Yamaha DX7 Pt5 - Key repair...fail!

One thing I cant find is a replacement for the top C key. These seem rare. I could try to 3d print one, but it wouldn't look right - it also may not be as strong as it needs to be.
A lot of these projects creates new problems and sometimes I need to get creative when trying to solve these. So the majority of this video is my failed attempt to repair this key.
In the end I try a second approach, where a section of good key - from a broken key is cut out and glued in. This is a little ugly - but it does work and feels ok. This will do until I can find a replacement.
I really love the music of the 70s and the sounds of electric pianos. Though after a decade of musicians giving themselves hernias from lifting their own weight. That era had to end.
In the 1980s keyboards and synths became much more popular due to the lightweight, increased reliability and huge range of possible sounds. Oh did I mention that these had effect built into the synth also?
In 1983 Yamaha released the DX7 this showed off FM synthesis. To be honest I don't understand how FMS works, but I do understand that previous synths used subtractive synthesis. FMS created these brand new glassly bright sounds - similar to the bright brightness of an electric piano.
In 1984 it is estimated that approximately half the top 40 songs that year featured a DX7. The unit was sold unit 1989 and is one of the best selling synthesizers of all time if not the best.
Now when technology is this old, does it still serve a purpose today? It has a 16 note polyphony, after touch, 61 full sized keys - Yes absolutely. It is crazy to think a computer this old would still be useful compared to todays computers.
Though there is a free VST based on the DX7, so dont feel left out if you cant get your hands on a unit, you still can have a play with this synth.
asb2m10.github...
The sounds - well any synth after so much use will be called cheesy. And is did have so much use 80s pop synth music. I think enough time has passed that these sounds are now nostalgic - combined with new recording techniques really gives this synth a new lease of life.
This year was the 40th anniversary of the DX7 release and there was a talk about it at Synth Fest 2023 (Sheffield, UK).
• SFUK 2023 - From DX7 t...

[@tomasdahuabe]

I used a 3d pen to refill some chipped away bits from some ivory keys on a harmonium I'm restoring, you can take the key, fill the broken section with blobs of your desired plastic from the pen, after that remove the blob from the key (if it doesnt bond/weld already if its plastic to plastic) and apply some CA glue between the broken edges and the negative shape left in the blob, glue it together, wait a bit and then very carefully carve away the excess, i used a sharp wood chisel and I didn't even need to sand the section at the end. Hope this helps, kinda felt like a dentist while doing it lol. The result was great
You can find these 3D pens for dirt cheap. I got mine for less than 10 dollars and it's been very useful as a tool. I've also used it to retouch ugly overhang surfaces on FDM 3D prints, Esun PLA+ is my filament of choice.

[@intelligenceservices]

those keys are probably at least to some extent, made with ABS so they may dissolve in acetone, and if so, you can wait a while until your plastic chips *possibly* melt into a gel, at which point you can either paint on that gel or mold the missing plastic into place. it can take a little time for ABS to dissolve if that's indeed the base that the plastic is made with. so basically there's a chance that no glue is needed. just oil free acetone. *If* it's ABS, then at least the parts can be mended together more or less seamlessly by using the same plastic you're putting together, as it's own glue. it's a good idea to put the plastic shreds and acetone in a baby food jar or something glass/polypropelene with a lid so you can test if the plastic melts before the acetone evaporates. if you do stick together two bits of ABS plastic with acetone glue, the surfaces have to be a bit dissolved, i use cotton swabs and repeatedly apply acetone until i feel the plastic start to get a bit slippery or saturated with it.

[@lundsweden]

I think the repair looks ok... who knows, maybe you'll find a proper replacement in the future. I'm thinking (some) Korg keyboards might have the same action. I've opened up a Z1, it had those stainless key contacts. So maybe Korg's better keyboards have the same key switches/ and maybe even the same keys. I'm thinking Trinity, maybe M1, T1, T3 etc. Yamaha after all had a stake in Korg around that era.

[@SubbParProductions]

But what is the secret to getting all the Key Springs back in tidy? I never want to do that again...

[@deancoyle]

Remove the contact PCB and it's a lot easier. You can't damage the contacts also. But I do agree it does take some time whichever way you do it.