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Removing Yellowing from Plastics - Part 4

helion said:
I made a solution of Vanish (another of those Oxy type of products) : about 120g in 8 litres of water. It is active even in the night, letting off bubbles and all. Its packaging did not make any mention of the concentration of the sodium percarbonate.
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Trust me: it isn't doing any de-yellowing at night (without UV lights).
It may be bubbling (which is probably caused by the Vanish itself), but there will be no de-yellowing - UV is needed to make the process work.
All it's doing at night is getting wet - it might make it look cleaner in the morning, but that's probably just old nicotine/tar being washed off by the bubbling.
 
The Vanish solution did not yield any good results apart from a very light effect on the letters of the keyboard, but there was a good and visible effect towards the sun facing side when 6%H2O2 + a pinch of Vanish in equal amount of water was used. A gel made of clothing starch yielded patchy results.

On that note, was egg white tried as a gel base for the retr0bright formula?
 
helion said:
The Vanish solution did not yield any good results apart from a very light effect on the letters of the keyboard, but there was a good and visible effect towards the sun facing side when 6%H2O2 + a pinch of Vanish in equal amount of water was used. A gel made of clothing starch yielded patchy results.

On that note, was egg white tried as a gel base for the retr0bright formula?
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Thanks for reporting those results.

I haven't tried egg white myself.

Tez
 
Although the question came up once and our present method here
was not applicable, nevertheless......is there any known or similar
method out there for reviving transparent plastic like car's light lenses.

ziloo
 
ziloo said:
Although the question came up once and our present method here
was not applicable, nevertheless......is there any known or similar
method out there for reviving transparent plastic like car's light lenses.

ziloo
Click to expand...

Here in the UK people buy kits that use very fine wet n dry paper and a slightly abrasive polish to remove the clouding that occurs on polycarbonate car headlights. Had to do it to my 2003 VW Passat.
 
Thank you Chris for your response. In this case, the plastic has
yellowed and although I haven't tested it thoroughly, I think the
yellowing is all the way to the core. The UV can penetrate through the
transparency and affect the whole media and not just the surface.

ziloo
 
ChrisCwmbran said:
Here in the UK people buy kits that use very fine wet n dry paper and a slightly abrasive polish to remove the clouding that occurs on polycarbonate car headlights. Had to do it to my 2003 VW Passat.
Click to expand...

Ugh don't remind me. Time for me to do it to my PT cruiser yet again! >.< Stuff only lasts a few years sadly...

Now egg whites seems interesting! I might have to try that! I don't use retrobrite much, but I do have an apple IIc that is uber yellow/brown/70s gold I am itching to try this out with!
 
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Hello everybody

I'm Alberto from Italy and I want to restore my Commodore 64C (very yellow)

I read a lot of things about Retrobright (also that there are a lot of guys using not the original formula)

I want to use the orginal formula but I've a problem...here we don't use as measure units "tablespoon", "teaspoon", "cups" etc but only milliliter, grams, etc....and so I don't know what is exactly a tablespoon or a 1/4 teaspoon measure!

I asked to "vecchi computer" (a italian site which talks about RetroBright) but the autor told me to be "generic" and that if I use more or less xanthan or glycerine or Vanish there aren't problems.

Instead my Retrobright was very very very dense, difficult to spread on components, no visible effects adding vanish oxi and also no visible (or very low) effects on the plastic after a day out :(

(I'm tring on a 2001 Pc keyboard with yellow keys to test the product...not on the C64, but anyway very low good effects but also no bad one)

SO!

Please! Could anyone convert for me in grams (or oz. is the same!):

2 heaped tablespoonfuls of Xanthan Gum
1 level teaspoonful of Glycerine
1/4 teaspoonful of "Oxy" laundry booster


thank you!!:D
 
in the UK for cooking I use a Heaped tablespoon for flour etc. as 1 oz (or 25g)
a level tablespoon (of liquid) is about 20g
there are 4 uk teaspoons to the tablespoon so 5g (same as a 5ml medicine spoon!)

so...
40g - 50g Xanthan Gum
5g Glycerine
about 1 or 2 g "Oxy"
 
nige the hippy said:
in the UK for cooking I use a Heaped tablespoon for flour etc. as 1 oz (or 25g)
a level tablespoon (of liquid) is about 20g
there are 4 uk teaspoons to the tablespoon so 5g (same as a 5ml medicine spoon!)

so...
40g - 50g Xanthan Gum
5g Glycerine
about 1 or 2 g "Oxy"
Click to expand...

Thank you very much! :D

Other questions...

I think that the follows are simple questions and so I tried to search the answers in the threads...but without luck.

2g of Oxy is a very little bit quantity in 500ml peroxide.

1-Are there any problems using too much Oxi ?
I mean: I know that using too strong peroxide can cause problems, is it the same with the oxi dose? Are there any contraindications?

