Keyswitch Adapter - Sinclair C5 3D Printing

While recently cleaning up a C5 which had the old Keyswitch assembly I decided to try to make an adapter that would allow the use of any battery with the original Keyswitch. Currently the only way to use the Keyswitch asembly is to use a type 038 battery plus some pole adapters.

This is fine if you have a type 038 battery but for most owners, larger car batteries and leisure batteries are the ideal power source for a C5. So, with the help of the 3D printer we've knocked up an adapter that lets you connect the Keyswitch assembly. The connection to the battery is achieved using cheap quick release clamps.

The Keyswitch adapter design

Here it is printed out and connected up. I have added a strap that runs through the adapter and around the battery to hold it in place:

The Keyswitch adapter printed out

All connected up

Here is the original C5 charger, charging up a 62ah car battery.

Using the original charger

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