Many thanks to SWLing Post contributor, Jason, who writes:
Hi Thomas,
Recently I was cleaning and foolishly decided to clean the face of my Tecsun PL680 with 90% iso alcohol using an ear cleaner / Q-tip. Now the LCD has a smudge look to it, almost like a fog. The display is still legible thankfully, but only when looking head on. I quickly wiped it down with a cloth and left it in an airtight container filled with silica gel packets for a week.
Would you or other SWLING readers have any idea how to remedy this? It is my understanding that this is just cosmetic damage and shouldn’t impact the usage of the radio.
Regards,
– Jason
Sorry to hear about this, Jason. Yes, isopropanol/isopropylalcohol is a solvent and can corrupt plastic surfaces like this. I’m familiar because my wife once tried to clear a DVD with 90% isopropylalcohol and it made the surface so hazy, the DVD player could no longer read it. I don’t think this will have any impact on the radio itself since you didn’t exactly did it in iso alcohol.
I understand that in some cases, polishing the surface can minimize the haziness, but how to do that, I’m uncertain. My hope is, another SWLing Post contributor can chime in with some real-life experience!
Please comment if you can help Jason!
Meguir’s Plastx. I use to polish up all of my older radio screen dial covers, good for plastic watch dials and turntable dust covers also. Gently rub it on with a cotton ball.
Plus 1 on the Novus #2.
I thought I ruined the dial of my Tecsun PL-360 with contact cleaner. Novus cleaned it up perfectly! (Fixes acrylic watch dials too!) Use the lower strength, not the big scratch level.
You can’t unmelt the melted plastic
which is what had happened.
Any cures are a bodge.
Maybe anon.co can be persuaded to acquire spare plastic covers ?
just a quick one.. you can make it clear again for a short time (maybe a few days) simply by putting a little bit of machine oil on your finger and rubbing it on the screen. Sewing machine oil is good, but wd-40 type of penetrating oil will work, but it smells!
The oil has about the same refractive index as most perspex so it fills the tiny pits on the surface that makes it hazy, so it magically becomes clear again. Of course this will only work until the oil goes away…
Agreed on the earlier toothpaste comment, as it is a decent micro-abrasive cleaner.
Another option might be PlastX. It is a diminishing micro-abrasive. I have used it on many plastic surfaces, both clear and even some colored, on cars and more. Many car parts store stock it, too.
https://www.meguiars.com/automotive/products/meguiars-plastx-clear-plastic-cleaner-polish-g12310-10-oz-liquid
My suggestion to try: Put a little bit of mosquito repellent which has DEET on a cotton cloth. Test a small section of the plastic first by rubbing it with the cloth. This trick is used to clear up the foggy plastic headlight lenses, much cheaper than purpose-sold lens defogger.
Careful with the Deet. It actually melts the plastic surface. You cannot keep going over it with a cloth, because it will eventually stick to the melted surface. Just do one quick wipe. I only recommend this for a major repair like an old car headlight.
Mequiars Show Car Glaze #7. I’ve been using this stuff for over 20 years on polishing plastic. Just a little dab will do you on clean soft rag. Repeat as necessary. 73 Bob
Magic Eraser
flitz polish or simichorme polish and a soft cloth, you can find either product on the internet.
use making small circles across the screen, the depth the alcohol penetrated will determine
your success.
Good Luck
Art
I usually use goo-gone if I need to clean off something or even polish it and that’s if the plastic is already hazy, if that’s the case, I usually only use alcohol when trying to clean off the internal circuitry when I’ve bought a radio where someone allowed the batteries to leak alkaline fluid and coat/short out the soldered points.
On circuits, if I dare use a harsh cleaner I only do so by using a hair dryer to dry out the circuitry afterwards.
The first XHDATA D-808 I ever bought arrived with what looked like a permanent distortion in the display window, I tried polishing it but the polarized distortion never went away, so my remedy for that was I was forced to remove the plastic display window until only the glass, (I assume it’s glass) LCD display remained, problem solved, but now that unit is permanently disfigured appearance-wise, but it works and I can clearly read the display as it should be seen.
Fast-forward to a few years later and I took a chance and found a good deal on another unit, thankfully, this 2nd unit did not suffer from a distorted display window, just a bad unit in the past plastic-window-wise I suppose.
Maybe some polishing compound like is used for headlight lenses ?
I scrolled down to suggest the Novus #2 route but TheZ beat me to it. I totally concur. The Novus kit above is a good deal and will last you a long time most likely. Just be gentle, take your time, and try to polish evenly. Resist the urge to speed anything up using anything mechanical (I learned this the hard way with those little felt pads on a Dremel).
I highly recommend this kit. For your situation, I just recommend using #2 followed by #1. Keep #3 for deeper scratch removal. I have purchased display model electronics with scratched or hazy displays, and this kit made the windows brand new!
https://www.amazon.com/Novus-7136-Plastic-Polish-Kit/dp/B002UD0GIG/ref=sr_1_6?keywords=plastic+polish&qid=1637410115&qsid=140-1968908-0344169&sr=8-6&sres=B002UCYRZU%2CB002UD0GIG%2CB0000AY3SR%2CB0029B518O%2CB0000AXMD2%2CB0025QZMRI%2CB000MUSOW4%2CB071FRWWRF%2CB001DKJU8Y%2CB002UD0GFE%2CB000B4UGZE%2CB002UCYS0Y%2CB00068KU1K%2CB002UD0GGS%2CB0000AXNJS%2CB00092CKN4%2CB075T2GFKC%2CB000ABB1P2%2CB0000AY2AP%2CB08DL1ZPKC
I suggest…. toothpaste at first. It is mild and free. Next “harder” stuff will be ceraclean, a produkt for cleaning ceramic surfaces of your oven. Perhaps you have something similar on hand…
I use this regular for polishing the hesalith/acrylic watch glases of my collection of vintage watches.
vy 73, Arno