removing knobs from heater control etc

[suzi6]

Trying to replace switch plinth on 74 tr6. Not having any luck
removing the knobs. Is there a secret in doing this without
destroying them. Any help will be appreciated.
Paul Jones

 

[hondo402000]

on the rod that the knob fits on is a spring loaded pin, so on the underside of the knob is a hole, you have to push a small nail up in the hole on the knob to push the pin in and that will free the knob to come off, the pins usually get rusty and difficult to push in so WD40 them when you get the knob off

hope this helps

 

[mgNOT]

Paul,
After all these years, some of the knobs have developed a strong attachment to their position. I have had success with a penetrating agent with a flexible straw-like spray attachment. PB Blaster,or a silicone spray. Be sure to depress the bullet that is usually on the underside with a not too pointed object before trying to remove the knob. I must admit to using a prybar behind one of my knobs. The risk there is ruining the part it is attached to, which if it were a wiper switch would be a bad deal. Good luck.
-Dennis

 

[suzi6]

I did notice the hole on them and sprayed with pb. I will try the pins asap
thanks

 

[TR3driver]

If you do decide prying is necessary, I'd suggest using some small strips of wood to protect the plinth, and using a pair of pry bars, one on each side, so the net force is directly outward. Using a single pry bar doesn't pull straight, which increases the chances of something breaking. Of course you'll use the 4th hand to keep the pin depressed

What I found was that the plastic knobs had shrunk with time, until they were a very tight fit on the shaft. Used an X-acto knife to trim them just a bit inside, until the fit wasn't quite so tight.

Somewhere, I've read an article about modifying a small C-clamp to apply force to the pin, but I don't recall where offhand.