Building the MPCNC (1): Parts and component choices!

Building the MPCNC (1): Parts and component choices!


It is time. We’re building the MPCNC!
I actually had one more video planned to go up before I started on this build, but Adobe
just didn’t want that to happen. So… we’re going to live-build the MPCNC
together, like with Dolly, the Prusa MK2, uh, clone, but unlike that, this one is going
to be the real deal. A full MPCNC in the burly version, which is the current, sturdier design
variant. In this video I just want to go over the parts I’m using, why I’m using them
and what alternatives there are. But first, what even is the MPCNC?
As a full explainer, check out my interview with the MPCNC’s designer from MRRF 2018
up here, but basically, this is a closed-source, 3D-printable, where it makes sense, CNC router,
engraver, let’s just call it a light-duty CNC. The base is any sheet of flat material
you want to use, the frame and linear rails is steel tubing, if you have it available,
you can use electrical conduit, the motion is done with just 6mm GT2 belts and NEMA17
motors and a 3D printer control board, any board you have will basically work. And of
course, there’s a toolhead, I’m using a spindle, but you can of course also use
a 3D printing head with an extruder and hotend or a pen plotter, drag knife, paste extruder,
whatever you want. The nice thing is that you can easily scale the machine by using
a larger base and longer tubing and belts. I’m building mine with roughly a 50x50cm
build area and 15 or 20 centimeters of vertical travel. I’m not exactly sure how large the
actual usable build area is going to be once you add fixtures, the tool and so on, but
it should be comfortably large in either case. So looking at these parts, it should be obvious
that this is not a machine that will be massively rigid and end up cutting stainless steel or
titanium, at best, I’m hoping for some drilling and light cutting in aluminum, but I think
this machine is much more comfortable cutting or engraving wood, plastic, foams, those sort
of softer materials. So, parts, let’s start with the printed
parts. These were printed from simple PLA, which is rigid and strong, exactly what you
want out of a CNC frame. Unlike the topology optimized shelves, there are screw heads pressing
against the parts and potentially hot components touching the prints, so I’ll have to see
how well it holds up. These parts were printed on a bunch of different printers with a bunch
of different PLAs and, I don’t know, the color scheme is definitely… disagreeable.
Overall, this is one and a half kg of filament, two small spools, so it’s quite a bit of
material, but these parts are designed quite chunky, so you don’t need to use your fanciest
filament for this. In fact, I used up random bits of old PLA that I had hanging around,
so excuse the color scheme. The set of parts is the Burly set from V1
engineering, and I’ve also printed a mount for my spindle, I believe off thingiverse.
There’s a healthy ecosystem of modified parts available already.
And speaking of the spindle, calling this thing a spindle maybe is a bit much, but that’s
what the seller is calling it. I’ve used a similar one in the Mendel Max CNC conversion,
but this is a brushless version of that “motor with a chuck” assembly. I’m hoping that
the controller might be a bit smarter and give consistent torque over the RPM range.
For the brushed version, the only sort of RPM control is by adjusting the power supply
voltage, but this one has a special power supply included in the kit that not only lets
you adjust RPM, but also has a digital readout that displays RPM in real-time, and I think
that’s a huge deal when it comes to tuning in cutting parameters, it just takes the guesswork
out. The alternative is using a trim router as I’ve got in Bob, the Sienci CNC, but
I find that to be one of the worst options, as they tend to be super noisy and in my case,
getting collets for the thing turned out to be an absolute nightmare, so I could only
really use 6mm shaft endmills, which is actually really large for how rigid these small machines
are. These smaller motors just have an ER11 collet chuck, and the collets for those are
incredibly cheap and available everywhere. It’s just a standard size.
Next up, the frame. For the base, I used this piece of particle board that I glues some
MDF to, I like the smooth and flat surface of MDF, you could probably use just a thicker
piece of MDF, or plywood, really, as long as it’s flat and you can screw things to
it, you should be fine. You could probably even use a T-slot table, that way you’d
directly have a way of clamping down parts. These tubes doubles up as both the frame and
the linear rails, so it’s a really good idea to use something that’s fairly rigid.
The MPCNC files are available for 23.5, 25 and 25.4mm aka 1” tubing, which I believe
may be fairly common in the greatest country of the world, but for me, I could really only
get hold of 25mm tubing, this really is just standard tubing stock, I ended up using this
ground stainless version, which is more expensive than conduit would be, but not unreasonably
pricey by any means. The sizes that would be really easily available here would be for
things like galvanized water pipe, which comes in nominal ½” and ¾”, which actually
is 21.3 and 26.9mm on the outside. Don’t ask me how those sizes make sense, but maybe
we’ll see an MPCNC version that supports one of those sizes at some point.
Now, for the motion system, I grabbed some random NEMA17s, as well as a fresh roll of
GT2-2M 6mm glass fiber belt, the same stuff that’s being used on 3D printers; interestingly,
V1 say that you should not use this steel-reinforced belt, so I’m not doing that.
For electronics, I’m using the Duet Wifi – for now. It has strong drivers and great
software, but I may swap it out for something simpler at some point as I might need the
Duet back in my Mendel9000 test platform which, yes, is finally printing. It should be an
easy configuration swap moving the board between machines.
So one last thing you need is a bunch of fasteners. You can use both metric or imperial sized
hardware, but the parts are designed with imperial parts in mind as far as I’m aware.
Oh, and you do need a leadscrew and a coupler and pulleys and cables, but that’s really
unexciting stuff that you kinda need for every build. The same goes for tools, you need a
few basic things like hex keys and maybe a few spanner for some nuts, and I believe you
also need a way to drill a few holes into these tubes for the Z-axis. But, for example,
the base, you can get cut at pretty much any home center in any size.
Now, you can buy all these parts, minus the tubing, and I think the base, directly from
V1 engineering, but of course, there’s also the option to self-source, which I tried,
and I ended up a bit cheaper than what the kit would have cost. Of course, which option
is better for you depends on where you live and what your preferences are in self-sourcing
vs. buying a kit, but just like with Dolly, I’ve created a full list of parts over on
toms3d.org with options of where to get each part.
So over the next days, I’ll be building this MPCNC together with all of you in a series
of livestreams, the first one will start tomorrow on Sunday, August 25th 2019, so if you’re
free, come join in and maybe even build along, the link is in the description so that you
can enable that notification,but these streams will also be available as recordings for your
enjoyment. The great thing is, you can skip forward in recordings!
So I hope to see you there! As always, thank you for watching, leave the video a like,
get subscribed or even support the channel through YouTube memberships or Patreon, and
I’ll see you then! Bye!

