3D printed Cherry MX keycap

User avatar
kekstee

3D printed Cherry MX keycap

Unread post by kekstee » 14 Dec 2012, 15:28

If you asked me a week ago whether (consumer) 3D printed keycaps would work, I would have said: probably not. Now that I got to try it I have to say: it's shit but kinda works for novelty items.

Image

I'll try to elaborate a bit and post my source files, so anyone can try it if he has access to a printer.
First, the machine used was an Ultimaker. It was only sightly modified with a heated bed and optimized feeder, but I guess thats not really important for this object.

Maximum z-resolution is 0.1 mm. On the x and y axis you can't really tell, but it's probably equal at best and definitely more in this case. No real measurements exist on this particular machine though.

Printing this key took 20 minutes, at a layer height of 0.1 mm. The inside is hollow and filled with support structure for printing. The filed result you see in the picture weights 1.5g.

PLA plastic was used since it's fairly easy to handle and shows no contraction during cooling.

The key

I went for a key base of 18x18mm² and a flat top of 12x15mm². Corners were rounded with r=2mm. I had no means for decent measurement, so everything is kinda eyeballed.

The connector pins were assumed to have a width of 1.0mm on the vertical section and 1.1mm horizontal, at an overall width of 4.0mm. Measurements with some digital calipers that I did on the stems afterwards showed me 1.1 and 1.25mm instead.
I added 0.4 mm to each of those initial numbers to make room for the uneven surface, bad print quality and the lack of decent measurement (and ended up scaling the whole key by 1.02, including this connector). After some filing inside the connector and taking away material on the outside of the pin (especially the lowest layer turned out ugly) it actually fit on the keyboard better than I ever expected. It doesn't require excessive force and doesn't come off by accident. Keypress itself feels smooth now. Of course it isn't perfectly aligned.

Image

The inside has 4mm of air around the connector to allow for key travel. Although the 50% support structure which gets generated by Cura breaks away quite easy, it still leaves an ugly surface on the inside top and the bottom of the connector, which was set to start 0.75mm above the skirt of the keycap. Infill of the solid parts was set at 100%.

Some more shots of the keycap in use and the alignment achieved: 1 2 3

The surface

I'll just show you this picture. On the left are the results from first contact with the printer. Layer height was 0.2 mm to get done faster. Obviously it's horrible and the connector was far too small. I actually butchered one with a hot knife to make it fit, but I definitely needed another shot.
So the two keys on the right come from an optimized design with more space inside the key and larger connector dimensions to account for the lack of accuracy. This time a decent print with 0.1 mm layer height.

Image

You can see both keys raw from the printer and filed to make the surface a bit nicer to touch and look at. Of course there are limits, I guess gently sandblasting it would be the only way to achieve a decent surface on details.

Also note that the whole key was scaled by 1.02, both because I figured my measurement was probably off and to allow for filing the surface without ending up with a small key.

The horizontal lines you can see on every keycap are faulty layers. I'm not entirely sure if it's a problem with the machine's z-axis or the print settings used for code generation. Remarkably they are very similar on all keys. Other objects printed with the machine sometimes end up having them, sometimes they don't or at least they are not always as prominent.

Oh and regarding the broken one: don't print it on a raft, too much reinforcement for the support structure inside. I broke it with a screwdriver while cleaning the inside, and the bottom of the pin is a really weak point with this design.

Software & Sources

I tried to keep everything fairly modular, models on top and geometry settings for different key rows should be easily modifiable. Guess you wouldn't want a key like this anywhere else though.
It's all open source software, so you can easily play with the existing model inside OpenSCAD. If you start from scratch you probably want to use a professional CAD application if you happen to have one available to you.
IRC

I got dragged into #gh last night for a little Q&A after posting a picture, and I think I covered about everything discussed there.
One thing stuck out from the logs after I went to sleep though:
03:14 < eckse_> it would be even cooler if the skull were hollow
03:14 < eckse_> an led underneath would be awesome
Well, there happens to be an LED beneath this key on the Poker. Although it is only lit when the ~ key is changed to ESC by Fn, so I didn't really think of it.
I guess I could poke out the eyes from an earlier attempt and see if it even works without a light conducting material from the LED to the eyes.

TODO
  • post sources -- github
  • poke out eyes
Last edited by kekstee on 26 Apr 2018, 03:45, edited 3 times in total.

