Is mpCNC open source?


I’m a little concerned that the mpCNC is not open source.

The parts are downloaded with a CC license… attribution, non commercial, share alike… I can give away the files. I can modifiy the files, but I can’t sell the files… or the parts?

If someone in my city wanted a mpCNC and I offered to print the parts for the cost of the PLA, am I violating the license?

Why not fully open source?

What’s the intention here?

I’m excited about my build, but I strongly believe in open source and I want to support open source.

Let me hear your side. Why not be non-commercial?

You’re not in Mexico are you?

“Why not be non-commercial?”

Hmm… I’m not necessarily opposed. Let me get my thoughts out of my head here…

  • This is a cool machine and I want to see it get stupid popular. Thank you! :D
  • I believe that open source encourages useful feedback and wide usage.
  • Non commercial allows people to download, print, build, etc.
  • They can't sell your CAD files, or use them for commercial work.
  • Does Non Commercial prevent other people from selling the machine?
    • I... don't think so? They can't sell your CAD files, but can sell what they print from them, I believe.
      • I think this is good. It spreads the design, can create more work for you (support, etc), and helps people get extra income. Everyone wins.
  • Does Non Commercial prevent people from using a mpCNC to do paid work?
    • I don't think so. Again, the CAD files are licensed, but the physical machine is not.
      • I think this is good. If your machine can help people earn some extra income, hoory, you've made the world a better place. Everyone wins.
  • So, really, the NC license just prevents someone else from selling your CAD files. It doesn't prevent commercial usages from the machine, as far as I can tell.
If I'm right about the license being applied to the CAD files but not to the physical machine, I think that's just fine. If the intent is to restrict what people do with the machine, I don't think that works, and I'd be opposed to it on moral grounds.

Your thoughts on my thoughts?

And thanks. :smiley:


No, I’m not in Mexico. Uhm… Why does that matter?

Soy un gringo, pero hablo un poco, si solo hablar con mis vecinos. Si, hablo que un nino estupidio. Yo se. :smiley:

You can’t sell my files or my parts. You can 100% do what ever you want with things you produce with it. Yes you can sell your products.

Correct. All parts based off of mine need to keep the exact same license and make sure there is attribution as well.


Yes, no money can exchange hands. Feel free to ask me if you want to print a set or two for a some friends. Beyond that we need to have a longer discussion.


What part about me sharing my hard work is bothering you?


I don’t catch your meaning behind this.

Not true. You can use a non commercial machine to make things that take your hard work that you sell, you just can’t sell my hard work.


This is all wrong. This is exactly what non commercial means, you can not sell my work, files or physical parts. Again you can sell what you create using it.


Yes the physical machine is protected under license, you can not put together and sell my machines either, only what you make with it.


Covered this a few times already I think you get it.


You are kind of right but keep wording it very incorrectly.

Think of it this way, if you did not design it, you should not sell it. If you want to sell it, 80% of the work is actually supporting it so be prepared to step up.


The world is not black and white. There are levels of open source.

You still have not given a reason that you are so passionate about this being “fully” open source, or did you just misunderstand what noncommercial was?

Here’s how I would explain it:

Ryan has this machine and selling the parts and hardware kits pays for the development of the machine. He wants to support the machine and so he answers every question in the forums (almost). He doesn’t want his stl files to create parts that will be sold by others. He doesn’t want to support those other people’s profits and it just generally makes him uncomfortable.

None of that answers your question, but it is how he enforces his copyright. And it is his copyright.

Now, the good news is:

He encourages people to print their own parts or print them for a friend, or sell used parts if you change your mind.

His software is truely open source. The configurations used on the machines, the Marlin versions they are made for, etc. They are all on public github. He has even contributed back to Marlin source code. That’s more than many printer manufacturers.

He supports the forums and there’s a ton of help here.

He supported me when I wrote sandify and v1pi, which are both MIT projects. Not monetarily, but with site resources and a lot of advice and testing.

He offers a complete BOM, and works a TON to make sure to design for parts that are common, reprap style parts. Available all over the world.

The result is that you can download the stls, print them yourself, buy a few pieces of common hardware (which he lists), flash with his firmware, use his instructions, ask for help on these forums and use v1pi to control it. All without giving Ryan a cent (and plenty do that).

At the end of the day, I’m a strong supporter of open source. I am also a strong supporter of Ryan and that’s why I choose to buy hardware from him, print my own parts and eventually, I went overboard and started spending more time here than on reddit.

TL;DR open source software, really close to open source hardware, but not quite. Super nice guy though.


You give me too much credit, but otherwise a very eloquent explanation.

The deep down honest truth is I feel as if I went non commercial, I do not think I could put in the time that I currently do. Profit margins are tiny, lose to much of it and I would be in trouble.

I think a few fully open source hardware companies are protected by the fact that they use hardware or parts that you can not get or make yourself. I really really go out of my way not to use uncommon parts, precision cut and bent metal, do my best to make all hardware fit if not perfect it can still happen. Designed for other hardware, not just one company where possible. I want you to be able to make one by yourself, I don’t have to have your money. I do not feel that other companies have a claim to my/our development time and energy.