2-Do I have to note a reaction (foam for or bubbles for example) adding oxi to the gel or it has to remain "stable"?

3-At the end, with the original formula, is RetroBright more similar to a gel or to a foam?
 
Hello Alberto and welcome to the forums!


1-Are there any problems using too much Oxi ?
Yes there are!In fact a bigger oxi dose has a bad effect on the plastic surface.See tezza's blog here:http://www.classic-computers.org.nz/blog/2011-04-11-lisa-keys-retrobrighting-misstep.html

2-Do I have to note a reaction (foam for or bubbles for example) adding oxi to the gel or it has to remain "stable"?
Ι have never noted anything when adding oxi to the gel.You can see bubbles if you make a liquid retrobright solution. Look again at tezza's blog http://www.classic-computers.org.nz/blog/2010-10-03-2nd-sys80-keydeyellow.htm

3-At the end, with the original formula, is RetroBright more similar to a gel or to a foam?
With the original formula retrobright is similar to a white non-transparent mixture (something between gel and foam!)
 
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ziloo said:
...is there any known or similar
method out there for reviving transparent plastic like car's light lenses.
ziloo
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Slightly O/T
Years ago we used this stuff http://www.sylmasta.com/acatalog/Online_Catalogue_Micro_Mesh_Abrasives_1.html for re-polishing acrylic & polycarbonate that was scratched. One of the guys in the workshop used to do helicopter windscreens with it. Important tip - initially use an abrasive that gives scratches as deep as the ones you're trying to polish out, then work finer.
 
angel_grig said:
Hello Alberto and welcome to the forums!


1-Are there any problems using too much Oxi ?
Yes there are!In fact a bigger oxi dose has a bad effect on the plastic surface.See tezza's blog here:http://www.classic-computers.org.nz/blog/2011-04-11-lisa-keys-retrobrighting-misstep.html

2-Do I have to note a reaction (foam for or bubbles for example) adding oxi to the gel or it has to remain "stable"?
Ι have never noted anything when adding oxi to the gel.You can see bubbles if you make a liquid retrobright solution. Look again at tezza's blog http://www.classic-computers.org.nz/blog/2010-10-03-2nd-sys80-keydeyellow.htm

3-At the end, with the original formula, is RetroBright more similar to a gel or to a foam?
With the original formula retrobright is similar to a white non-transparent mixture (something between gel and foam!)
Click to expand...

Yes, you beat me to it. I was going to post up that unfortunate experiment of mine.

You can certainly overcook things using too much. It's not just the active ingredient in "oxy" but there are other things in those laundry activators as well. Who knows what too much of these do. While experimenting I have used a concentrated "just oxy" mixture with some success but this was only on straight white/cream plastic with no markings. You've read what happened to the keys (i.e. damaged).

I tried these experiments because my supply of H2O2 was a lot more expensive than the laundry activator. However, if you can get/afford hydrogen peroxide I would use that, and I would stick with just the small amount of Oxy recommended in the retrobrite recipie. I wouldn't try to boost it.

The recipe that's worked best for me is Lorne's Xanthan gum/glycerine variation from the original recipe (except I used 6% strength H2O2). It's on the wiki. It forms a light gel you can paint on easily. If you can't get Xanthan gum, my own arrowroot variation will suffice, but it does tend to crust up, which may not let as much light through as you would want. Also, my technique/recipe does tend to make it foam more and it's easy to accidently overheat it.

Good luck!

Tez
 
It's late spring here in NJ...good time to do some retrobrite when it's nice and dry and not too hot.

Here's an Apple IIe Platinum I just started working on. Decided to try just the lid and then start the rest of the case if things went well (which it appears they did...so I've started the rest of the case today.)

a2e-retro.jpg

Also started on this extremely yellowed C128D keyboard. Here it is before and after one day of treatment. The smooth plastic makes it harder for the retrobrite to stick (whereas the Apple's case is much rougher and seems to hold on to it better.) I think it needs another day and it should be good enough.

128d-b4.jpg
128d-aftr.jpg

The keys need some treatment too but I don't really want to risk fading the keycaps.
 
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The edit button seems to be missing, so I can't add this to the previous message. But here's the completed Apple IIe Platinum. You can see I avoided treating the logo for fear it would fade, so there a little yellowing still visible there. The photo doesn't do it justice. It really looks new.

a2e-retro-done.jpg
 
Hi, I'm new here, I just have a question, is anyone aware of someone that offers restoration services, such as removing the yellowing for older computers, I would rather send mine off to someone and have them do it then mess with it myself?

Thanks
 
Macclassic74 said:
Hi, I'm new here, I just have a question, is anyone aware of someone that offers restoration services, such as removing the yellowing for older computers, I would rather send mine off to someone and have them do it then mess with it myself?

Thanks
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Depends where you are located. I'm sure that those people that have even RetroBrite'd their patio furniture would be more than happy to dazzle you with their ability to make case parts look brand new again.
 
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