Circuit conversion - newbie needs help...

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Guys
I have a faulty wired remote control for a remote camera mount. It is a simple 4 way joypad (pressing on rubber dome switches on the board underneath).
It also has a variable speed control, a simple sliding resistor also on the board.
It is connected to the camera mount via a 7 pin din connector at the end of a meter of cable.
I have had this remote fail several times now and therefore decided to make a more robust version myself. So I bought a 4 way joystick (the type with 4 simple on/off switches - I don't need or use diagonal control). I mirrored EXACTLY the circuit from the old remote, taking care to carry the common connection through all the switches in parallel and use the 'normally open' position on it switch, but I cannot get it to work.
I have walked through it a million times as it is so simple, but cannot see anything wrong.
The only thing I can see different is that when the old remote 'closed' the circuit with the rubber dome switch on to the board, my meter shows a very slight resistance, but on my new circuit there is no resistance at all, it's a clean flow.
Am I stupid to assume that I could replace rubber dome switches on circuit tracks for simple throw switches, or is the logic ok?
Any help please. I can photo what I have if it helps.
Cheers
Martin

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I have tried really hard to draw a diagram of the before and after, I realise it is not to recognised standards, but I have done it as a layman

I hope this helps a bit.

[pebe]

The fact that you have zero resistance across the switches should make no difference to its operation. You have checked the switches, but have you checked that the common terminal is wired to its correct pin?

If that is OK, I would suspect the wrong resistor value.

[JMACgyver]

Martin,

Pretty decent sketch, better than I usually manage.

1st question:
Looks like you have seven wires leading off each circuit. On the original, are ALL the DIN pins used?

2nd Q:
Recheck your DIN pin assignments. Youd be surprised how easy it is to reverse a connection when translating connections from male to female or solder-cup side to pin-side

3rd:
Make sure your variable resistor is of the correct value. If it's off, you may just be experiencing a 'slower-than-a-dead-tortoise' effect. Personally, I prefer rotary pots due to the noise slider one can create.

I have modified many switch boards, and haven't found not matching the keypad contact resistance to be an issue with them. Your sketch seems spot-on; I would also recommend breadboarding it temporarily with discrete switches rather than the joystick, and you can troubleshoot from there. Only other thoughts I have are to do a continuity check throughout the devices.

Regards,
DYM

PS: If you PM me the specs, I might be able to build one for you at parts cost.