bathroom thumb lock

[raspberry]

Hi all.
First post here.
So, I have to fit a 'thumb turn lock' to the bathroom door.
The thumb turn lock comes with the knob and fittings, including the square steel shaft that operates the (seperately purchased)sprung catch. The steel shaft is about 5mm square.
The sprung catches that I have seen in the DIY chain stores all have square holes much bigger than 5mm.
Am I missing something here?
Search as I might, I can't see how a 5mm square shaft on the thumb turn lock is going to operate a sprung latch with a 8(?)mm square hole.
Packets were all sealed, so no parts missing.
Can any one please advise...something this simple is driving me nuts!
I'm a reasonably accomplished DIYer as well :-/.
Many thanks.

 

[London Mike 49]

The 5mm spindle is the British standard for bathroom locks, if you are trying to fit the thumbturn onto a standard deadbolt with a latch then the 8mm spindle is made for that type of lock.
Either change the lock case or compromise with some other arrangement.

Mike

 

[raspberry]

The 5mm spindle is the British standard for bathroom locks, if you are trying to fit the thumbturn onto a standard deadbolt with a latch then the 8mm spindle is made for that type of lock.
Either change the lock case or compromise with some other arrangement.

Mike

Thanks Mike.
The lock is new, screwfix, it's a circular thumb type and fits indpendently under the standard handle that is already fitted to the door (ie it's a stand alone unit) it's a new fitment , ie no holes in door frame yet. So, I need a new latch with a square hole to match the 5mm spindle...do they exist? I cant find one in the usual places and I can't be the only person to experience this problem. I'm quite capable of making a 'fix', but it does seem odd that I would have to do this.

 

[London Mike 49]

Most of the stuff that I buy like locks comes from ( amongst other suppliers) ironmongery direct and they are very helpful if you give them a call they will give you good advice about what to buy.
The bathroom lock type that are made for thumbturns are like the one where the 5mm spindle goes in the lower smaller hole in the lock.

Mike

 

[JohnD]

search for "bathroom sashlock" or "bathroom lock." Union and Imperial both make/made them but they are not often seen. Hotels use them.

I might have a couple of spare ones, 2 1/2" or 3", open to offers.

You seem to be using the word "lock" when you mean "latch" or "deadbolt" or "thumbturn"