Jump to content
IGNORED

New technique for whitening yellowed plastic


adam1977

Recommended Posts

Removed XEGS buttons from it since I am guessing the dye would degrade in the sun. The buttons aren't yellow anyway. Faded yes but not yellow. The bag clip is a simple color gauge, just for the photo.

 

I got this XEGS from B&C 'new old stock'. Well it was a returned product to Atari. It was golden tinted when I got it a couple years ago, to my mild disappointment. I don't think it was B&C's fault, since the keyboard is not yellowed at all. I think it was heat-caused in Jack's cheap 'just make it work' ghetto storage but who knows when.

post-49049-0-71782400-1558113263_thumb.jpg

Edited by Sugarland
Link to comment
Share on other sites

I would hope the sun would not adversely affect the dye in the XEGS buttons, otherwise it would (presumably) also adversely affect the dye in the case plastic. I've treated XEGS console buttons using Peroxide in the past with no issues.

 

Anyway: if this proves an effective long-term solution, it will be good news (although not so much for those in the UK, which has very limited direct sun). The effects of 'traditional' Retr0Briting treatments have not proved long-lasting in my experience, and the risk of irreparable damage (via 'blooming', etc) is great (I don't buy into the idea that the Peroxide makes the plastic especially brittle; never noticed that, at least).

Edited by flashjazzcat
  • Like 2
Link to comment
Share on other sites

Will attempt the sun trick when this damn place gets some proper long term sun, teaming down at the moment and looks miserable as sin. AT least my gear would not be stolen in this, only the mad kids and the odd dealer about at the mo :)

 

I got the peroxide in to do the retrobriting but never got to do it and then I saw all the posts re streaks and blooms, put me right off, yellow is bad enough but part yellow with streaks is just wrong..

  • Like 2
Link to comment
Share on other sites

I'm in mid process of doing a 130Xe and so far it's looking good.

 

Already done my other A8's under the fiddly retrobrite process.

 

I'm half way through a BBC Master which the top half is light cream (after 16 hrs) and bottom still yellow and away to get exposed for around the same time. Acorn Electron also getting the exposure)

 

Amazed how much less trouble it is to do it this way and Not have a peroxide bath, stingy fingers and UV glare to deal with :0)

Edited by Magic Knight
Link to comment
Share on other sites

Another key take away from that video...

 

GET RID OF ALL YOUR FLUORESCENT BULBS INCLUDING CFL'S! Replace them with LED.

 

Or at least, keep all your equipment away from fluorescent / CFL's.

 

(I always hated CFL's anyways... so good riddance!)

Keep away from LED!!! It can (and most likely) interfere with RF signals such as WiFi, Cell-phone etc.

 

even merchant shipping is moving away from LED-lighting.

  • Like 1
Link to comment
Share on other sites

Well, amazing cleaning results can be achieved that way, but the effects do not extend to removing yellowing caused by Bromine in the plastic. You can scrub all day and that s**t ain't coming out.

 

Some people simply aren't bothered by the yellowing, of course, but for those of us who are, there seems to be no long-lasting solution other than sourcing machines whose cases still have not yellowed after thirty-five years, and - if well cared for - will probably not yellow for another thirty-five years. They definitely come up nicely with soap and water alone.

  • Like 1
Link to comment
Share on other sites

Someone posted this on #retrobattlestations today

 

https://imgur.com/gallery/0SdpDJ6

 

Wow. I wonder what the lightbriting temps were. Is it the heat or sunlight or both that makes it brittle? How was it stored after lightbrighting? Or maybe it was already brittle before the process. It was very yellow. A sample of 'one' is not enough to be sure of the cause or that sunlight alone does this.

Edited by Sugarland
Link to comment
Share on other sites

heat is often key for reactive processes. Keep cool. I've had someone tell me cleaning the plastic too much could open it's pores and ruin it, but nothing has gotten brittle or fell apart yet. depends on what the stain or discoloration is, and what the plastic is. As for the bromine, the flame retardant migrating to the surface etc. after a quick read, the yellow appears to be very shallow at the surface of the plastic. not sure why anybody wants to heat the plastic up and use high concentrations of peroxide or UV to deal with it... it looks like a case of less is more. I think there is some 1970's information floating around about premature yellowing of plastics and dealing with yellowing and off tint greying of keyboards, and other household plastic items.

 

Heat and certain UV light bands degrade the plastic pretty harshly.... Too bad they want to imprison incandescent light bulb users....

