Posted by Ian McColl on December 04, 2000 at 09:40:20:
In Reply to: Question for Ian and the other Locksmiths out there: When can a handcuff be repaired? posted by J. Lauher on December 04, 2000 at 08:46:08:
Dear Joe: Many factors come into play when one considers a repair to a handcuff.
Firstly a key is needed to make sure the mechanism is working correctly. This is not a matter of just making a key to the handcuff, the key needs to be made as if it was to the dimension of the original keys supplied to the cuff. Then the key can be tried and if it fails to work there maybe a problem with the cuff.
The darby handcuff is a classic, as the key screwed onto the locking bolt and then off the bolt, the first few threads of the bolt get twice as much wear than at the other end, so if a key is made to the correct thread pitch for that cuff, it still may not pick up the thread when it is first screwed into the cuff. The rarity of the cuff would have to be considered and new bolts could be made if warranted.
The construction or how the cuff was originally assembled is another factor. Tower handcuffs have a cast body and a steel plate "cap" which is set into the casting. In the cast lockcase, a raised section encircles the inner space for the mechanism. Once the bolt, levers and pawl are in place the cap was inserted and the raised edging hammered over. This raised area was then ground off and the cuff either polished or plated.
The cap is about 1/8 inch thick ( thicker in the leg iron ) and any attempt to remove it will cause damage beyond expectation. As the raise section has already served it's purpose and been removed, there is nothing to use to restore the cuff to it's normal self. ( However the most common problem I attend to is the missing 'drill pin' or key post which can be made and replaced)
Cuffs made of stamped steel parts such as most swing through handcuffs can be worked on. These are usually riveted together ( with either the rivets ground flush or left raised) In both cases the rivets can be punched out and new rivets made and then replaced.
Some cuffs like the Judd and Maltby have about 20 pieces making up the inner workings and some of these are very small. A cracked lock case is more likely to be the problem and/or broken springs.
The cuff is not viable for repairs.
Another that could be said looks the same as the above is the Mattatuck and although it shows signs of being held together with rivets, these are in fact machine screws with the heads ground off.
An unplated cuff is far easier to restore than a plated cuff as to effect repairs the plating will be damaged and the cuff usually needs to be replated. ( Nickel plating is still available as all chrome plating has to be done on top off nickel, so the cuff can be plated and removed after the first step)
If anyone has any other questions as to the repair of handcuffs please email me direct or post a message here.
:I receive lots of email asking me about missing keys and
: the repair of nonoperating handcuffs. As a service
: to the readers of this forum, could you outline some
: of your experiences?
: How does one judge if a handcuff can be repaired?
: thanks
: Joe