68kMLA Classic Interface

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Vinegar screen on my Powerbook G3 "Pismo"?
Posted by: fergycool on 2025-10-04 08:55:01
I've been playing with a Powerbook G3 Pismo that I acquired recently. Works great. I popped in a mSATA card + ATA adaptor I had already lying around (bought for a G4 Mac Mini) got Mac OS9 running and I'm really enjoying it!

Only issue is the screen. It has these two large patchy areas. From googling and reading on here it seems I have the "acetic acid" issue although what I see looks very different to what I can see online! From the photos below would this be the case? If so it appears I need to replace the polariser screen. Any handy tutorials about?

Thanks!
Cheers
Ferg

IMG_5243.jpeg
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Posted by: Byrd on 2025-10-04 21:15:08
It looks like vinegar syndrome noting the diagonal striations. I just came across my PB540C with similar distribution/lines seemingly happened overnight. The tutorial is you need to painstakingly remove this adhesive layer, apply lots of isopropyl alcohol onto the bare LCD and experiment with different polariser films to find a match.
Posted by: fergycool on 2025-10-05 01:59:47
It looks like vinegar syndrome noting the diagonal striations. I just came across my PB540C with similar distribution/lines seemingly happened overnight. The tutorial is you need to painstakingly remove this adhesive layer, apply lots of isopropyl alcohol onto the bare LCD and experiment with different polariser films to find a match.
Thanks a lot for that! By experiment I guess you mean the angle of the film?
Posted by: Byrd on 2025-10-05 02:06:53
Yes - the film itself has an angle (0, 45, 90 - it's probably 45) and then you often need to rotate the film around to get the correct polarizer alignment - hence buy a larger sheet to compensate for this. Forgot to mention the isopropyl alcohol use is to get the sticky glue off (which stinks of vinegar), and wear gloves as running your fingers near the glass edges can cut them easily.

Currently going through a land of hell fixing the polarizer film on my PB540, noting it had degraded films front and back but the Pismo should just have one I believe.
Posted by: 3lectr1cPPC on 2025-10-09 10:04:49
Film angle should match the angle that the scrapes/stripes are going. Hard to tell with the "blotchy" form of it here, but I think it would be 45 degree.
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