

OTOH if you drill in where the key goes in you cant really go wrong, and the replacement lock wil be closer to 20.

NT