13 ms·

Show HN: I built a CNC-machine from scratch, using 40x 3D-printed parts

462 points by mfi 5y ago

mfi 5y ago
I just finished my latest project, building a CNC-machine from scratch using an Arduino Uno, GRBL and 40x 3d-printed parts. It’s able to mill wood and aluminium, up to ~20mm thick. As with all my other projects, I think they should be executed in the open where other people can learn from my mistakes and get inspired to build their own things! Therefore I’ve spend a lot of time writing a free complete tutorial of the build, documenting every step with text and detailed images, creating a complete bill of materials (including STL-files for the 3d-printed parts) etc. I don’t want any dependencies on DIY-websites, so I’ve hosted it on GitHub, where anyone can clone it locally. I built this machine to gain more knowledge about mechanical engineering, electrical wiring, stepper motors, GRBL, CAD, CAM etc. Also, I guess I can build new fun things with the machine? Overly-engineered birdhouses maybe? Setup: * It’s running on an Arduino Uno, CNC-shield and GRBL. * 40 parts are 3d-printed (all the red parts in the video) * It’s based on Ivan Miranda’s blueprints, but I’ve adjusted some parts and structured the bill of materials. * It uses 2x 19:1 geared NEMA17 stepper motors for the Y-axis and 1x for the X-axis. The Z-axis is using a standard NEMA17 motor. * HTD5M belts and pulleys are used for X-axis and Y-axis. GT2 belt and pulleys are used for the Z-axis. If you have any questions, feel free to contact me. You’ll find my email in the top of the guide :)
- billconan 5y ago
  very cool! thanks for sharing. I don't have the equipments to drill holes on aluminum parts, I will probably need to use https://8020.net/ https://8020.net/ to build one.
  - mfi 5y ago
    Aluminium is quite soft, so it might work if you have access to a screwdriver and a step drill
    - haliskerbas 5y ago
      I’m not an expert here but I’ve heard 8020 is expensive enough such that purchasing a drill press would probably be cheaper, if feasible, correct?
      - genewitch 5y ago
        There is also handheld drill press rigs that may be useful.
  - arnado 5y ago
    You might also want to look at the mostly printed CNC, which uses standard conduit/pipe for the frame. https://docs.v1engineering.com/mpcnc/intro/ https://docs.v1engineering.com/mpcnc/intro/
    - AdamTReineke 5y ago
      Be warned these plans require you to drill a couple holes in the conduit. I managed with just a handheld drill though the holes weren't quite aligned. Definitely use a file or hacksaw to create a flat spot on the conduit where you want the hole so the drill bit doesn't wander as easily.
      - Nick87633 5y ago
        Or a center punch (helps on flat metal too). One favorite trick of mine is to print out 1:1 drill pattern drawings and center-punch through the paper onto my metal workpiece for all the drill locations. Fast and accurate.
        dekhn 5y ago
        Basically, 2D printers (you know, those $150 things) are exceptionally high precision and accuracy tools for making 2D drawings. I've been using printers for years and it never occurred to me you could use it to print a (for example) 10cm square.
        jacquesm 5y ago
        You can if you are really nifty do limited scale PCB manufacturing this way. https://www.instructables.com/Creating-Printed-Circuit-Boards-with-a-INKJET-Prin/ https://www.instructables.com/Creating-Printed-Circuit-Board...
        sokoloff 5y ago
        Fusion360 seems to try to prevent you from exporting PDFs with the free hobbyist version. One tip that I discovered was to create a CUPS printer on a Linux VM that saves PDF files. (I found it printed slightly off sized if I sent a 2D drawing straight to the printer.)
  - convolvatron 5y ago
    I use a cordless hand drill to drill and tap aluminum all the time (as does this project). adjust the speed until you are pulling out long ribbons instead of dust. you can use a little oil, but its not necessary. the only issue is trying to stay perpendicular to the work, but usually a little deflection doesn't matter. also pay attention to 'wowing', where instead of drilling your perfect round hole the drill bit starts to bounce around a triangle or pentagon and you end up making too big a hole. its often best to start with a pilot drill and then a final pass to clean it up. also its often easier to use a centering drill to setup the holes. it provides a pocket for the drill to rest in so that it doesn't wander, and you can use the centering drill to fine-tune the hole pattern before you make it permanent.
    - sokoloff 5y ago
      To easily stay perpendicular to the work, use a tap guide block. You can 3D print one or drill one out of stock on a reasonably square drill press.
  - IgorPartola 5y ago
    I picked up a used drill press for $45 or $50 (I don’t remember now), and a tap and die set from Amazon for about $20. 10/10 would recommend if you have the space.