User avatar
webwit
Wild Duck

Unread post by webwit » 14 Dec 2012, 15:37

Very nice. Just give it some years, and we'll all be printing our own cases and caps. 3D print shop is going to open in my town next month, maybe I'll give it a try.

User avatar
7bit

Unread post by 7bit » 14 Dec 2012, 16:09

This skull key cap looks really scary!
webwit wrote:Very nice. Just give it some years, and we'll all be printing our own cases and caps. 3D print shop is going to open in my town next month, maybe I'll give it a try.
Please let them make a keyboard in the form of a duck!
Image

e30andrew

Unread post by e30andrew » 14 Dec 2012, 18:41

Awesome job so far! Im curious to know what grower you are using?

The growers i am familiar with can print layers of 25 microns, which is .025mm's thick, and would be more than capable of growing a perfectly smooth key out of a nice hard resin.

would you be willing to post your file? Id love to have a go at it!

User avatar
kekstee

Unread post by kekstee » 15 Dec 2012, 00:25

It was done using the Ultimaker. Of course there exist more capable professional solutions and other techniques.

Just added my source files to the post. Had to tidy them up a bit first.

User avatar
Daniel

Unread post by Daniel » 15 Dec 2012, 13:44

Thank you for sharing this! I think this will be helpful for anyone planning sth. similar. Especially the used software section is helpful.

IvanIvanovich

Unread post by IvanIvanovich » 15 Dec 2012, 17:41

Interesting. They remind me of Día de los Muertos items. I prefer them much more than those Clacks.

User avatar
suka
frobiac

Unread post by suka » 20 Dec 2012, 14:58

@kekstee: Thanks for the inspiration, always meant to try out openscad but never got around to actually install it - until now! Much better than blender for the technical part of my designs (e.g. mounting frame for the MX ), wish I'd tried it earlier.
IMAGE00043.jpg
Bad quality camera image, will upgrade later
IMAGE00043.jpg (91.12 KiB) Viewed 21887 times
Hope you don't mind I had to try out your design - looks pretty slick already, but I scaled it too big so it no wiggles on the stem.
7bit wrote: Please let them make a keyboard in the form of a duck!
Image
Got a 3D-model of one? :D With all the CC hype this might be a genuine goldmine :mrgreen:

User avatar
kbdfr
The Tiproman

Unread post by kbdfr » 20 Dec 2012, 15:52

Aren't you guys tired of those skulls?
Spoiler:
Image

woody
Count Troller

Unread post by woody » 20 Dec 2012, 22:56

Back to skull.

User avatar
kekstee

Unread post by kekstee » 21 Dec 2012, 17:58

@suka: nice :D Glad someone gets to play around with it.

The surface looks good as well, what kind of printer did you use for this?
I really hope more accurate machines will become affordable one day.

Unrelated 3D printing nonsense: http://www.instructables.com/id/3D-Printed-Record/

User avatar
damorgue

Unread post by damorgue » 21 Dec 2012, 19:35

Always nice with more people with access to 3D printers around here. Join the tribe

lkong

Unread post by lkong » 01 Jul 2013, 05:53

hey kekstee
Thank you for your work. I forked you on github and did a little change on it.
https://github.com/lkong/3dprint
I will try to print it in a local fablab sometime soon.
Attachments
example.jpg
example.jpg (16.26 KiB) Viewed 19983 times

lkong

Unread post by lkong » 16 Aug 2013, 00:07

I modified mine and printed from shapeways with stainless steel.
Attachments
DSC00218.jpg
DSC00218.jpg (195.88 KiB) Viewed 19334 times
DSC00215.jpg
DSC00215.jpg (166.22 KiB) Viewed 19334 times

User avatar
Muirium
µ

Unread post by Muirium » 16 Aug 2013, 01:12

Yikes! That's nasty done nice. How much would it cost for a stainless cap with, say, a letter on it instead of a skull? This is the future right here, I hope…

lkong

Unread post by lkong » 17 Aug 2013, 21:03

Muirium wrote:Yikes! That's nasty done nice. How much would it cost for a stainless cap with, say, a letter on it instead of a skull? This is the future right here, I hope…
it's charged by volume. mine costed 21.

