Speaking of saving things from the dump, if you ever have an opportunity to rescue a really large plasma screen TV, here's some advice:
DO NOT TAKE IT!
Earlier this year I was given a very large one. Panasonic TH-50PH11AK, a bit over 1.2m diagonal screen. Hugely heavy.
It was beyond repair (missing input cards) but did contain a large amount of boards with lots of power components, which was what I took it for. Also curiosity; I hadn't dissected a plasma screen before. Stripped it down, (
http://everist.org/NobLog/20170224_summer_vacuum_odyssey.htm#cull ) which left the problem of disposing of the actual screen.
With LCD screens you can just smash the glass and put in the non-recycling roley bin. I'd had it in mind to do the same with this plasma screen. Big mistake.
The construction is (from the front):
* Sheet of protective glass. Which has a transparent conductive layer to prevent EMI emissions from the HV, HF plasma scanning lines.
* Gap, about 1cm.
* Front glass of the plasma screen.
* Very small gap, under vacuum.
* Back glass of the plasma screen, with raised ridges to maintain the gap, and the color phosphors.
* Thin, tough double sided tape, adhering the glass to...
* The aluminum backing plate, with reinforcing bars and mounting posts for all the electronics.
So I had the front protective glass and the separate plasma assembly lying around for a few months, trying to figure out how to break them down. See the problem?
The glass glued to the aluminum plate, makes a very difficult thing to cut up. Making it worse, the phosphors in CRTs are extremely poisonous. Obscure, secret compounds of rare earth elements, but google 'ccfl cut injuries'. For eg here:
http://www.snopes.com/photos/medical/cfl.asp Note that Snopes and most other net articles get this *completely* wrong. They focus on the small amount of mercury in the CCFL bulb (not the cause of that necrotic disaster) but totally ignore the phosphors coated on the inside of the glass. Really, really stupid & ignorant omission. Yay Snopes /s.
Anyway, not a good idea to get those powders in even a tiny cut. Or breathe them. Or leave bits of broken glass + phosphor lying on the ground, for pets to cut themselves on.
First the front protective sheet. Should be easy to break, right?
No. It turns out to be glass laminated front and back with something like kevlar. A hammer merely dents it. To cut it, takes a row of closely spaced dents then a large knife to saw through the plastic sheets and the powdered glass inside. Ugh. Pic1 was before I cut it up, after finding the merely folded piece was still too big to fit in the bin.
Then the metal-glass laminate. I did all the glass-breaking of this under a large plastic bag, to stop glass chips flying all around. The front glass broke off easily, and was binned. That leaves the poisonous, solidly glued-on back sheet. It turns out to be extremely difficult to separate from the metal backing, even in small pieces. That double sided tape is *tough*. Trying to chisel it off, wearing full face mask, heavy gloves, and working with the chisel under a plastic sheet, it obviously wasn't going to be possible to strip the entire thing.
But I couldn't just jigsaw the glass-plus-metal sheet, it would wreck the blade immediately. And I can't angle-grind it, because that will make and spread dust with the phosphor.
The best solution I could think of was to chisel off the glass in minimal lines, then jig-saw the aluminum alone along the center of those lines after clearing the glass fragments. Which worked.
Then the whole area got a very careful sweeping for glass fragments that had escaped the plastic sheeting, followed by obsessive vacuuming. And cleaning all the crap off the jigsaw and other tools.
I won't be making that mistake again.
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