To just put a bow on this of all the companies that have asked to be an authorized partner backed out. My requirements…devote resources to supporting it (preferably in the forums), and I want a single digit percentage licensing fee (less than the industry standard). No one has agreed.

The one company that made cut MP3DP parts, offered me $2 per set. I agreed, I got $6 in total and caught them selling them without giving me the $2 they offered. The excuse…“I wasn’t selling enough”

The generosity, support, and amazing people I have met (virtually and IRL) that this machine has created is the best thing I have ever been involved with. I am very protective of that. I have been in other forums and it is a nasty experience. This is how I think I can best protect that. It is not really a money thing, it is something I am scared to lose, and it takes some money to do that.


I think that the inventor of something has the right to make a living out of it.

He created the machine, the documentation and basically did everything, taking on his own free time, energy and money. He could just have build this machine for himself and not sharing it outside, it would have been way less trouble and much less work.

The stl files are available for free, isn’t it enough? Anyone can download them and print his own machine. And let’s be honest with ourselves, if someone is printing parts for one or two friends for a few bucks, well there is no way it will be noticed, ever, even if it is not allowed. It will however be noticed if someone does it in a much bigger scale, which is, I suppose, what Ryan tries to avoid.

I’m not actually sure that going full open source will make a difference regarding protection, since it is really not that difficult to redesign entirely the thing and make it your own to sell it, but it is still a bit more protection than nothing.

Anyways, I think Ryan deserves to make a decent living out of his invention, so I totally support his decision.


I guess I should be ashamed to admit that I had the parts printed through 3d hubs because it was cheaper and I could choose the colors I wanted, as I didn’t have a 3d printer at the time. The guy that printed the parts, however, didn’t charge any more than would’ve for any other print job. I did buy my hardware and board through here though. Board prices were so much more reasonable than even buying direct through Ultimaker.

It was cheaper through 3D hubs? Last I checked it was 3x, and you could not get the thick walls and “dense” infill. I will have to look again.

He should not have printed them, license prohibits that. 3D hubs used to be very good about enforcing license.

Edit just checked. They do not have the license warning anymore ( am going to see if they offer a model registry of some sort or some other way) but you still can not specify walls or infill. I checked the XY Main for the LowRider and it was $18, that is one part there are 40 or so parts. That could not have been cheap. My kit is $65. Kind of a bummer anyone that pays all that money and gets MPCNC parts is going to have a very poor experience.

Man, I’m really sorry then. I had sent him each model and told him settings to print. Looking back at my receipt I seem to have paid a little over that, though it seems to be shipping cost. I swear in my original price spreadsheets it turned out much cheaper.


EDIT: I have your printed parts bundle listed as $165 at the time. I think they may have also been out of stock.


Sorry, I’ve been at a hot springs with no internet.

Yes, I get it, and yes, I want you to have all the money and fulfilling work in the world. You deserve it, this is a cool machine.

I have been using linux and other open source software for a LONG time… I believe in open source.

If I want to make improvements or changes… You can say no? That’s kind of a bummer to me.

I suppose I could be an ass and just redesign the parts MY way, making essentially the same machine, but with different parts. The idea is sound, the specific parts are not important. I could do that. I don’t WANT to do that. It’s a dick move, and I don’t want to do dick moves.

You’re limiting the machine to you. If you have a heart attack? If you decide not to allow NEMA23 motor mounts?

Further, why should I make improvements, suggestions, or anything if it’s all YOURS?

This is the strength of truly open source… a project that depends on ONE person is weaker than a project that doesn’t.

hmm… and I’m not sure if you’re correct about people’s ability to sell the parts once printed with your CAD files? I’ll read up on that. Copyright is not Patent, and they protect different things.

Someone else said it wouldn’t be noticed if I cranked out a few parts for friends… I’D notice. That sort of thing matters me, and I want to support projects that allow me to spread the good word to friends without restrictions.

Me asking about intent was just… wanting to know your intent with this machine.

If this is just about money, and you’re going to tightly control what can and can’t be done… improvements have to go through you… Well… It’s not going to get the robust improvements it might otherwise get… And I do want to put my time and energy into things that make the world better for everyone.

I teach a class on CNC basics at a local non profit. Do I tell people about this? It’s a neat machine. Frankly, it’s more interesting than say… openbuilds… but they ARE fully open sourced.


Hmm… Why is this a bee in my bonnet?

I think this is neat and I want to contribute. I’m more interested in contributing if it’s open to everyone. I believe in the power of open source to find bugs and create quality products using lots of eyeballs. And I believe that depending on one person makes a project weaker.

Sorry if I’m being a PITA. I just want to… I have principles, and they matter to me, ya know? I assure you, it’s a complete PITA shopping for shoes as me. :smiley:



Nope, you can do all the improvements you want, and use them as your own. Just you can’t forward them without explicit permission from Ryan.

See the many threads about such improvements (for example the Double beld setup) which Ryan publicly approves of .

