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Is there any danger associated with sawing the glass tube off the neck of a CRT picture tube? Answered

I had an idea to saw the glass tube projecting off the back of a CRT picture tube (the part that has the pins on the back and surrounds the electron guns) that I have lying around and put it in a plexiglass case or something cause it would look cool.  I need to know if there are any dangers in doing this that remain after the obvious things such as discharging the tube and breaking the seal on the back of the neck.  I do know that the screen is coated with a phosphor that is not good for you but this should not be an issue because i am not going to be working with the actual screen part right?



There is usually a tiny little nib on the back of the tube. Wear eye protection and a face shield, and nip the nib with a pair of pliers. The vacuum will be broken instantly, and you don't get an implosion.

The glass around the gun connector is pretty thick, just beneath, around the guns it generally isn't. Once you've released the vac, I'd crush the neck to release the guns, and then dress the edges with a diamond wheel.

If you don't see that nib immediately, look between the pins at the gun connector; it's sometimes located there.

Rumor says that this is a standard technique that TV repair shops used to "disarm" picture tubes before discarding them, back before they were reclassified as a Hazardous Material and most towns started charging a fee to dispose of them. Rumor has been known to be very wrong. I'd check with someone who does this for a living before assuming it's the right answer, though it does make a certain amount of logical sense.

After it has been vented, I tend to agree that my first step would be to try a glasscutter rather than a saw of any kind. I think there's an instructable on cutting glass; if not, I'm sure there are discussions of techniques on the web. Basically, most glass cuts very cleanly if you first score it (to concentrate the stress) and then rap the score line. Cutting the kind of glass used for a picture tube may take more work; I don't know how thick the gun neck would be.

Note: I believe the phosphors are also considered a hazardous material. You might want to do this outdoors. Which means you might want to wait for summer. Which would give you more time to research the best way of doing this.

What advantage would there be to doing this outside?  Regarding what you said about the phosphors, are there any precautions I should take to prevent being exposed to it?  And finally instead of using a dedicated glass cutter could I use a pipe cutter (the wheel type) such as those used to cut copper pipe?  I believe the wheels are coated with diamond.

IFyou discharge the tube properly.  And IF you release the vacuum properly it should not be too dangerous to take off the neck.  I'd use a glass cutter and score around the neck and break it off.  I don't think you can saw it off unless you use a diamond blade.  YOu still have to be careful of glass chips and dust.

I don't know what other dangers there may be, but you are the one taking responsibility for what your actions are.