100 thoughts to “Building the MPCNC (1): Parts and component choices!”

  1. I tried to build one of these a couple years ago and ran into issues with delaminating and brittle parts. These were also older generation STL. I look forward to seeing how the 'burly' parts work out.

  2. I'm greatly looking forward to seeing the build! If I had the space, I'd love to mount the system to a marble slab and bolt everything to that. Do you expect much deviation in the linearity of your pipes?

  3. Although spiny lobsters superficially resemble true lobsters in terms of overall shape and having a hard carapace and exoskeleton, the two groups are not closely related.

  4. Well I dared you to build it, glad we didn't bet on it, but I was pretty sure you were not going to build it. I am really not sure how to feel about this….excited…worried. Either way I love seeing everyone's take on this design. I am sure you will have some fun along the way. Can't wait to see that crown!

  5. Can anyone help me resolve a problem with m printer? After like 20 layers every layer change results in underextrusion followed by overextrusion. I am trying to print single wall for calibration (I did the 100 mm filament calibration). The problem occures no matter of retractions settings.

  6. The steel reinforced belts work harden going around the bearings on this machine and break. That's why we don't use them.

  7. How feasible would it be to make a series of every DIY printer available? HyperCube (EVO), Voron2, etc? And then rate it based on build complexity, cost, quality etc?

