Replacement of 55yr old brass lock from Mum's bureau

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beech1948

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I was asked ( yeh right we know how that goes) to get my Mum's bureau open after we emptied her bungalow. She's gone in a home.

The old lock was trashed and jammed with a bit of old pot metal key. Took 3 hrs to get it out.

Lock is brass, a full mortice type and is 3 inches wide, and inch and 3/8th deep and 7/16th thick. backset is 13/16ths.

Has anyone got an idea of where to look for an approximation of this old lock....ior even how to rebuild it as it is connected with brass rivets. Thanks in advance.
 
jdeacon,

Thanks for that link. I have already done a search of the UK suppliers and Smiths came up.

It seems that the UK sellers are all selling the same thing except for http://www.paxtonhardware.com/product/full-mortise-furniture-locks/furnitue-locks and possibly http://www.hafele.co.uk/shop/images/External/pages/137-47.pdf.

Hafele are the closest to the backset measurement being only 1 mm out on backset and I can fudge the rest of the fitting.

Paxton are similar but are 2.5mm out on backset.

So I'm still looking.

What I really wanted was to find some sites for real old time/ old fashioned suppliers who did not appear on the first 3 pages of Google and might be known to the folks here.
 
Setch,

I took it to a friend who builds clocks, watches and locks from scratch and we identified that most of the simplistic internals were mangled and parts were missing so I think that route is out.

Very good idea though so I will go back to Cheshire to my mum's and see if I can find the bits where they fell out upon extraction.
 
If you are looking for a replacement lock you could try these people http://www.martin.co.uk/products/locks-and-keys/locks

When looking for a replacement lock the only critical measurement is the distance to the pin, this must be spot on or the key will not locate through the escutcheon. It is often easier to have a slightly larger body on the lock if you can't get an exact match because you can cut it in, if you have a smaller body it will need patching and polishing in. The best solution would be to repair the original lock.

If you get stuck, you can send me the lock and I will see if I can repair it or match it from my box of antique locks.
 
Eric the Viking,

Thanks for the message. I had a look at Meadows and Passmore but as you mentioned the locks are too small. I'm surprised in a way that there are so few UK suppliers and that they all sell the same small choice of lock and sizes. The closest I've found is a "universal mortice lock" but it is still 1.5 mm off on the distance from the selvedge to the pin and so I'm a bit wary still.

The range of prices is enormous as well going from £6 to £34 and as far as I can see they are much the same locks. I'll keep looking but am also going to see if I can find one in the USA web sites or if I can find a 1/2 mortice one to fit and then cut out the mortice on the inside to fit. I had very much hoped not to have to do that.

I think I have been doing restorations for too long you can get too purist about these things.
 
re. brassware suppliers it might be of interest that Martins charge an astronomical price for their products. Go to HE Savill in Scarborough and you can buy same stuff for much much less...
 
The critical issue is the distance from the top of the front plate of the lock, called the selvedge, to the center of the pin which locates into the barrel of the key, a sort of mini M&T arrangement. So just finding any old lock will not work it needs to be within 0.5mm of the original measurement. That is the escutcheon for the keyhole will be wrongly positioned vs the key pin in the lock if this exact (+or- 0.5mm) measurement to the centre of the pin or escutcheon is not met.

I've only found 1 lock which might fit because of that issue. That's from a shop in Pregnana, Italy and they do not understand the request for measurements -- which every lock produced has usually -- and don't understand English. It's a bit like a comedy show from both of us willing to communicate but finding it physically difficult but at least they are trying. A friend working in Rome is trying to talk to them

I'm currently trying to assess if the selvedge will be long enough to bridge the existing mortice in the bureau sloping top and provide a place to screw into the frame. If not then is it smaller by some amount and will have to have some small additions of new wood to support the lock sides and the top or selvedge.

Distance from the top of the selvedge to the center of the pin is called the backset and can be either L/H or R/H depending upon the placement of the hinges for the panel. This is the critical measurement and is 21mm in my case. The current industry production standard seems to be 11mm, 15mm or 19mm. Ughh!! Finding the correct backset has been quite a problem.

The old lock has a top plate/selvedge of 80mm, a depth of 34.5 mm and a width of 49mm and a backset of 21mm R/H.

The search goes on as the Italian lock seems to be made of gold given its price of 79 Euros +VAT+P&p.
 
Lock fore-ends/selvedges are often too rough to show, so a thin decorative face plate with the same overall and bolt hole dimensions is often placed over the fore-end. When there are problems with the backset it is sometimes possible to use a thicker face plate, two face plates, no face plate (although on a door that often means that normal screw heads don't hold the lockcase in the mortice), or, rarely as modern face plates are already flimsy, a thinner one.

