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TR2/3/3A TR3 Dash Knob Question?

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CCURTISS

CCURTISS

Jedi Hopeful
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I have two dash knob questions.

The first photo is my RHEOSTAT SWITCH for my fan heater. The car has never had a knob since we have had it and I looked up the knob in the Moss catalog and there are two types of knobs. One is called a "retained by stud" and one is "retained by screw". I suspect mine is the "retained by screw", can someone confirm which I have by the picture below?

The second photo is my wiper switch and it is missing the spring clip that holds on the knob. Has anyone been able to find a way to fix this or do I need to buy a new switch?

CIMG0822.sized.jpg


CIMG0824.sized.jpg


Thanks!
 
That is the screw type heater control. Good luck finding a screw to fit, though !

Personally, I'd just replace the wiper switch. Good used ones are pretty cheap on eBay, if you don't want to spring for new. And I'm not fond of trying to machine parts under the microscope.

But to fix it, I'd find a piece of flat spring steel to cut to shape (like the broken spring from a carpenter's tape measure or perhaps an old feeler gauge); then anchor it with a tiny screw (like 2-56) and machine a "top hat" plunger with the brim of the hat too big to fit through the hole (assuming you've lost the original plunger).

Another approach that might be workable (if you don't mind it working differently than original) would be to thread the existing hole for a short hex socket setscrew (what the English call a grub screw) that screws in through the hole in the knob. I fabricated a vent pull for my TR3A that way many years ago, and it's worked quite well all this time ... As long as I remember to unscrew it to remove the knob !
 
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