Like a good number of you, the chrome plating on my eyeball knobs had long since worn off, leaving a fetching brown finish. I had painted them silver - better then nothing but not as original. The knobs could be vapour chrome coated but it’s a bit of a job to do.
Recently I found something on the internet that might be of interest. It’s Molotow Liquid Chrome that comes in a pen. I bought a 1mm pen and tried it - it was impressive and close to a true chrome finish. However, the problem with these paints is that you can’t touch the surface afterwards, it just goes grey. The same thing happens when you try to apply lacquer - the lacquer reacts with the metal particles in the chrome paint and you get grey again.
Then I discovered a lacquer that does not react with the liquid chrome. Its Liquitex Professional High Gloss Finish varnish - an acrylic water based varnish. Note that other water based varnishes I tried do react.
So I painted the knob face only with the Liquid Chrome, and then a day later coated the face only with the Liquitex. A photo is attached, which does not really do it justice - you can see your face in it.
The Liquitex is a flexible varnish so it might wear off if rubbed over a long time, but on a knob face it’s worth a try. I kept the knurled part of the knob silver for this reason - even the original chrome plating would have looked similar IMHO.
So for ?15-20 you can have nicer knobs - if you want to give it a try.
Dave Chapman.