Well Woody, you know the routine, TAKE LOT O’ PICTURES! I’ve done a few early AD door latch mechanisms, a bunch of light switches and been into quite a few vintage radio components, i.e., volume controls, etc. If your very careful and only bend the tabs just enough to get the unit apart you should be ok. I would pay special attention to bending anywhere there is rust because this presents a stress riser and you might snap a tab off there.
I can’t say for sure but I would be willing to bet that the core valve that the vendors require, would have to be in pretty decent shape for them to credit you with it.
Like I said, I haven’t been into mine yet but it looks pretty basic. Well Cleon whoever is the first one to jump in the water, make sure and let the rest of us know how hot it is!
Of course the capillary tube sensor is the same principal as the temp gauge Bill. But I’m just not sure whether these are filled with a gas/liquid or just air. It would seem that since the motor in this case is a diaphragm with a rather large area that air expansion would be enough. In the case of the temp gauges the motor is only a Bourdon tube with a small area so there isn’t much lever age. For that you need the pressure of liquid to gas conversion to power it.
And no, I never did get the original temp gauge restored, I ran into a brick wall when it came to the calibration. The volume of Ether is very critical to the calibration and it would take more experimentation than I can afford time wise and monetarily to establish a standard. When I was a kid you could buy Ether in a bottle from a lot of local sources, like the Walgreen’s or Rexall drug store. We used it for snuffing bugs for science projects. Now days I found it about impossible to get it and actually never did find a supplier. So the only source was to buy a donor temp gauge for a source, that gets expensive.
On the Ranco valve sensor that Woody has pictured, it looks like there is a very small bulb at the end, which might lead one to think that there is indeed, some kind of liquid inside. I’m sure that the guys that are rebuilding them for the vendors aren’t gonna let you know if they are filled or not, that would take the bread off their plate.
Metal diaphragm barometers are usually just filled with an inert gas like Nitrogen or Argon and just plain air in the cheap ones.
Denny Graham
Sandwich, IL
Last edited by Denny Graham; 07/17/2008 2:05 PM.