  8. I'm planning also to make MPCNC and I just finished printing the parts with my 3D Printer!
    Nice video as always! Keep making!!!

  9. This seems great but I dont like the belt design. If it had lead screws I would have already made it. I am still waiting for the Dremel CNC version with a 1.5kW spindle mount.

  10. When you are ready to throw that spindle in the trash – I recommend a Makita clone (Katsu, etc.) They're very cheap, and you can even get replacement parts. The added bonus being that you also get a free trimmer router. 😉

  11. Just this week I started printing my mpcnc, the steel tubing is also cut already:D Let's see who cuts aluminium first 😀

  12. Never ever print any construction parts for moving machine from basic PLA. 😉 (Parts will degrade over the time even under very small stress. The rigidity will be worst and worst, vibrations stronger.) CPE or even PETG are not so expensive and better here.

  13. Why not go for a SKR V1.3 instead of the duet? It is also 32bit and you can choose your own stepper drivers like for example the tmc5160.

  14. That work bench with shelving you have in the back right: did you make that out of other parts or did it come like that? Looks like something I could use 😄

  15. I have a partially finished one in my basement currently. You'll want to do something for cable routing, that's what I'm currently stuck on. X and Y are ready to be installed, but I need to come up with a good way to send it to the center assembly.

  16. Hi Thomas The table you have aside with the shelves where you bought it from If you can post a link I would love to know thanks

  17. Don't you need 5 stepper motors to build the MPCNC? 2 for the X-axis, 2 for Y and one for the Z-axis? In the video and on your parts list you only list 3 stepper motors.

  18. Good luck, should be a fun build! I built mine about 5months ago and it works great for me. I opted for the full size Rambo board so I could easily do auto squaring.

  19. Tom, I'd love to see a hybrid approach including both additive and subtractive manufacturing utilizing a 3D printer for the rough workpiece followed by MPCNC milling to finish the piece!

  20. Oh you too are building one? Nice, im currently setting up the electrics for mine. 😀
    On the Makita router, ive bought a 6mm to 3,175mm adapter from a german manufacturer, wasnt as cheap as the chinese ones but this one actually had good tolerances. Runout below 0.03mm, which is decent enough for a router being used in a half plastic cnc imho.

  21. Just in time! I just finished the Dolly/Prusa clone project today. Looking to follow this new project. Thanks again for putting this together.

  22. I just got through upgrading my mpcnc to the burly version. This machine is insanely capable considering its some plastic and conduit. I look forward to the live stream

  23. I did my mpcnc a year ago. But one of the best things I found was don’t think of conduit. I found that towel rack tube was perfect instead (25mm chrome stainless steel tube) and was way cheaper and came pre cut in standard length.

  24. Tom, please beware that chinese spindle gets pretty hot in use. Eventually the PLA spindle clamp can release the working spindle as the PLA gets soft. That was so close here as I saw the cut quality decrease, I emergency stoped the machine just before seeing the spindle falling. A real piece of chance! You will probably need to upgrade your splindle mountings to ASA parts or OEM aluminium mount as I did. What about a modern board alternative to the old timer MKS Gen ? I mean a Fysetc Cheetah or, if you like changeable drivers a Bigtreetech SKR ? I also strongly recommend ABEC 7 class bearings. Good luck with the build. And oh, the colours reminds me the joyfull kindergarden, kinda FisherPrice MPcnc ;D

  25. Hello, I would recommend rigid couplers to replace the flexible, because with the movements, they will relax and distort the steps.

  26. I printed it originally in PLA, but after building it and not getting around to wiring it for a few months, the PLA cracked all over the place. This was not under any kind of a load, just the pressure needed to hold the plastic to the metal conduit. I reprinted everything in PETG and it has held up considerably better.

  27. I'm interested in making a CNC hotwire foam cutter. Is it possible to adapt this for my use?
    What about the software part? Thanks.

  28. You could build this out of pipe and angular components they use to make bus hand holds/railings out of. It would result in a very rigid structure. Push the envelope even further and you could use drawn (not seam welded) pipe (quite straight) and get even further bonuses.

