Recolouring Discoloured Vinyl/Plastics

[Kat Manton]

Hi,

I've just thought of something from the classic car restoration 'world' which might be useful for restoration of certain radio sets etc.

Some plastics used for knobs become discoloured over time; one example I noticed is the white knobs used on the blue and white Hacker Sovereigns turning yellow.

Also some of the Rexine/Vinyl coverings discolour.

Kolorbond Ltd. manufacture a range of products which recolour various materials; it's not a surface coating like paint; so doesn't flake off.

I've seen the results of their 'Vinylkote' product, used to recolour a full Sunbeam Rapier H120 interior from blue to red - seats, door cards, the lot. Very impressive. I was also shown a sample piece snipped from under the back seat which was used as a test. Half had been recoloured, half not. This could be flexed, pulled, screwed up - nothing flaked off - the recoloured section stayed perfect.

Disclaimer: I've not tried their products on radio knobs or coverings; but I thought I'd bring it to the attention of forum members as possibly 'something to try'. The 'Vinylkote' seems likely to work on vinyl and rexine coverings; 'Bumperkote' is for hard plastics and may work on the materials used for moulded plastic knobs.

Regards, Kat

[Paul_RK]

Hi Kat,

Certainly looks interesting, though I'm wondering how well it would cope with the milled surfaces offered by those Hacker knobs. And, if truth be told, I directly found myself thinking not so much of the Hackers at all as of a very dingy-looking 25" Keracolor Sphere I have hidden away

Paul

[Nickthedentist]

Sounds interesting, Kat!

All phone collectors will have a few 700-series phones tucked away that are mint - except for having turned a horrid colour after exposure to sunlight followed by storage in a dark place.

The same goes for people who like old computers and peripherals.

But frankly, I like my vintage radios to look a little "vintage" rather than like repros.

Nick.

[Paul_RK]

Originally Posted by Nickthedentist

having turned a horrid colour after exposure to sunlight followed by storage in a dark place...

Oh dear... is it the change to darkness that does the worst damage?
That Keracolor's in a very dark place at the moment. The cupboard under the stairs, to be exact

Paul

[Kat Manton]

Hi Paul,

Originally Posted by Paul_RK

[...]I'm wondering how well it would cope with the milled surfaces offered by those Hacker knobs.

Given the way it works (from their site "Just like its stable mate VINYLKOTE, BUMPERCOAT penetrates the surface of the substrate, bonding itself to the molecules and changing the pigmentation.") I'd suspect it would work well regardless of surface texture.

On the bit of vinyl seat covering I was shown there was no discernable difference in texture between the recoloured and original bit. The recoloured red part looked like it had always been red vinyl, but had somehow seamlessly been joined to a bit of blue vinyl.

And, if truth be told, I directly found myself thinking not so much of the Hackers at all as of a very dingy-looking 25" Keracolor Sphere I have hidden away

Hmm... one of their products might just be what you're looking for - you could see if you can scrounge a small sample from them and try it out in a hidden area. The company could probably advise on the suitability of their products to certain types of plastic as well. Do you know what type of plastic the Keracolor is made from?

Regards, Kat

[Paul_RK]

Originally Posted by Kat Manton

Do you know what type of plastic the Keracolor is made from?

Regards, Kat

I'm sorely ignorant when it comes to plastics from this period. I'd guess at GRP - it looks quite like this one http://cgi.ebay.co.uk/Original-Kerac...mZ180027828234 but is much yellower, and a little older (25" CRT, four button tuner).

Paul

[Nickthedentist]

Originally Posted by Paul_RK

Oh dear... is it the change to darkness that does the worst damage?

I've never read that, but it has happened to a lot of my stuff.

For example, I put a white BT fax machine into the loft 2 years ago when I bought a combined printer/scanner/copier/fax thing. It had lived in a very sunny room but was still snowy white. When I looked at it recently, it was a horrid tobacco-yellow colour on all the exposed surfaces, but still nice and white inside.

The same thing happened to my 746 ivory phones which I put away when I replaced them with DTMF phones some 15 years ago.

And I've seen the same thing with old pianos with ivory keys. Nice and white if you leave the lid open, but close it for a year and you'll be in for a shock when you open it again..

Not sure whether this is reversible to an extent by exposure to more sunlight, but Kat's paint idea might be a good trick to have up one's sleeve (probably not for the piano though).

Nick.

[Sean Williams]

I would reckon the Keracolor would be better off being stripped and painted with a good cellulose, or twopack finish - GRP gets a bit humpy if treated to odd chemicals.....

Cheers
Sean

[GJR 11L]

I used Vinylcote on a pair of odd rexine-covered seats that I once wanted to fit to a '50s Austin A30. One was black, the other a very dark green. Vinylcote in the beige shade applied to both brought them up to the much lighter colour of the original rear seat with no problems at all and I also used some on a leather seat in my A60 to change that from black to red. It took more coats to do the leather one, but then it was called Vinylcote so I was happy enough that it worked at all.

I was trying some weeks ago to find a current supplier of the stuff with a view to doing some rexine-covered products of the early '60s so this thread is most useful!

Mmmm, H120...........

[Mike Phelan]

Paul & Sean
I'm sure the Keracolor is GRP - I remember seeing the hairy bits on the inside.
I would agree that refinishing it as you would a car is the best bet. 2K paint is not really something you want to do at home without shortening your life; cellulose, even with an aerosol, would be OK. You do need to put a primer with a plasticiser on first, though - "bumper paint" as it is known.

And I've seen the same thing with old pianos with ivory keys. Nice and white if you leave the lid open, but close it for a year and you'll be in for a shock when you open it again

Your elephant probably smoked, Nick.