Air conditioning vacuum control switch

[Keith Fry]

Does anyone have such a thing?
It is the dash mounted switch with a transparent green operating knob - the usual Rover P6 dash knob - which controls the engine vacuum destination. In other words the engine vacuum is diverted to the vacuum motors in the heater cooler unit to open/close flaps to control air destination and temperature. The maze like configuration in the photo is the rubber surface attached to a steel plate which connects the various holes in an alloy distribution plate. The rubber on my switch has perished (it is almost 50 years old and rubber has a shelf life of 10!!) and leaks vacuum, so the flaps in the heater cooler unit are not moved. I guess it is pretty unlikely that I will find one in working order since many of them are likely to have perished rubber if they exist, but it is worth a try. I am also investigating having the rubber control surface remanufactured using 3D printing techniques which is a whole new ball game. If anyone has any interest/ability in 3D printing it would be great to hear from you.

 

[So Cal V8]

No promises Keith, but I just might have what you're looking for. I will take a look tomorrow when the whiskey has worn off.

You may want to have a chat with Steven (sdibbers) of this parish as he may be able to help on the 3D printing front - I don't want to make promises for him, but that may be right up his alley, and he's a decent fella, so drop him a line.

Alan

 

[sdibbers]

And as if by magic......

Hi Keith, Good to meet you! The part doesn't look too bad to recreate. Good news/bad news time for you a bit here. The bad news is that 3D printing technology isn't quiet there for rubber parts as yet. The good news is that it's very easy to make a 3D printed tool to cast a new part in silicon rubber if you gave the correct geometry as a reference. You can mould the silicon part and use an appropriate adhesive to attach to the metal plate. You can use polyurethane elastomers to directly mould to the metal plate but initial investment is higher and might not be worth it.

In fact I've started a company doing just that for high end classics about 3 months ago. (Mods please feel free to tell me off for linking here and I will remove if need be)

You can see the website here: Additive Restoration - Store
Our facebook page is here: Additive Restoration - where technology meets artisan car parts | Facebook
Feel free to contact with a PM.

Best,

Steven

 

[Keith Fry]

Many thanks Alan and Steven. Hope springs eternal and it is the new year.