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Registered Member #2909
Joined: Wed Jun 09 2010, 12:31AM
Location: fort belvoir, Va USA ( south of DC)
Posts: 145
Can old TV CRT glass be a good radiation shield? I know there made of lead glass and design to block a majority of X-Rays from escaping from the CRT. So I was thinking would it be a great shielding material, you could grind up the glass tubs and pure them in to side of a form, use one or two front screens as viewing ports for x-ray experiments. It could a relatively cheaper solution then buying lead sheets, which can be expensive to ship. Especially with there wide availability at junk sites and curbs, as people upgrade to flat screens.
Registered Member #2463
Joined: Wed Nov 11 2009, 03:49AM
Location:
Posts: 1546
Big color TV crts contain a lot of lead, pounds on it. If you grind up the glass for remelt, how will you deal with the lead bearing sand? Also the remelted form you create wont look like a CRT, something people have disposal methods for. The other practical thing is that those thing break with shards of glass flying about everywhere, not due to implosion, but because you need a heavy hammer to do it.
Registered Member #2893
Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2242
It might work. I've cut up CRT's before with a dremel. They aren't tempered so you CAN cut them.
The screens are only designed to block 30kVp x-rays though, and I'm not sure that using them to shield 70kVp is a very good idea. Especially if you plan on sitting in front of it!
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Lead sheet is as easy as pie to cut with tinman's snips which produce no dust, easy to shape, safe to handle with rubber gloves, and readily takes paint as an environmental safety shield.
By comparison, first breaking and then pulverizing old TV tubes is completely crackers!
Registered Member #2099
Joined: Wed Apr 29 2009, 12:22AM
Location: Los Altos, California
Posts: 1716
pauleddy wrote ... Can old TV CRT glass be a good radiation shield?
IMHO, it would be silly to use CRT glass as a substitute for lead, except where you want optical transparency.
Then the question is, what sort of optical quality can you get in a salvaged piece of funnel glass (high lead) or faceplate glass (usually Pb-free, with plenty of Ba or Sr, in color CRT's).
I suspect the inside surface of faceplates, after you remove the phosphor, has a matte texture instead of a smooth polish. Maybe I can check one this weekend. Amateur telescope makers would be equipped to change that.
Registered Member #2909
Joined: Wed Jun 09 2010, 12:31AM
Location: fort belvoir, Va USA ( south of DC)
Posts: 145
I was thinking on only using the back part to smash up and use 2 or 3 the face plate a viewing port I don’t want to melt it that would require allot of work, nor grind it in to sand just a descent pile of relatively small pieces that I could mix with water or concrete to enhance it absorbsion of radiation
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