flat screen deposits

poop?

does it wipe off with a moist rag?

Seems water soluble. They come off by scraping, or crushes into dust. I don't see this anywhere else.

Greg

very weird, never seen anything like that.

Somebody sneezed on the back of the set?

Cheers

Phil Hobbs

Back in the day many moons ago, when crt sets like this came into the shop showing "spots", we put them in plastic garbage bags, then sprayed bug killer in and let them sit for a couple days. They were usually full of dead cockroaches when the back was removed.

I prefered knock off blu-shower on roaches. You could tell by looking a customer if you had to lay out newspaper on the bench before opening stuff up.

They stopped accepting cable decoder box returns at the HQ of a cable company here as it lit up the office. They put the boxes under a tarp and roach bombed them over at the warehouse or something like that.

Anyways, that stuff doesn't look like cockroach poop at all. It looks like the crud you get when moving ceiling tiles around, but that would not make splotches or coat the back of a TV set.

I had another smaller visio in same position, no spots. Current is coby.

Greg

Since your removal methods did not affect the underlying plastic, and since plastic is not water soluble, I'll assume that it's not something originating from inside the plastic. I'll also assume that there was no spots on the front of the TV, or you would have mentioned and photographed it.

Mold growth tends to be flat, while your spots have considerable depth. The irregular shape and consistent color eliminates food splatter. The lack of any deposits on the metal mounting bracket indicate that it wasn't delivered by any airborne means (such as plaster, Fix-all, cooking flour, ceiling tile patch, etc). The partial photo of the bracket suggests that it's a wall mount bracket. I would normally guess(tm) a spider infestation, but spider droppings are usually black or brown, not white. The also land on horizontal surfaces, not vertical.

So, what likes to stick to vertical plastic surfaces, doesn't stick to painted metal, is white, powdery, and has to be scraped off. Bingo. Packing material. The TV was probably stuffed back into its shipping box without the usual plastic bag. While styrofoam is not water soluble, some of the recycled paper fake peanuts can be cleaned off. Same with the packing made from pop corn, soy, agricultural waste. To sterilize it, the stuff is sometimes bleached. The metal mounting bracket was added later, which explains why there's no packing material stuck to it. The person that installed the TV on the wall cleaned the visible front of the TV, but left the back a mess. Humidity cycling eventually hardened the packing material. Nobody noticed until the TV was removed from the wall.

"When you eliminate all other possibilities, what remains, no matter how improbable, is the answer." (Sherlock Holmes).

Incidentally, I have a rather nice Olympus microscope in the office that I occasionally use for such computer forensics.

maybe it's melamine and asbestos leaching out of the chinese plastic?

I'd buy this explanation.

I'll send you an invoice.

I was wondering how to verify my guess. If there's enough of the white stuff available, try setting fire to it. If it's a paper or soy derived product, it will char, burn, and crumble to ash. If it's styrofoam, it will melt, burn, and then harden into something that feels like a lump of hard plastic. If it's spider droppings, it will stink like manure. If it's drywall, fix-all, or texturing, nothing will happen.

Incidentally, you can also use this method to distinguish between natural fibers and synthetic fibers.

I never though about burning nylon smelling like "Boiling green vegetables (string beans or celery)".

strange.

Brilliant investigation. The stuff was not there when installed a year ago. I don't currently have a microscope, but I'll try to get whatever magnification I can come up with. The stuff sticks pretty well. I would hate to look inside.

Greg

Thanks. Sherlock did it better.

Oops. That blows my packing material theory. The packing material would need to have been stuck to the plastic case when it was first installed. Argh.

How about something simpler? Can you determine the texture? Is is hard as a rock, grainy, more like ashes, crumbly, greasy, mushy, etc? Does it feel heavy (like sand) or is it light (like ashes). Might was well determine if it's water soluable.

I don't think it will bite.

The texture is firm. It will smash with fingernail to dust. I think it dissolves from what I see. More testing.

Greg

We have the same thing on the back of our TV. Wiped it off once and it's back. ?? Not from bugs. Almost looks like mold but it is not. We don't have this on any other surface. It's flaky.

I still have the tv. Must be something in the plastic ?

Greg

So, have you got a popcorn finish on your ceiling? And, has it taken some damage?