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Originally Posted by bob91343

Gads don't do that! All plastic parts will suffer. That includes dials, rubber feet, dial cords, windows, pointers, and many electronic components.

Ummm, no, they won't.

My posting specifically referred to only the chassis, but it seems that the rest of the case wouldn't suffer from baking.

You surely are aware that most components, such as caps, are typically rated up to temperatures higher than 135° Fahrenheit? Caps are usually good to 85° Celsius, which is 185° Fahrenheit. Carbon-film resistors are good up to 155° Celsius. One could conceive of using a heat gun upon only the ceramic caps, or doing it with NOS parts that had not yet been installed. So my comment wasn't totally outlandish, ignorant, or downright stupid as you made it out to be. I would not bake nitrocellulose, acetate or other low-softening point (or flammable!) plastics.

The fellows over at Antique Radios routinely bake radios at 180° Fahrenheit to remove moisture and improve performance:

I have done this many times even with complete radios. An hour in a pre-heated oven at 180 deg F. should be fine, even longer will not hurt.

A transformer that has been soaked in paraffin will have some dripping, one soaked in bees wax even less as bee wax has a higher melting point than paraffin. Transformers that have been vacuum impregnated in varnish should not experience any flow of the varnish.

Much above 200 deg. F will cause extrusion of pvc or rubber insulated wire, not good.

and furthermore:

I have a spare oven in the cellar workshop, connected across one leg of the 120 volt line, with a modified thermostat, which allows it to stay at between 160 and 180 degrees. I bake almost every chassis in this oven for several hours to fully dry it out after cleaning, and before I attempt electrical restoration. baking the RF cols in many early bettery sets makes for a tremendous improvemnet in performance, particularly in those sets with lorenz coile, or sets using fiber coil forms.

Given the above technical note this makes perfect sense. (As does driving out any residual moisture.)

The interesting part of the technical note, and why I posted it, beyond the explanation of aging, was this: "After the soldering process, the capacitors have essentially been De-Aged." That's interesting to me and it explains why the performance improves after baking.

Some repair shops would even soap up and hose down dirty chassis before working on them:

In the '60's I ran a TV repair shop and would often have a TV that was so filthy that the techs would not touch it. We'd take it into the alley behind the shop and shoot it down with liquid soap, and maybe bug killer (protecting the speaker of course) and then a through rinse with a garden hose. Next came the critical part - get this set dry ASAP. We used compressed air and a squirrel cage blower from an old furnace. It would seem to be dry in a half hour or so but we always ran the blower for a day on it. Never lost a set.

and

When washing chassis, I use only one tablespoon of dishwasher detergent (Electrasol), one tablespoon of Borax, and a teaspoon of Washing Soda. This does not corrode aluminum, but rather leaves it perfectly clean, and removes the yellow corrosion form Cadmium plating.

Baking the set in an oven for twelve or fourteen hours at 165 degrees does indeed get all remnants of moisture out of coils and transformers. I use a modified "Yard sale" built-in oven set up in my workshop., as the Better Half looks askance at the use of our kitchen appliances for this purpose.

So there!

And as far as baking electronics with plastics, a common trick to rejuvenate video tapes is baking them at 135-140° Fahrenheit for about two hours. The sibling site even has a page about doing this in a toaster oven. I knew a fellow who made a tidy sum, from audiophiles and business migrating tapes, by doing such baking before the technique was widely known.