Remove white coat from dark plastic/Keys after washing

[Dallas_Green]

Hello,
Does someone has experience with the removel of this white coating from black and dark plastic after cleaning? There is some advice on the net regarding that and I tried several things but it seems that this coating is not really coming off anymore.
You can see it here on the left side. Some keys are more affected then the other.


I already tried vinegar and oil. Not working very gould. I recognised that with scrapping its getting better, but this takes up to 15 mintues each key and I didnt want to damage the surface of the plastic too much and making it dull.
They are also saying that treating them with gasoline or heat Would help to bring up again the colour pigments. But come on, 40 years old plastic and then such rough methods? There won't be a second chance for this old Robotron keys And such keyboards are very hard to find.

Thanks in advance, guys

 

[1944GPW]

I would be hesitant to try any solvents or heat. Perhaps you could try hand polishing with a soft cloth with a little bit of buffing rouge on it, the type that often comes with Dremel polishing mops. Jerry Walker restored some ASR33 keys that were very chalky and whitened by polishing in a lathe jig as shown here

 

[cfbsoftware]

I would try treating them with Armor All Protectant.

 

[Dallas_Green]

I would be hesitant to try any solvents or heat. Perhaps you could try hand polishing with a soft cloth with a little bit of buffing rouge on it, the type that often comes with Dremel polishing mops. Jerry Walker restored some ASR33 keys that were very chalky and whitened by polishing in a lathe jig as shown here

Not sure if this is something feasible for my keys. I mean, i couldn't mount them on a srew driver nor polish each single key for half an hour Ever seen a keyboard of a Robotron 1715?

Maybe I'll give a try to this kind of plastic repair products like suggested or like this one. What do you think? Will it last for a while?

I was hoping that someone may has experience with that. I already got two keyboards with that broblem and I did wash them just with some smoth soap in water. No idea why this harms the surface that badly. Next time I'll leave the soap off. The other keyboard is from an Amstrad CPC646, a quite common machine (i used a different soap there).

 

[1944GPW]

Ever seen a keyboard of a Robotron 1715?

No, I haven't. I've never even heard of this machine.

Maybe I'll give a try to this kind of plastic repair products like suggested or like this one. What do you think? Will it last for a while?

I had a search for what active ingredients are in that product, and did not find any information. You may have better luck as you're in the country it is made in, so you could contact the manufacturer for details.

 

[Timo W.]

Did you use highly-concentrated IPA to clean the keys? Some plastics react with IPA resulting in fogging, which seems what happened here. It's surface damage that you can't just wipe off.

You should never used anything but soapy water to clean key caps.

 

[Dallas_Green]

Did you use highly-concentrated IPA to clean the keys? Some plastics react with IPA resulting in fogging, which seems what happened here. It's surface damage that you can't just wipe off.

You should never used anything but soapy water to clean key caps.

No, I just used soap water. I was aware of the negative effect of IPA on plastic surfaces.
This is what makes me wonder. I just let the keys 1 day in soap water and then cleaned them off with a brush. After drying they looked like on the pictures
Not all.of them, but the majority.

 

[1944GPW]

Timo's comment about IPA affecting plastics is a good one, I recall having encountered this ill-effect myself. Just a further comment on polishing is that you could perhaps try some thinned toothpaste on a piece of wet cloth to lightly burnish the key. You could fashion a dop from a bamboo chopstick carved to a thick blade (bamboo being less likely to break off than the cheap pine ones) that snugs into the key stem socket so you can hold it conveniently.

 

[gary286]

My first thought was hard water stains but that should clean right off with the vinegar and oil treatment. This sounds more like the white oxidation that forms on automotive plastics and headlights. I would second the vote for armorall or other automotive "dressing" for a quick fix but it sounds like a good brushing down of each key with a light polish is the only permanant solution I can think of.

 

[durgadas311]

Here is what the telephone collectors (and professionals) have used to clean plastics. It seems to me that keyboards fall into that same category, with "high-touch" surfaces.