Edited by _The Doctor__
  • Like 1
Link to comment
Share on other sites

look to iron, calcium, and zeolite to capture and remove the migrated bromides and related oils if heat and uv were the culprits, if the shine is lost a super light acetone mist cast restore the shine. depending on the related bezels and plastics used methyl hydrate/methanol can handle browning and greying. always go weak with the treatment and heavy with the elbow grease.

to remove paint and such glop dettol works over time. (Dettol is a sanitizer) though I've used Listerine variants over time.

 

In another thread, mechanerd / Kevin also noted a solution we used back in the day that cleaned things very well. We were probably talking about trs 80 stuff at the time... or radio shack or something

 

I've used all of the above at one point or another, including baking soda, calcium bicarbonate, vinegar, and elbow grease.

 

Pick the correct stuff for the given plastic, start with weakest safest method / cleaner and work your way up. All of the other methods I keep seeing using heat and high concentration chemicals/peroxide look like they speed the death of the plastic, bleach the problem and need to be repeated often. A UV protectorate and air conditioning seems a good idea, and those incandescent bulbs are gold it would seem.

  • Like 1
Link to comment
Share on other sites

All of the other methods I keep seeing using heat and high concentration chemicals/peroxide look like they speed the death of the plastic, bleach the problem and need to be repeated often. A UV protectorate and air conditioning seems a good idea, and those incandescent bulbs are gold it would seem.

 

anecdotal evidence, my first apple IIc when I got it was mustard yellow when I got, a good warm bath got it a half shade less brown, dollar tree peroxide + oxy and a day being submerged in sun got it snow white again. With in a couple months it started turning beige again not exposed to light (unless I was using it) in a climate controlled room, it settled on being a light beige for the next 4 years until I sold it (cause I got a mac with a IIe card setup)

 

so repeated often, not so much, its not going to be perfect brand new though, just like anything with some time but I agree most retro bright solutions I see (as I harp this point again) are using weapons grade chemicals which will and does bleach the problem (IE the8 butt guy's osbourne wasnt darn near white when new)

 

with my own experiments with the stuff, the oxy clean and sunlight do more than hydrogen peroxide, when I did my 65XE it sat out there for half a day without oxyclean (dollar store brand of course) without much effect ... a scoop of that crap dissolved in hot water and added to solution and it kick started it quite nice and it was more or less done (keys being stubborn cause they float around) by that evening

Edited by Osgeld
  • Like 1
Link to comment
Share on other sites

I recently, (a few months ago) retro-brightened my 800, 810 and all of my XL peripherals by the now old-school way of using clear plastic tubs, and a LOT of peroxide (at $.90 a bottle at Walmart I splurged and bought 20 bottles) a bit of water and submerged all the yellowed casings for two days in the sun and one night under direct spot-light (this was in between the two days and didn't really seem to do much) and they turned out great. But one of my 1050's has some upgrades and RS232 ports mounted to the case and so it was out of the question for me to disassemble it without a ton of work. So I was going to mask and paint it like I did my 1200XL after it received body work from a PBI installation. But this sounds like a wonderful option and worth a try, since I am in Oklahoma and this time of year we get tons of sunlight. :thumbsup:

Edited by Gunstar
Link to comment
Share on other sites

2x days in the UK sun certainly improved my lazer 1050 - see pic

altho i shouldve put the entire drive outside and not just the upper half...!

fortunately, today is another mild day weatherwise so its back to the great outdoors for another stint :)

 

 

post-38211-0-57213800-1558162616_thumb.jpg

  • Like 5
Link to comment
Share on other sites

  • 2 weeks later...

Oops, for some reason (thick) I saw the post from Major Havok and thought it was linked to XrBrevins UK picture (no glasses on)

 

Hoping for some newer UK pics with the spread of sunshine showing any differences in detail, it obviously works but is the UK's shine / UV powerful enough for the bleaching..

Edited by Mclaneinc
Link to comment
Share on other sites

there seems to be no long-lasting solution other than sourcing machines whose cases still have not yellowed after thirty-five years, and - if well cared for - will probably not yellow for another thirty-five years. They definitely come up nicely with soap and water alone.

 

this ^

I buy dead old 800XLs just for a nice case.

any that are out "in daylight" I keep covered in fleece (light-proof) dust covers - when not in use

Link to comment
Share on other sites

Old vs new on my 1040STE, after about a day and a half in the sun.

 

nice. but you can still see there's a difference

the yellow is now the colour that the rest of the case was and

the rest of the case is now slightly lighter still.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...