Did I take off the aquadag?

Sectorseven

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Hello,

I was using a dry paint brush to wipe off the back of my Sanyo EZ and I wasn't sure if some of the aquadag came off. I've read that the Sanyo's comes off real easy. Here's some pics, please tell me what you think.



 
I don't think so... I believe the reason people say it comes off easily is because unlike most, it's water soluble/washable. If you used a dry brush, I wouldn't worry about it.

DogP
 
Looks fine to me.
Those two areas you pictured usually don't have any on it. (around the anode area and yoke area)
 

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I just googled it and I'm pretty sure I've removed from at least one of my monitors (that would explain an incident I had). So I'm wondering. There are people on here that talk about hosing off their tubes. Wouldn't that do it also???

Guess I'll quit using Windex and paper towels.....
 
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So you're telling me paint thinner and Scotch-Brite pads on the rear of the tube are a no no? J/K, but I do use simple green and old paintbrush. Never heard of this coating before. What happens if it comes off?
 
I just googled it and I'm pretty sure I've removed from at least one of my monitors (that would explain an incident I had). So I'm wondering. There are people on here that talk about hosing off their tubes. Wouldn't that do it also???

Guess I'll quit using Windex and paper towels.....

The aquadag on most monitors doesn't wash off w/ water, but on these monitors it apparently does.

DogP
 
Aquadag

I'd like to know what aquadag is and what it is used for and what happens if it is wiped off. Thanks.

http://en.wikipedia.org/wiki/Aquadag

Aquadag
From Wikipedia, the free encyclopedia
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Aquadag is a trade name for a graphite based coating commonly found in cathode ray tubes. It is manufactured by Acheson Industries, a subsidiary of ICI.

The coating can be on the inside of the tube, where it helps to maintain a constant electrical field near the screen. Tubes intended for television use normally have an aluminised interior which acts as a reflector on the back of the screen, and forms one plate of a capacitor. Aquadag is also painted on part of the outside of many tubes. The glass, tube, internal aluminium coating and the outer Aquadag then form a capacitor used to filter the high voltage EHT supply.

Normally there are sprung contacts that touch the Aquadag. If this contact is missing or loose, arcing is often observed at times.

When removing a CRT from a TV set, it is wise to discharge this built-in capacitance to avoid a shock hazard when handling the tube.

Aquadag is a water based colloidal graphite suspension, and may be painted on to items to avoid build up of static, or provide electrical screening.

Aside from its use in the production of CRTs, Aquadag is used in many types of high voltage lab apparatus where the creation of a highly predictable electrostatic field is required. The surfaces of some metals (most notably aluminum) can develop nonconductive oxide layers which tend to disrupt the electrostatic field produced around the surface of the metal when used as an electrode. Aquadag is not subject to such effects, and provides a completely uniform equipotential surface for electrostatics.
 
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