repair banham lock

[opps]

Hi all

From time to time I come across Banhams where the "mortice" fails to stay in the lock housing when you pull the lever/handle on exiting the house. To leave the house you have pull the handle and push the mortice in at the same time to make it stay in the lock housing.





Are they serviceable?

 

[JohnD]

Never tried a Banham, but I expect there is a peg that is supposed to engage with a tooth to hold back the bolt, or something similar.

It is just a rim nightlatch body, so I expect you can take it off the door and remove the plate. Take plenty of photographs as you work as small parts may spring out.

Probably it's either old grease that has stiffened and jammed a moving part, or a broken or dislodged spring.

You can remove dirt and grease with white spirit and a small paintbrush.

You are not supposed to oil locks as it hold dust and grit, but you can lube the parts with a dry PTFE or molybdenum spray, or graphite powder.

The feeler under the bolt should release the bolt to spring out when the door is closed, so must be connected to the catch (as the bolt itself does not have an angled tongue)

I have a Chubb 4L67 I can look in, it might be a similar design.

 

[opps]

Thanks, I just happen to have some Trend PTFE spray on site.