Definitely never use alcohol, ammonia (Windex!), or solvents on plastics. Warm water with a mild (dish) soap is often recommended, or else something like this:

NEW GENERAL TELEPHONE CLEANER - Arrow Magnolia

NEW GENERAL TELEPHONE CLEANER (Cleaners/Degreasers). An industry-standard for over 50 years, NEW GENERAL TELEPHONE CLEANER is trusted by the largest telecommunications companies in the world for cleaning of telecom equipment. Removes grease, stains, gum

www.arrowmagnolia.com

I did not do a search, but hopefully you can find it for sale in individual bottles somewhere, or find someone whose willing to buy a case and play distributor.

 

[durgadas311]

As far as repairing these key, the damage may have been done (I hope not). It's possible that use will add skin-oil and help hide it. DO NOT use pertrolium products (machine oil, etc) as they can soften the plastic. If it does really buff out, then gently doing that may be the answer. These appear to be "double-shot" keys and so will tolerate buffing without losing the legends. Look at the back side and if you can see layers of both white and the key color (black/red) then they are double-shot and the legends are permanent.

 

[Dallas_Green]

The thing is that I didnt do anything to the keys but putting them in soap water...
Before, the keyboard and it's keys looked like seen in the attachment. Dirty, but actually black.

Yes, the keys are made of two layers.
I'll review your links. Thank you!

 

[durgadas311]

Possibly something more than just dust fell on the keyboard during storage. I don't think the manufacturer would have put some coating on the keys, as they are designed to wear "gracefully" as-is and any coating would start to come off as soon as they were used. But who knows how it was maintained and what someone might have done before storing it. They may have thought nothing about spraying it with Windex and wiping it down.

FWIW, I'm not a fan of ArmorAll, perhaps because I bought too many used cars that had been slathered all over with it. It takes forever to stop feeling greasy. I'm just wary of the long-term effects of it. I'm reminded of the parable of the old lady that swallowed a fly: heaping more stuff on top of a problem usually just makes a bigger problem.

 

[Timo W.]

Before, the keyboard and it's keys looked like seen in the attachment. Dirty, but actually black.

That white powder or whatever it is does not look like normal dust or dirt. Maybe cement abrasion or something? So my second guess would be that this contaminated the water you used for cleaning and the texture of the keys was a good place for it to settle down, which also makes it hard to remove. And some keys are probably more smooth than others (due to different wear) resulting in some being less affected.

You could try WD40.

 

[durgadas311]

That white powder or whatever it is does not look like normal dust or dirt. Maybe cement abrasion or something? So my second guess would be that this contaminated the water you used for cleaning and the texture of the keys was a good place for it to settle down, which also makes it hard to remove. And some keys are probably more smooth than others (due to different wear) resulting in some being less affected.

You could try WD40.

I would advise against WD-40 or any petroleum product. You might get away with it, but it's risky. If you must, at least follow up with some sort of rinse that will remove any residual WD-40 - however that may require things like alcohol so you're back to adding more risk.

 

[Dallas_Green]

So my second guess would be that this contaminated the water you used for cleaning

This might be an explanation, although I changed the water several times at the beginning due to the hight amount of dirt and particles in it.

Well, however. Now it's about restoring what's left behind

 

[durgadas311]

This might be an explanation, although I changed the water several times at the beginning due to the hight amount of dirt and particles in it.

Well, however. Now it's about restoring what's left behind

I keep jugs of distilled water around for this purpose. Possibly even do two rinses, first with tap water and finally with distilled. But these look more like something invaded the surface of the plastic, otherwise I'd expect it to wipe off easier.

 

[Dallas_Green]

Here is what the telephone collectors (and professionals) have used to clean plastics. It seems to me that keyboards fall into that same category, with "high-touch" surfaces

Does that little bottle cost $170!?

 

[DougM]

I wonder if there was some sort of shellac coating on the keys to begin with and that's what's turning white. If that's the case then they won't really clean up and maybe your only hope is to re-coat?

Can you shellac shellac?

 

[Timo W.]

I would advise against WD-40 or any petroleum product. You might get away with it, but it's risky.

You always try on a single, unimportant key first.

I never had WD40 do something bad to plastics. But of course, there's always a risk, no matter what you try.