{"id":2484,"date":"2016-07-30T14:41:29","date_gmt":"2016-07-30T13:41:29","guid":{"rendered":"http:\/\/www.untergeek.de\/?p=2484"},"modified":"2016-09-04T00:27:48","modified_gmt":"2016-09-03T23:27:48","slug":"whitening-jennys-smile-bleaching-the-old-synth-keys","status":"publish","type":"post","link":"https:\/\/www.untergeek.de\/de\/2016\/07\/whitening-jennys-smile-bleaching-the-old-synth-keys\/","title":{"rendered":"Whitening Jenny’s smile: Bleaching old synth keys"},"content":{"rendered":"
<\/div>

Jenny – my old 70s monosynth<\/a> – is a beauty, and I love her knobby face. Her smile, though, has yellowed over the decades. So to make Jenny even more attractive, I decided to try and bleach the keys with hydrogen peroxide.<\/p>\n

TL;DR: Effect has been minimal, so it’s probably not worth it. But it was fun. If you try it, make the Retrobright bleaching gel, don’t use a hydrogen peroxide bath. And have a good UV <\/em>source.<\/em> <\/strong><\/p>\n

\"Old<\/a>

Jenny’s keyboard compared to a key from a mid-80s Roland JX8P synth<\/p><\/div>\n

In School, I used to hate chemistry. Did I mention that I used to hate chemistry? Okay, I did (when successfully reviving Jenny’s keyboard contact springs by cooking them<\/a>)<\/p>\n

So here’s what I did.<\/p>\n

<\/p>\n

It is quite easy to take Jenny’s keyboard apart – just remove the six housing screws, and the two screws holding the keyboard plate from below. Then take out the keys by removing the key springs.<\/p>\n

\"img_4568\"<\/a><\/p>\n

The 25 white keys fit just about right into two transparent Samla boxes from Ikea.<\/p>\n

\"Keys<\/a><\/p>\n

Now, the chemical agent. I used a 12-percent hydrogen peroxide solution. 10 litres of it cost me about 20 Euros, and I used three litres for this experiment.<\/p>\n

\"A<\/a><\/p>\n

Don’t want to know into what kinds of database I have landed by buying this. There was the case of an alleged terrorist bomber who was arrested after trying to obtain three litres of hydrogen peroxide under an assumed name. I bought ten, albeit in a weaker concentration. Well, you can just order it via Amazon, so I guess it’s not really that relevant.<\/p>\n

\"Hydrogen<\/a><\/p>\n

As mentioned before, it took about 1.5 litres for each container to have all the keys covered. I had not expected that they would swim though. JEN keys float – you’ll have to put a weight on top of them if you want to submerge them properly.<\/strong><\/p>\n

Then, the containers went into the sunlight, to a spot normally reserved to grow our tomatoes.<\/p>\n

\"Containers<\/a>

Warning sign reads: „Bleach. Don’t touch. Not really dangerous but unpleasant.“<\/p><\/div>\n

This is what should happen: Ultraviolet radiation splits the H2<\/sub>O2<\/sub> into water and oxygen radicals, which then oxidize the yellowing molecules. So the containers went to the window sill, well protected from the hands of curious little children, and well secured.<\/p>\n

I also made a simple reflector from aluminium foil to catch all UV rays. Unfortunately, the 2016 summer is a mixed bag in Germany. If you can, pick a sunny day\/area.<\/p>\n

\"Cloudy<\/a><\/p>\n

In case it rains, it is good to have the lids for the Ikea boxes ready.<\/p>\n

\"Keys<\/a><\/p>\n

After about 20 hours in the bleach – you can see that the weight to keep the keys under clearly gets oxidised, the steel is no longer stainless. The keys? Less so. Bad luck with the weather. But if – if! – the sun comes out, you can see oxygen bubbles forming in the water.<\/p>\n

Evaluation: Little success with the 12-percent solution<\/h2>\n

Unfortunately, even three mildly sunny day did not yield satisfying results. So I reassembled Jenny, feeling beaten. Breaking a contact in the process; fortunately, it could easily be fixed.<\/p>\n

\"img_4586\"<\/a><\/p>\n

The keys are still notably yellowed.<\/p>\n

\"img_4588\"<\/p>\n

A friend asks me to consider whether the keys may have been slightly yellow in the first place – organ keys tend to have that vintage ivory tone, maybe Jenny’s parents thought this would suit her as well – and although this is a possibility, I concluded that my experiment had failed, and went back to research.<\/p>\n

Which made me stumble onto this site (in German).<\/a> It takes a theoretical as well as an experimental approach to the problem of bleaching old, yellowed plastics, and thus seems to be a good lead for another attempt. Main takeaways:<\/p>\n