Hello Mr Smith,

this data could be used as base for 3D printing, but it would need to be modified and scaled up, because printing a working 1:1 Curta woun't work.

MrSmith wrote:

Dumb question, but is this used for 3D printing a Curta Calculator? I've seen that on youtube: https://www.youtube.com/watch?v=mG4A3R4imnc

The models I used for 3d printing it are public on onshape
The actual stl files, tools, parts, build manual are up on thingiverse

Sebastian, I found a few inconsistencies in the engineering drawings when modeling that I had to correct for a working Curta. Did you notice any?

Sebastian wrote:

Hello Mr Smith, this data could be used as base for 3D printing, but it would need to be modified and scaled up, because printing a working 1:1 Curta woun't work.

Can I ask why you couldn't print a 1:1 scale Curta?

thanks

MrSmith wrote:

Sebastian wrote: Hello Mr Smith, this data could be used as base for 3D printing, but it would need to be modified and scaled up, because printing a working 1:1 Curta woun't work. Can I ask why you couldn't print a 1:1 scale Curta? thanks

I ran a few tests at 1:1 using shapeways. The parts I ordered came out way too weak to function. In fact, I had to work around some strength issues even at 3:1 scale to get a functional device.

I had to thicken the spider spring and the spring that pops the step drum between addition and subtraction. I also printed all of the pins and the support columns horizontally. The printer layers plastic up so the z-axis is the weakest. Printing those horizontally allowed them to withstand more stress along their length.

A 1:1 Curta would probably mostly require the same materials the Curta was originally produced with. There are a few exceptions, but mostly on the external non-mechanical parts. The interior mechanical parts are closer to watchmaking work than normal machining /manufacturing.

makes perfect sense, thank you

what amazing work!
Congrats and thanks for sharing it!

Hi mwu,

Are the 1:1 part files available to download? I see the 3:1 parts are. I also see the 1:1 available to view but can they be saved. Thank you

Regards,
Alex

Great work by Marcus.