  29. The affiliate links don't seem to work properly ( might be me or my browser) Example the amazon link takes me to Amazon japan ?????

  30. Oh, I so wish you would have done this earlier. I just finished mine and I know your build video would have helped me tremendously. Wonderful! Always great videos.

  31. I’m really looking forward to watching this build series. I’d really love to build an MPCNC, and I still might, but I have no idea where I could run a loud machine that creates sawdust or shavings.

  32. Great project, I already thought about building this for months now.
    Where you got the digital readout from? None of the kits on AliExpress (I guess you bought the Daedelus 400W?) have it included.

  33. Really looking forward to this build, Thomas.

    Ryan at V1 Engineering is super talented and very attentive to his customers, so, hopefully your build will go smoothly.

    As I suspect many who follow your channel are, I'm a "digital fabricator", with feet in both the additive (3D printing) and subtractive (CNC) spaces. While I have experience on many smaller form factor CNC's, my current machine is a Viper XP from CNC Factory (5'x10', 10HP spindle, automated 10-tool changer and vacuum hold down). It's my first experience with a machine this large and powerful, and it's been a game changer.

  34. Look'n forward to this, it's been on my to do list for quite some time, just waiting for the physical space to free up.

  35. I've always thought you needed to branch out into different projects like this. I've got lots of the parts for this too, maybe this'll get me started on it again! Thanks Tom!

  36. I am printing for 2 weeks now. 🙂
    I use petg.
    In old pla prints i see allot of splitting over time.
    37 print hours to go. 5 big parts.
    I don't like to leave my printers unattended.
    My board is a SKR 1.3 with TMC 2130.
    Hope te get sensorless homing working.
    If the 2130 is not strong enough i upgrade later to the TMC2209.
    I use the SKR1.3 with tmc2130 on my ender 3 and prusa i3 clone 2014.

  37. Another great build to follow.
    Have you thought about doing the FDM SLA printer on thingiverse?
    Starting that as soon as my screen arrives

  38. Heard abt the makita collet problem.. I faced the same and then solved it by buying end mill with different shank size and flute size.. just buy the one with 6mm shank and the desired flute dia.. u can find lot of them in AliExpress..

  39. You might want to look at the double belt modification done by Brauns CNC on YouTube in his video Building a (modified) mostly printed CNC

    Directly underneath the belts he places a wooden board standing upright with second belt glued to it, resulting in a sort of toothed rack. This completely removes the tension on the drive belt outside the idler rollers and instead transfers it to the bottom belt, which can't stretch because it's glued down on it's entire length

  40. I built one of these, the only problems I had were that I cheaped out and tried to use a raspberry pi with an arduino based controller and open source software. It worked well with simple parts (2.5D cuts) but when I tried to do full 3D surfaces, it always quit or went crazy. I ended up buying a USB controller from amazon that is compatible with Mach3 (Mach3 loaded up on a new laptop) and have yet to have a single problem. Also don't cheap out on the stepper drives, had lots of problems with a cheap drive just quitting in the middle of a cut.

  41. DO NOT use galvanized water pipe or any galvanized material. Galvanized pipe is VERY ruff & will destroy your bearings & any other movable parts. You will have to remove the galvanized material from the pipe by heating it & galvanize is toxic & you risk warping the pipe.

  42. The filming setup truly looks incredible. I just got a 4K monitor and this is a treat to watch. Same for the B-roll with the gliding shots…. super nice! Keep it up, Tom.

  43. Hey Tom, maybe you can look up the ‘RS CNC’ i think its a stronger machine I’m building one myself right now

    Keep up the good work! Looking forward to this build

  44. I see the mpcnc is making rounds in the 3d printing YouTuber circles .. like everything else. Is it just me or is this a deja Vu?

  45. Hi Thomas, really looking forward to the rest of the video's. Question, I take it you used PLA because you had it lying around and it was easiest and cheapest. What do you thing is the best material to print these parts in? I was thinking PETG?

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