Yet, as far as I understand, Ryan has been bitten before with people providing alternate files that didn’t improve much, if at all, and since his support effort is already quite intensive, he doesn’t want to have to additionally support “alternate” builds.

He’s had also people selling badly printed parts, which also isn’t good for MPCNC.

To be able to integrate other contributions, he would need to test them himself, and that’s another whole can of worms.


Still, I’m absolutely certrain that if he sees other people showing good improvements to his machines, that can be integrated in his builds, he’ll probably use them as an inspiration at next iteration, by implementing them his own way, with his knowledge of how to make easy to print, without support parts.

(Sorry Ryan, I hope I haven’t gone too far off what I understood from your different posts on the subject…)


There’s pages of modifications available for the mpcnc. Piper 1 is a 3d printer using the linear motion of the mpcnc. The artisan 3 and Plastic Monstrosity use similar linear motion components as the mpcnc and lowrider.


There is a difference between allowing people to modify the machine and being closed source. Many cars and motorcycles are closed source in a sense, but that doesn’t stop the industry from making carburetors, wheels, body kits, turbo kits, engine management, etc.


It’s not black and white. The term open source has a range of things it applies to. Original Prusa printers are open source. But their parts are hard to manufacture, and there just aren’t places to buy the MK52 heat bed, for example. Even though it is open source. Ubuntu is installed on windows. Red Hat charges for support, but that includes their software repositories. GPLv3 can’t be used hardly anywhere because it forces other software to be open. It’s just not possible to draw a line in the sand with the term open source. The qualities you want aren’t drawn on that line.

You want to edit the parts. You just don’t get the STEP files. You want to build the machine yourself, or have your class build them? You want to use open source tools like Linux, Machine Kit, octoprint, Marlin, grbl? You want to fix it yourself when it breaks instead of ordering from the one place that sells replacements? You don’t want advertisements or proprietary parts or data mining?

I’m also a huge proponent of open source. I have been using Linux as my desktop environement for over a decade. I use open source tools for work and I contribute to FOSS projects all the time. I think this project has just as much merit as any open spurce hardware build. I can’t make my own Prusa MK3. I can’t make my own E3D hot end. But I can make my own MPCNC.


\o/ Yes That !


And since the STL files are available, we can also import them, “duplicate” them in your CAD software, and adapt the parts for our needs with no problem. Just we’re not allowed to make money on them, and may not muddle MPCNC’s pool with copycats of uncertain quality. (uncertain in both directions)

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I’m curious as to what your end game is here? Why specifically do you want it open source? What improvements do you want to add? What would your contribution be?

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No I can’t tell you no, that is not true. Do you know of a time I have told anyone no? I had said it publicly many times. I offer dimension to those that need it, and I offer my advice in private. Many people do not realize why the part they made is not “better” I offer some changes and usually they make them. So SHHHHHHH I help other people too.

No that is, not true at all.

The machine is out there in the world for free…still. Why do you care if some other company can sell it? Plenty of work happens outside my bubble. Did you know there is a Washington state engineering course based on my machine but one of there own modifications? There is absolutely nothing complicated or proprietary about this. If I die nothing is lost…I do eat like a 15 year old so heart attack is bound to happen, love me some nuggets and fries with a Dr. Pepper.

There are 23 mounts on thingiverse…I used to have some of my own design. Have a look at the FAQ’s. Maybe just a bad example choice. I tell people not to do things all the time, I am wrong a lot of teh time as well…5’x5’ build, milling steel come to mind.

Please do, the license is valid in most countries. We had had many international issues that were quickly resolved without many hurt feelings once people were educated on the license structure.

??? Where is this money thing coming from, tight control (since when, proof?), improvements do not need to come anywhere near me. Have you looked at the thousands of thingiverse parts? As for money…I work out of a bed room and tiny garage. I have help about 3 hours a week, When I start hording money feel free to bring that back up. Hence the protections, If I lose much business to some other company I will have to get a job and then you will have even less than if I had a heart attack.

You missed the point of that statement, he is on your side. P.S. you should see the things he makes, he never listens to me when I say it shouldn’t be done (thankfully)!

Slippery slope, different parts does not necessarily make it your design.

At this point we are not talking about the same thing. You are saying some very incorrect things. I think you need to carefully read the license. A very human readable version is located in the Thingiverse link of my parts. From there you can find the full lawyer version if you need more detail. I really don’t want to say much more until you understand this better. You can not fight for a cause you do not understand at least a little better.We are very much on the same page I just don’t think you realize it.

At this point I have not released my CAD part files for most parts (see FAQ’s), and it is non-commercial.

I have been pressured to go full open by a company. Their line was “are you scared, we are fully open why not you?”. 80% of the machine could not easily be made at home…or even in a maker space, just words to some, Marketing words…I feel I am more open source than they could ever be from day one.

Naomi Wu, is working with a manufacturer now (creality?) tweeted about people voting on what open source printers she should have made in China, Prusa and all the others were on the list. Prusa was not happy. In my opinion he should be non-commercial or fine with it, but that is not my company. He can do his thing how ever he wants.

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