The client has learning difficulties and does not recognise numbers. He has been given an allotment near his home as he is a very keen gardener. The allotment has a keypad lock however which he cannot operate. It is necessary to first press C for clear. The client can do this. A five digit code has then to be punched in to open the gate, which he cannot manage. If all five numbers are pressed together, the gate will open.
To establish that the design basis of setting all keys simultaneously would not be deleterious to the lock, Borglocks.com was contacted – the lock is a BL3130 model (23/11/2015 at 1550) – who confirmed that the practice would not cause damage to the lock mechanism, provided the tool was removed prior to operating the lock.
The modified design therefore incorporates a recess shaped to hold the lock operator knob in the neutral position whilst the keys are depressed, and the knob can only be operated once the tool has been removed.
The design comprises 2 principle components, the code plate with 5 M4 x 11.5mm screws cut to length and smoothed to prevent damage and a cover/locator plate retained by a further 4 M4 x 8mm screws.
The code plate was fabricated from ¼” aluminium plate, cut to shape, and drilled an tapped with 13 holes to align with all buttons on the lock, with a cut-out over the C key position, and a recess shaped to fit the top half of the lock operator knob. Finished item was painted and positions identified to correspond with the lock, to facilitate easy re-coding.
The cover plate was fabricated from a piece of plastic coated tin plate steel, bent to cover the code plate and conceal the code pins, and facilitate alignment of the pins with the code buttons. Finally a holster was made from canvas to enable the tool to be carried on the client’s belt.