How to restore discoloured fader caps?

[BelfastGooner]

I just bought a Yamaha O2R 24 (with 2 adat cards and meter bridge for a ridiculously low price) but the 16 white fader caps have all discoloured over time. I was just wondering if theres any safe way to restore these to their original colour, or as near as possible? I saw on one forum, someone was recommending using the "Retrobrite" method of hydrogen peroxide and UV light. Others, however, say this will turn the plastic to dust and not to use it.

Any help or suggestions appreciated.

[Mike Stranks]

Bit of a sideways approach, but often on eBay you'll find people selling-off various knobs and fader-caps from mixers that they've disassembled...

... just search 'Mixers' in 'Pro Audio Gear'.

[Martin Walker]

Yes, I've seen suggestions of hydrogen peroxide, although I'd be careful with that one.

The gentlest way to try at first is with warm soapy water and an old toothbrush before you investigate fiercer approaches.

[Sam Spoons]

In the sailing world we use oxalic acid solution to remove rust stains from sailcloth and GRP, not sure whether it would work with whatever plastic used to make fader caps though. That said if you could source a few spares off ebay they will likely be similarly discoloured so you could experiment with different approaches.

I'd also start with soapy water and a toothbrush though (as MW says).

[James Perrett]

Try putting them in the washing machine. This worked well to restore the knobs on my A&H desk to their full glory. I put them in a washing bag first though and I think I used a fairly gentle setting.

[Wonks]

You could just get a can of spray paint and spray them after cleaning them in soapy water, if that initial cleaning doesn't work.

[OneWorld]

I just bought a Yamaha O2R 24 (with 2 adat cards and meter bridge for a ridiculously low price) but the 16 white fader caps have all discoloured over time. I was just wondering if theres any safe way to restore these to their original colour, or as near as possible? I saw on one forum, someone was recommending using the "Retrobrite" method of hydrogen peroxide and UV light. Others, however, say this will turn the plastic to dust and not to use it.

Any help or suggestions appreciated.

Yep you have to be careful what you use for cleaning. I thought meths was quite ‘benign’ and so I thought I would use it to clean my Virus TI and ended up wiping off the text for the controls

[orange]

I've used hydrogen peroxide on yellowed fader caps - took about an hour. I didn't use UV but left them to soak out in the garden on a sunny day.

It worked perfectly and came out totally white. No damage to the black printed line.

I also used it on some other coloured fader caps and also helped them look much better too.

They didn't melt/turn brittle/disolve/turn to dust

That was about a year ago and they still look white and haven't re-yellowed.

[Wonks]

I've used hydrogen peroxide on yellowed fader caps - took about an hour. I didn't use UV but left them to soak out in the garden on a sunny day.

So you did use UV.

[orange]

I've used hydrogen peroxide on yellowed fader caps - took about an hour. I didn't use UV but left them to soak out in the garden on a sunny day.

So you did use UV.

hence why I pointed out it was a sunny day

[BelfastGooner]

I've used hydrogen peroxide on yellowed fader caps - took about an hour. I didn't use UV but left them to soak out in the garden on a sunny day.

It worked perfectly and came out totally white. No damage to the black printed line.

I also used it on some other coloured fader caps and also helped them look much better too.

They didn't melt/turn brittle/disolve/turn to dust

That was about a year ago and they still look white and haven't re-yellowed.

So did you use neat hydrogen peroxide, or did you dilute it?

[BelfastGooner]

I've used hydrogen peroxide on yellowed fader caps - took about an hour. I didn't use UV but left them to soak out in the garden on a sunny day.

So you did use UV.

I have a UV light which came with a UV activated screen protector. It has 2 rows of 10 tiny UV leds. I'm just wondering if this would be safer to use than a whole day's worth of sunshine.