C2200 LED kit

[c_dk]

Local client purchased ACs LED kit for the C2200. Brought it to me for installation and found this discoloration under the meter blue filters.

The bulbs overheated the meter case and discolored them. Mike at AC says replace the meters but someday they will be all gone. Any ideas how to "polish" away the discoloration. I think of removing the glaze on automotive headlights as a possible example.

I will install the new LEDs and supplied filters to see how yellow the meters are.

 

[kevzep]

Ah yes polycarbonate headlight lenses/covers, I use cutting compound on those, but for these you might need something with a more delicate action like silver or brass cleaner, something with a slightly abrasive action but not too aggressive.

The best part about LED's is the lower operating temp...

 

[c_dk]

If your meters are starting to look like this.....after LED kit the discoloration is still there.

Now I have to take it back apart to find a solution.

 

[kevzep]

Should have used the cutting compound....:scratch2:

 

[c_dk]

I now have the meters out on the bench. Tomarrow I will try to get the discoloration out with a fine abrasive.

Today I had to put the finishing touches on a pair of rebuilt W5Ms.

 

[kevzep]

I now have the meters out on the bench. Tomarrow I will try to get the discoloration out with a fine abrasive.

Today I had to put the finishing touches on a pair of rebuilt W5Ms.

Hopefully it hasn't penetrated through and its just on the surface.

 

[c_dk]

Replacements are $100.00 US each. I will most likely take the meter itself apart to see how deep the discoloration goes.

 

[c_dk]

The discoloration is in the almost vinyl like meter face back. Going after it with a 150 to 1500 grit wet sanding progression.

 

[c_dk]

I know there is a little brown left but as your sand off the vinyl?? you thin it which lets more light through. This seems to be a good compromise.

How the heat got thru the injection molded clear meter case to overheat the face back stumps me.....

When talking to parts yesterday Brian volunteered that these meters are used on many units.......could this be a common issue coming up for all metered preamps?

Maybe the title should be changed to McIntosh preamp meters showing discoloration.