|inside euro lock case|
These locks were oval profile mortice sash locks.
If you aren't familiar with this type of lock they usually work by throwing the bolt which is then locked into place by a single lever.
The problem this locksmith kept encountering involved the spring steel lever spring fracturing.
This causes the bolt of the lock to fall between open and closed if the key is turned to quickly.
When the user comes to unlock the door they find it wont work as the euro cam is trapped in the wrong part of the lock case by the intermittent bolt position.
So i put this question up on one of the locksmith forums i use and here's the fix that was recommended by one of the veteran locksmiths:
"replace the lever spring". LOL I never realised you could buy spare lever springs to make repairs like this and it is going to save a lot of hassle ordering a new lock case and of course the extra cost.
It is simply a case of inserting the new lever spring into the groove and peening over the metal to hold it tight.
Carefully bend the lever spring into position and try to get the majority of the bend in the first half inch so that it isn't too highly sprung at the other end which could cause it to jump out of position.
If the lock is beyond repair and a new case is required then try and order a superior model such as the Walsall ACE lockcase recommended to me by Walsall locksmiths. These incorporate a heavy duty machined piece to hold the bolts position as opposed the the lesser quality sprung lever as pictured above.
Thanks for reading my locksmith Blog
PSS locksmiths Sheffield