Printing keys of a MIDI keyboard

[t_w]

Hello!

I want to replace the keys of a MIDI keyboard. The keys are going to have 12 different colors. This involves at least

• 3D scanning/modelling,
• 3D printing/CNC milling and
• painting.

The keys need to be replaced instead of just getting painted because of this desired layout, repeated on the whole keyboard:

ASCII:                       Unicode:
|  |#| |#| |#| |#| |#| |#|   │  ▐█▌ ▐█▌ ▐█▌ ▐█▌ ▐█▌ ▐█▌
|  |#| |#| |#| |#| |#| |#|   │  ▐█▌ ▐█▌ ▐█▌ ▐█▌ ▐█▌ ▐█▌
|  |#| |#| |#| |#| |#| |#|   │  ▐█▌ ▐█▌ ▐█▌ ▐█▌ ▐█▌ ▐█▌
|  |#| |#| |#| |#| |#| |#|   │  ▐█▌ ▐█▌ ▐█▌ ▐█▌ ▐█▌ ▐█▌
|   T   T   T   T   T   T    │   │   │   │   │   │   │
|   |   |   |   |   |   |    │   │   │   │   │   │   │
|___|___|___|___|___|___|    └───┴───┴───┴───┴───┴───┘

I want it to be as cheap as possible, yet I need stable keys, of course (the keyboard costs about 150 $). If you need to get an idea of how the keys look like inside, take a look at this page or this video at 2:18 min.

1. I'm not into 3D scanning. I only took a look into Blender with a few tutorial pages. I tried 3D scanning with VisualSFM and insight3d, but, unfortunately, wasn't able to achieve anything yet. I realized, I would possibly be able to use a fiverr.com service for that. The 3D models also need to be edited/combined to get keys that look like this. Do you know how to get 3D models of my keyboard keys (scanning at least 2 original types)? Are there affordable professional services for 3D scanning, or those from private persons? (I'm located in Germany.)
2. Can you tell me, what creation techniques are the best? Is CNC milling cheaper and more stable? What material should be used for maximum stability and longevity at a moderate price? What postprocessing is required on 3D printed keys?
3. What's the best and cheapest way to get colored keys? 3D printing/CNC milling in the desired colors (might not be possible), or spray-painting them?

I hope you can help me with at least some aspects of my project! Thanks!

[cobnut]

Hi t_w, is this for a one-off or for a production run? If it's for a one-off you're almost certainly going to find anything other than 3D printing prohibitively expensive, although 3D printing (unless very high quality) is more likely to be the least long-lasting and lowest quality, so it's a trade-off. Either way, you'll probably want to 3D print the initial versions to check their dimensions, etc before going to any other service. If the keys are anything like the sort I've seen over the years, it should be fairly simple to produce a 3D model and Blender is really using a sledgehammer to crack a nut. With simple planes like this 123D Design would be fine, or pretty much any of the free simple modellers, though of course "simple" is defined by experience.

Colour shouldn't be a problem for any process, although for 3D printing it could be a moderate pain changing the filament so often, but that depends upon the printer.

[t_w]

Thanks for your answer. I'm going to do this only once with this keyboard.

Do you mean it could well be that 3D-printed keys don't last very long? Then I can throw aboard the idea of using 3D-printed keys for years to come.

And if CNC milling is not affordable, there might be no new keys at all! Unfortunately, it's hard to find services for private persons. I just couldn't get an idea of the price for CNC milling.

I didn't realize more simple 3D modeling software like 123D Design. I'll take a look into it.

[cobnut]

Thanks for your answer. I'm going to do this only once with this keyboard.

Do you mean it could well be that 3D-printed keys don't last very long? Then I can throw aboard the idea of using 3D-printed keys for years to come.

And if CNC milling is not affordable, there might be no new keys at all! Unfortunately, it's hard to find services for private persons. I just couldn't get an idea of the price for CNC milling.

I didn't realize more simple 3D modeling software like 123D Design. I'll take a look into it.

If it's a one-off, I'm pretty sure you'll find all professional milling/casting/moulding solutions will be very expensive. I could be wrong, especially if you can find a local person who's happy to do it cheap, but these services tend to require substantial setup of the gear and their time is money. Have a look for a local company and go and see them, I'm sure they'll be happy to look at the job and quote for it, then you'll know.

How long will a 3D print last? That's impossible to say as it depends upon the material you use, the extent of the usage, any treatments you apply after printing, and so on. However, bear in mind that one of the beauties of 3D printing is that if you print a part and it wears out, you can just print another one exactly the same.

[t_w]

What's your attitude with those companies that seem to be only interacting with companies? I hardly dare to try asking them about constructing something for me. Isn't there something law-related that means they can't interact with me for a business job?

[curious aardvark]

the keys look pretty simple.
You need openscad and a set of digital calipers, just measure and replicate.
Easier than it sounds :-)

3d printed pla keys will be pretty hard wearing and available in lots of colours.
Can't see any real reason they'd wear out any faster than the original keys.

although 3D printing (unless very high quality) is more likely to be the least long-lasting and lowest quality,

That's just not true.
Depending on the material used they could actually last longer than the original keys.
Unless you're building a muppaphone:
https://www.youtube.com/watch?v=JaL6s4eNNBg

What you actually need to do is find a 3dhubs person near to you.
https://www.3dhubs.com/

Ask them and see if they could produce the stl file as well as print the keys.

But something like that would be pretty straight forward to duplicate in openscad.

[t_w]

the keys look pretty simple. You need openscad and a set of digital calipers, just measure and replicate. Easier than it sounds :-)

I just got digital calipers. Thought I would need to measure instead of 3D scan.

3d printed pla keys will be pretty hard wearing and available in lots of colours. Can't see any real reason they'd wear out any faster than the original keys. Depending on the material used they could actually last longer than the original keys.

Thank you very much! You built me up! I think I can have more confidence in 3D printed objects, then.

OpenSCAD

I find it rather complicated, although I'm familiar with some programming languages. Seems like learning that is a project of it's own. Maybe I would have more luck with 123D Design or a similar program. I took a look into it. I couldn't figure out how to work exactly, though (e.g., rotating once, then rotating later again resulting in a specific angle).