I have a DPDT switch that is On-Off-On and I want to use it as a On-On-On (3 position selection switch). I've had a few ideas on how to wire it but I think there might be an easier way than my idea of using a NOR gate to turn the middle off to an on which I still don't think it would work like I want it to.

So how would I go about wiring this? I know I should use a proper selection switch but I don't have one and would like to use what I have at the moment.

 

The only way I can think of to do what you want is to use relay logic. By interlocking the relay contacts between themselves, LEFT ON picks up relay #1 whose contacts would disable relays #2 and #3. RIGHT ON would pick up relay #2 whose contacts would disable relays #1 and #3. The CENTER OFF position would insure that relays #1 and #2 were both off and their NC contacts in series would pick up relay #3. Relay contacts would then be tied to the loads. You should start by sketching out a Ladder Logic diagram to check it out.

 

sounds OK if you have the right DC available for the NOR gate, assuming the result only has to be logic level i.e. you're not actually switching some signal or a power level with lots of mA