Flyback glue/sealer

Stephen

BetterBit
Staff member
Founder
Sep 5, 2021
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Did you accidentaly do some filming about the procedure? It looks amazing!
Could you please just explan what exactly you did?
I would like to know "how" did you clean, what are the tricky point at refilling...

I am not an expert of flyback transformers requirements.
How did you clean it? Only physical cleaning or chemical as well? How did you removed the "deeper" pieces...?
What are the main requirements what in case of a resealing need to take in consideration? Electrical isolation, air insulation, visual covering...
Basically a visual inspection — if I could see yellow glue I scraped it away. If I recall correctly, I used a plastic spudger for most of it and a flat head screwdriver for uncooperative spots. No chemical baths, just prepping the surface with 99% IPA.

edit: It's worth noting, applying the RTV Silicone neatly was challenging. I think somewhat recall using the windex trick to keep it from sticking to my finger. I packed it into the top to ensure there was a solid seal.
 
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reallyrandy

Tinkerer
Oct 30, 2021
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New Jersey
After perusing Youtube, I found some videos (mostly in Bengali). Even though they're not in English I got the gist of it.
In one video here, RTV silicone is used on the anode cap. This is what @Stephen used on his flyback. RTV is widely used in the auto industry for a gasket sealant due to its heat resistance. Although I think I'm gonna go with dialectric grease, or maybe the deadly red stuff.

Another video says you can use solder flux (dunno 'bout that).

This video uses something called Araldite epoxy for the flyback sealant, found here.

I'm (maybe stupidly) assuming the flyback sealant can be anything as long as it's heat stable and non-conductive. Maybe that RTV silicone would be a good choice. Epoxy seems too permanent for my taste.

What's the consensus on this? Any opinions?
 
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JDW

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Sep 2, 2021
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After perusing Youtube, I found some videos (mostly in Bengali). Even though they're not in English I got the gist of it.
In one video here, RTV silicone is used on the anode cap. This is what @Stephen used on his flyback. RTV is widely used in the auto industry for a gasket sealant due to its heat resistance. Although I think I'm gonna go with dialectric grease, or maybe the deadly red stuff.

Another video says you can use solder flux (dunno 'bout that).

This video uses something called Araldite epoxy for the flyback sealant, found here.

I'm (maybe stupidly) assuming the flyback sealant can be anything as long as it's heat stable and non-conductive. Maybe that RTV silicone would be a good choice. Epoxy seems too permanent for my taste.

What's the consensus on this? Any opinions?
Technically speaking, you could even spread Silicone Grease under the cap to accomplish the same. You can seal leaks in the flyback with silicone grease too. It's just that with grease, it will attract dust and grime.
 

polpo

New Tinkerer
Oct 30, 2021
14
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3
Super Corona Dope is one possible replacement solution, but it is expensive, rather deadly according to the label, and high gloss versus the matte finish of the original red substance that was under the cap originally.
I thought Corona Dope was for resealing flyback transformers. It cures hard so wouldn't be good for the anode cap.
 

JDW

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I thought Corona Dope was for resealing flyback transformers. It cures hard so wouldn't be good for the anode cap.
The red substance under the anode cap that is applied directly to the CRT is not glossy, but it is "hard" (i.e., not soft or rubbery to the touch). Even so, I've not found a replacement that perfectly matches the original red stuff.
 
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