Zenith Halo Cataract Removal, How I Did

[ctc17]

First, let me stress safety. Cover yourself and ware a face shield.

This is a mod on Dougs How to repair CRT cataracts RCA removal how to. Watch these videos first. http://www.youtube.com/user/drh4683#p/u/78/5l1EoMmmOcQ

The Zenith style is a soft glue, almost like wet silicone.


This is the Zenith style crt with green halo.


First remove the tape.


Pile of removed tape.


Just as in the video, I warmed the lens up a bit to soften the glue.


This is what Im using as a hot wire to cut though the glue. I got a 5 pack of these guitar strings for $6.


You could use an old filament transformer for this. Something fairly high current. Im not sure what this transformer is out of but the secondary output is about 10volts at 20 amps. Im using my variac to regulate the output so the guitar string doesnt just turn red and burn.


Size the guitar string up to be just about an inch longer than the small width of the crt face. Screw it down to to blocks of wood wrapping the string around the screws. It has to be fastened to the wood well.


Turn the vairac up to where the wire gets good and hot but not to the point it weakens. This takes some experimenting. Start at the corner working through the glue.


Work your way through....


Keep going....pulling back and forth a little....


Getting there. This really went very fast. Less than a minute to cut the safety lens loose.


Lift lens off.

From here follow the cleaning and re installation steps in Dougs (drh4683) Videos.

This was much easier than I thought. When the lens and wire are warm the wire cuts right through the glue with ease.

[newhallone]

Hot wire! Good idea. this is a great post thanks!

[DaveWM]

nice work. I assume a petro based solvent? let me know what you use.

[ctc17]

Not sure what its made of. You can just kinda roll it off with you fingers. Its almost like jello.
It smells nasty, this is an outside project for sure.

[sanjarali]

This is amazing! On pieces of glass!!! And how they think always You do something like this?

[Dan Starnes]

I know a guy who did it that way. Thanks for posting this. That is very fast.

[drh4683]

Very nice! Looks like it worked great for you! Look forward to seeing the finished product.

[ctc17]

This was a junk crt I brought home form SC. All the guns are shorted and red is totally dead. I wanted to test this method out on a junk crt before destroying a good one.
That Zenith goo stinks bad! Acetone takes it right off.

I just finished removing the glass using your method off a junk rca roudie. Look at this! I couldnt even tell it was this bad before getting it apart.

[bgadow]

I'm gonna have to try this sometime. I was kinda scared of this method, dealing with that hot wire and all, but you made this look easy!

[freakaftr8]

Man that is awesome!! Kinda makes me want to perform this on my Heath Kit! That goo is really nasty!!

P.S sorry guys I was gone for a while, work sends me on some freak trips for a month every year (and no internet access).... Waaaahh

[1993ctc175]

this is Very Interesting!! Yes, I have seen cateracts on the so-called gel-coupled crt's. The gel or "the glue" whatever you called it. as it ages that how its happened when the sets are getting old. so, I WOULD be interested in seeing those cleaned-up crt's. I have seen a rebuilt crt with separated safety glass - Only one!! upon installiing onto the television set.

Cheers!!

[1993ctc175]

Caution - Do not bake the Color crt!!

OH, By The Way, when you guys are going to clean the cateracts of the Picture tube OR Rebuild a CRT. DO NOT BAKE THE CRT OR the Shadow mask inside of the color crt right behind the facescreen of crt will warp causing purity problems. I have watched the manufacturing process on youtube and THEY NEVER BAKE the CRT or the aperture mask will warp!!

[ctc17]

The professional rebuilders put the whole thing in an oven so Im not sure about that. Also not much heat makes it though to the crt face. That goo on either type of crt is a great insulation.

[AUdubon5425]

Originally Posted by ctc17

And now a word from Squibb, makers of Pep-O-Mint Life Savers...

[ChrisW6ATV]

Great pictures, ctc17. I also really appreciate Doug's videos (drh4683). I followed his techniques this past weekend on my first cataract surgery and it went exactly as he described, on an RCA 21FJP22A. I didn't have halogen lamps to do the preheating, but I am in California, so I just let the CRT sit face up in the sun for a couple of hours first!