July 22, 2023
Description
Copyright © Herr Brain 2023.
This source describes Open Hardware and is licensed under the CERN-OHL-P v2.
You may redistribute and modify this documentation and make products using it under the terms of the CERN-OHL-P v2 (https:/cern.ch/cern-ohl). This documentation is distributed WITHOUT ANY EXPRESS OR IMPLIED WARRANTY, INCLUDING OF MERCHANTABILITY, SATISFACTORY QUALITY AND FITNESS FOR A PARTICULAR PURPOSE. Please see the CERN-OHL-P v2 for applicable conditions.
The license notice at the bottom of this page is incorrect. However, until Prusa fixes the license menu to include either an appropriate OSHW license or adds a “custom” option, my only viable option is to select “standard digital file license”. Unfortunately, this also prevents the easy creation of remixes. Meanwhile, I would like to strongly encourage everyone to read or at least skim through the CERN OHL (it's short), and to encourage Prusa to add support for it on this site.
CERN OHL is a open source license tailored specifically for hardware designs. There are a number of protections that software and CC licenses do not cover. Roughly speaking, the -P (permissive) variant is analogous to the BSD or MIT licenses for software, or loosely comparable to CC-BY. You are free to remix this design so long as you leave the license notice intact. While this license is arguably overkill for such a small project, I wanted to release it as a proof of concept and demonstrate the correct way to license a project under OHL. I will likely do this for all of my future designs.
✖ | Sharing without ATTRIBUTION
✔ | Remix Culture allowed
✔ | Commercial Use
✔ | Free Cultural Works
✔ | Meets Open Definition
ℹ | Keep original license intact
None of the existing options are really appropriate for hardware designs. The functional aspects of a design like this one are covered by patent, not copyright law. Unlike copyrights, patents are never “automatic”. In practice, this makes it possible for someone to take your design, claim it as their own, patent it, and then sue you for royalties. OHL has a mechanism to protect against such abuse. Other notable benefits of OHL include the notion of “available components” that allow designs to utilize proprietary components, assuming that the interfaces to those components are fully specified. For example, Prusa could release the motion system for the XL without having to disclose very detail about the Nextruder design.
If you are going to support open source hardware, please do it right!
I've actually been wanting a decent paper towel dispenser for awhile. As it turns out, I got a cold this week, so I actually had time to design one. Of course, being the DIN-obsessed individual I am, I had to make it DIN-mounted. I used a new clip design based loosely on DUFF v3, but with an added “trigger” that makes it possible to detach by hand. I've also added a small grease port. While not strictly necessary, I found that adding a little PTFE lube did make the print in place mechanism slightly easier to turn.
This project turned out to be an excellent opportunity to play around with B-splines, and I will likely incorporate them into more of my designs in the future.
Print settings: check the 3mf. I strongly recommend PETG. PLA will be too brittle.
License:
Standard Digital File License
herr_brain
