Which switch do I need?

[Mr Spigot]

I am in the process of installing my new wiring loom from Autosparks. My car has flashing indicators front and back, but also has the original trafficators fitted (which have not been used for decades), which have been tested and (with a small amount of refurbishment) work. The new loom includes wiring to connect the trafficators in addition to the flashing indicators, but I wish to install a switch so I can turn them off and isolate them from the indicator switch circuit or turn them on if required. I know the trafficator circuit will have to bypass the flasher units so that I don't have trafficators trying to fly the car!
I have been looking at simple toggle switches, but cannot find any which can deal with two separate circuits (left and right) and either have them both on or both off. I have several old Lucas switches, but these seem to just transfer power from one side to the other, not having both sides either on, or off. I have gone round in circles trying to find DPST or DPDT switches which will do what I want, so would appreciate some help from those who know what they are talking about!

[simmitc]

You need a Double Pole Single Throw DPST switch. This is effectively two separate switches operated by a single lever. This will provide an on-off operation. When I did something similar, I used a 3-pole change-over relay so that it was either indicators fed from the flasher or trafficators fed from non-flashing supply.

[Mr Spigot]

Thank you. So, with my elementary knowledge of electrics, that will have 4 terminals for left in/out and right in/out and the connection between each pair will either be on or off?

[geoberni]

I am in the process of installing my new wiring loom from Autosparks. My car has flashing indicators front and back, but also has the original trafficators fitted (which have not been used for decades), which have been tested and (with a small amount of refurbishment) work. The new loom includes wiring to connect the trafficators in addition to the flashing indicators, but I wish to install a switch so I can turn them off and isolate them from the indicator switch circuit or turn them on if required.

I'm not familiar with how Autospark include wiring for both Indicators and Trafficators.
Given that for a car to have both, the Indicators are going to have been a retrofit at some point, it leaves many possibilities for the existing configuration...
If Autospark have made their own hybrid, where in the loom have they included the 2 different layouts?

What indicator switch have you got, a Stalk one, I presume....
Your problem is that Indicators are invariably designed to have a single Flasher Unit in line with and before the Selector Switch.
How big a redesign do you wish to undertake?
What configuration do you really want?

If you want both to operate from the Stalk, with Indicators always, but to have the Trafficators as selectable in addition, you're really going to have to have a separate flasher for each side.

[Mr Spigot]

The Autosparks loom has provided a separate flasher unit for each side for the indicators, operated from the indicator stalk. There are additional L and R indicator cables in the boot (to connect to trafficators) and corresponding L and R cables coming out of the loom behind the dash - separate to the indicator system. I intended to take the dash cables directly to the indicator stalk, but with the on/off switch mentioned above.

[geoberni]

The Autosparks loom has provided a separate flasher unit for each side for the indicators, operated from the indicator stalk. There are additional L and R indicator cables in the boot (to connect to trafficators) and corresponding L and R cables coming out of the loom behind the dash - separate to the indicator system. I intended to take the dash cables directly to the indicator stalk, but with the on/off switch mentioned above.

Sounds like you're all sorted then....

[Mr Spigot]

Hopefully sorted! Many thanks @simmitc and @geoberni for your clear advice.