Smartphone cover...

Smartphone cover...

Author
Discussion

Simpo Two

Original Poster:

87,066 posts

272 months

Tuesday 25th October 2022
quotequote all
I recently found what I think is an abandoned phone cover. It's 158 x 74mm, just a piece of clear plastic with rounded corners. It would be ideal for the windscreen of a model boat I'm making. However one side felt sticky to the touch - a bit like a Post-It note - so I tried to clean it. Soap and water didn't shift the tack, neither did meths or white spirit. I thought T-Cut had polished it off but it came back. What on earth is the layer, and how do I get rid of it please?

Scrump

22,936 posts

165 months

Tuesday 25th October 2022
quotequote all
IPA (isopropyl alcohol, not India Pale Ale!)

Simpo Two

Original Poster:

87,066 posts

272 months

Tuesday 25th October 2022
quotequote all
Scrump said:
IPA (isopropyl alcohol, not India Pale Ale!)
I had some in stock from the Covid days. No luck. Like the others, you think it's worked, but the moment you touch it it's tacky again.

Could it have some kind of nanoparticle coating?

Ledaig

1,723 posts

269 months

Wednesday 26th October 2022
quotequote all
Could be a silicon cover and all you are doing is cleaning it back to 'good' silicon each time.

Simpo Two

Original Poster:

87,066 posts

272 months

Wednesday 26th October 2022
quotequote all
Ledaig said:
Could be a silicon cover and all you are doing is cleaning it back to 'good' silicon each time.
One side is smooth and shiny, as it should be. The other seems to have an invisible texture on it - you can't see it (it looks clear) but you can just feel it with a fingernail, and has a slightly sticky feel. It immediately shows smudges and dirt.

Simpo Two

Original Poster:

87,066 posts

272 months

Saturday 29th October 2022
quotequote all
Today I tried to cut the screen into the shape required. I cut a paper template, stuck it on and tried to cut round it with a modelling knife. To my surprise the plastic, rather than scoring, cracked in all directions. It was then that it became clear that the sticky layer was actually a thin laminate, and with care could be pulled away from the clear plastic. But the point of the knife made no impression on the plastic; it was as hard as steel. I tried a bandsaw, and the teeth just shattered it. A scroll saw (very fine teeth) was no better. So the smartphone cover went in the bin!