If one of your candidates was correct in all bar a too short backset, maybe playing with a face plate, or even turning the fore-end of the original lock into a face plate might get you closer.
 
John,

Many thanks for that idea it was something I had not yet thought of. I'm looking for someone who might be able to repair the old lock as I know nothing about locks so if you know of anyone please let me know. I'm trying to collect all of the three bits which fell out of the old lock when it was removed to assist in this.
 
The main problem, if it were me, with repairing the old lock is the rivets. If the old case had been screwed together, I was going to suggest borrowing the guts from cheap cabinet locks, like the A&E Squire ones for example, and making the old lock work again.

I'm assuming it's a lever lock. Most cabinet locks are. In fact you've said there's a pin for a pipe key, so it probably is. The most important part to still have working in the old lock is the bolt lathe. The bolt lathe has the bolt at one end, a stump usually in the middle, a talon and some way of constraining it to ride in one axis only. The talon has a V shape and is what the key blade sits in; and when the key is turned its rotation is translated into lateral movement of the bolt lathe via the talon. There is normally a little bump somewhere on the bolt lathe that rides in a slot in the case - the lanket slot. The stump passes through the gates of the levers (2, 3 or 4 levers are usual in a cabinet lock).

The levers are sprung and pivot on the lever post. They will have their gates at different heights and the true key through its bitting (the "crenellations" of the blade) will raise each lever such that the gates all line up with the stump at the point where, via the talon, the key is trying to move the bolt lathe.

There's an animation on the Lever Tumbler Lock wikipedia page. It doesn't show the lever springs or the lanket slot (which would be behind the bolt lathe anyway. And your lock has a pin where the rear keyway is.

You'd probably find that the lever pivot post diameter wouldn't match. And you'd have to be lucky, or very ingenious, to get the lathe travel and the gate and the stump dimensions matching.
 
beech1948":3qn1knmn said:
The critical issue is the distance from the top of the front plate of the lock, called the selvedge, to the center of the pin which locates into the barrel of the key, a sort of mini M&T arrangement. So just finding any old lock will not work it needs to be within 0.5mm of the original measurement. That is the escutcheon for the keyhole will be wrongly positioned vs the key pin in the lock if this exact (+or- 0.5mm) measurement to the centre of the pin or escutcheon is not met.

I've only found 1 lock which might fit because of that issue. That's from a shop in Pregnana, Italy and they do not understand the request for measurements -- which every lock produced has usually -- and don't understand English. It's a bit like a comedy show from both of us willing to communicate but finding it physically difficult but at least they are trying. A friend working in Rome is trying to talk to them

I'm currently trying to assess if the selvedge will be long enough to bridge the existing mortice in the bureau sloping top and provide a place to screw into the frame. If not then is it smaller by some amount and will have to have some small additions of new wood to support the lock sides and the top or selvedge.

Distance from the top of the selvedge to the center of the pin is called the backset and can be either L/H or R/H depending upon the placement of the hinges for the panel. This is the critical measurement and is 21mm in my case. The current industry production standard seems to be 11mm, 15mm or 19mm. Ughh!! Finding the correct backset has been quite a problem.

The old lock has a top plate/selvedge of 80mm, a depth of 34.5 mm and a width of 49mm and a backset of 21mm R/H.

The search goes on as the Italian lock seems to be made of gold given its price of 79 Euros +VAT+P&p.


I have a lock that is 21mm from centre of key to top of the face where the bolt comes out.
76mm wide. 51mm high. 14mm deep.
AF&S secure 4 lever No key though.

If interested PM your address.

Bod
 
Bod,

First many thanks for your offer even if beer tokens are to be exchanged. Your lock seems to be quite thick at 14mm as mine is only 9mm. The concern is expanding the mortice to 14mm in an 18mm thick panel. That would leave two sides only marginally thicker than veneer and with little strength.

You live in Fleet which is just a hop, skip and jump from Crowthorne. May I keep your offer in mind for a week or so as I sort through the other options please.

Again, many thanks in advance for your generosity.
 
Of course.

Bod
Ps mine could be cut down to 11mm thick, but is a rebate surface mount, rather than a true mortise lock.
 
If you are looking for a replacement lock you could try these people http://www.martin.co.uk/products/locks-and-keys/locks

When looking for a replacement lock the only critical measurement is the distance to the pin, this must be spot on or the key will not locate through the escutcheon. It is often easier to have a slightly larger body on the lock if you can't get an exact match because you can cut it in, if you have a smaller body it will need patching and polishing in. The best solution would be to repair the original lock.

If you get stuck, you can send me the lock and I will see if I can repair it or match it from my box of antique
 
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