User avatar
Muirium
µ

Unread post by Muirium » 17 Aug 2013, 23:03

Yeah, still the future then. But once it's down to a coin per cap, things should suddenly get busy. Same for all technologies. There's a moment when things take off.

lkong

Unread post by lkong » 18 Aug 2013, 21:47

Muirium wrote:Yeah, still the future then. But once it's down to a coin per cap, things should suddenly get busy. Same for all technologies. There's a moment when things take off.
Yes
The price can be easily brought down by switching to less expensive material.
The same model will cost less than 5 dollars to be print in alumide.

battletux

Unread post by battletux » 07 Sep 2013, 08:31

If you're printing in ABS then you could try acetone vapor to smooth the cap to make it look nicer: http://hackaday.com/2013/03/23/smoothin ... one-vapor/

User avatar
Game Theory
Mr. Despair

Unread post by Game Theory » 07 Sep 2013, 16:08

lkong wrote: Yes
The price can be easily brought down by switching to less expensive material.
The same model will cost less than 5 dollars to be print in alumide.
Was your print matte or glossy. Thinking on having one printed at Shapeways.

User avatar
Game Theory
Mr. Despair

Unread post by Game Theory » 07 Sep 2013, 16:09

battletux wrote:If you're printing in ABS then you could try acetone vapor to smooth the cap to make it look nicer: http://hackaday.com/2013/03/23/smoothin ... one-vapor/
Note all the warning in the comments at that link :o becareful!

User avatar
csmith

Unread post by csmith » 27 Mar 2016, 05:59

Nice!

There's a successful Kickstarter for a new 3D printer powered by your smartphone or tablet (Android, iOS or Windows). It's going to be $100 and claims a resolution of 32 microns. It isn't a large device, but is more than large enough to do a bunch of keycaps. Assuming it all happens, the tooling will be cheap enough for us all to have some fun with this. They said the resin they use will be competitive with other 3D printing technology, so the cost of doing a whole set of caps will still be insane, but it should be good for doing one of a kind Esc keys and stuff like that. Hopefully the resin will come down in price over time.

https://www.kickstarter.com/projects/ol ... 3d-printer

Note: I have nothing to do with this project, and have not backed it, but may do.

User avatar
vvp

Unread post by vvp » 27 Mar 2016, 15:43

I have a 3d printed keyboad case.

But I tried a keycap too:
bot.jpg
bot.jpg (48.88 KiB) Viewed 6796 times
top.jpg
top.jpg (31.23 KiB) Viewed 6796 times
And here is the model of the keycap. It is a FreeCAD design file. License is public domain. I do not claim it is good for anything. Anyway the thick keycap stem is quite easily printable and works OK once you force it on a cherry mx switch stem. The first time it is hard. Then it is OK. Printed on a simple FFF RepRap with ABS with Ø 0.5 mm nozzle, 0.2 mm layer height. And painted with acetone; I'm lazy to do full acetone vapour bath.

User avatar
csmith

Unread post by csmith » 27 Mar 2016, 16:09

Hey vvp, that case is sweet.

I'm really interested in 3D printing, but it's still quite expensive, even once you have the tools. Any help getting a handle on realistic running costs would be helpful. How much do you reckon your case cost in materials?

User avatar
vvp

Unread post by vvp » 27 Mar 2016, 17:48

2 kg of good quality ABS or PLA is about 50 €. There is some cheap filament too but it is probably not worth it. Well, people claim that but I do not know for sure since I never bought any cheap filament.

The K80CS case is about 8 € in material. There is some energy cost too but I that is negligible ... in the range of about 3 kWh. Of course, there is a price of the 3d printer itself. A do-it-yourself RepRap printers are in the range of 500 - 1200 €. But making a 3dPrinter yourself is a significant undertaking. A bigger project than making your own keyboard.

User avatar
csmith

Unread post by csmith » 29 Mar 2016, 15:01

Thanks vvp. That's really helpful information. I thought it'd be much more expensive than that, more like 100 Euros. Katy is badass - really nice job there. My plan is far less ambitious. I just want to make a case for replacing the one on an OEM keyboard.

Thanks again.

User avatar
csmith

Unread post by csmith » 30 Mar 2016, 23:40

There's a company here in the UK that will print keycaps for about a dollar. I just created a new thread about them:

other-external-f66/custom-keys-printed- ... 13425.html

Post Reply

Return to “Workshop”