  - 0des 5y ago
    Believe it or not, aluminum can be treated the same as wood when it comes to tools. Any drill that can drill wood can drill aluminum.
- zwieback 5y ago
  Awesome. Can it mill aluminum? If so, would you consider replacing some of the 3D printed parts with machined parts?
  - mfi 5y ago
    Yeah it can! Ivan Miranda, the guy who has created the blueprints actually updated his machine with aluminium parts, milled on the CNC-machine. That might be something I'll do in the future!
    - jhgb 5y ago
      Von Neumann probe when?
      - jacquesm 5y ago
        Right after you figure out how to 3D print solid rocket fuel without things going 'bang' prematurely.
        yetihehe 5y ago
        If you print Potassium Nitrate/Sorbitol[0] with direct granule extruder[1] you could do it. But this will probably need additional toolhead for engine body[2] (plastic-fiber composites DO have enough strength to survive using KNSB in engine, I've seen tests, but those are not publicly available) and for ceramic nozzle[3]. With some experimenting, probably doable. [0] http://www.nakka-rocketry.net/sorb.html http://www.nakka-rocketry.net/sorb.html [1] https://hackaday.io/project/181165-my-machinery-2021-direct-granules-extruder https://hackaday.io/project/181165-my-machinery-2021-direct-... [2] https://www.sciencedirect.com/science/article/pii/S2212827117307059 https://www.sciencedirect.com/science/article/pii/S221282711... [3] https://reprap.org/wiki/Ceramic_Extrusion https://reprap.org/wiki/Ceramic_Extrusion
- eduardosalaz 5y ago
  The CNC Shield is a blessing, shame the Gerber files aren't being published for newer versions.
  - mfi 5y ago
    100%, it helps so much with the wiring.
  - thawkins 5y ago
    https://www.pcbway.com/project/shareproject/CNC_Pro_Shield_V3_00.html https://www.pcbway.com/project/shareproject/CNC_Pro_Shield_V...
- dekhn 5y ago
  I understand you put thought and time into your approach and it was a hobby to learn more abotu the process (and thus you know about MPCNC but decided to make your own). I've also build similar systems and I've learned some timesaving tricks that have paid off in terms of hobbyist enjoyment. I really like buying the majority of the parts from a place like OPenBuildsPartStore, rahter than assembling frames from channel manually. Time/cost/quality tradeoff is hard to beat here. I strongly recommend switching to Grbl_Esp32 https://github.com/bdring/Grbl_Esp32 https://github.com/bdring/Grbl_Esp32 with external controllers (this board https://www.tindie.com/products/33366583/6-pack-universal-cnc-controller/ https://www.tindie.com/products/33366583/6-pack-universal-cn... with these plugins https://www.tindie.com/products/33366583/external-stepper-motor-driver-ver-11/ https://www.tindie.com/products/33366583/external-stepper-mo... and these controllers https://www.amazon.com/STEPPERONLINE-1-0-4-2A-20-50VDC-Micro-step-Resolutions/dp/B06Y5VPSFN https://www.amazon.com/STEPPERONLINE-1-0-4-2A-20-50VDC-Micro...). That's what I ended up with because tuning current using the little pots is dumb, and you want a TON of current going to those huge motors. ESP32 + Grbl has a bunch of nice features that aren't in plain old Uno GRBL. My system has high torque NEMA23 with no gears (same motor for all 3 axes), I can't see any situations where adding more torque to the X or Y axes using a smaller gearer stepper makes sense.
  - giantg2 5y ago
    "I can't see any situations where adding more torque to the X or Y axes using a smaller gearer stepper makes sense." Generally agree. Torque is only needed to a specific threshold. If it requires a lot of torque, then that's probably a good sign to slow the movement down (for the sake of the machine's longevity).
    - jacquesm 5y ago
      On the contrary, plenty of tools need to move and chip otherwise they'll get dull, cutting speed is a function that increases a machines' longevity. But cutting speed does require a solid mechanical setup, drivers that can source some current and a drive train that does not suffer from over or undershoot ('slop').
- roland35 5y ago
  what material did you use for 3d printing? I would think PETG or ABS is probably best?
  - mfi 5y ago
    I actually used normal PLA
    - naasking 5y ago
      PLA is actually the stiffest of those materials, just keep it cool enough that it doesn't warp! I expect that would only be a problem around the spindle which can get quite hot, and maybe stepper motor mounts.
  - moepstar 5y ago
    You most definitely want to avoid PETG as it is pretty... flexible... PLA is the way (the MPCNC, for example, is designed with PLA in mind) in this case, as with ABS you most likely need higher printing temps, bed temps, an enclosure to keep even the slightest drafts out...
- giantg2 5y ago
  You mention aluminium. Any plans to add a lubricant sprayer?
- 2muchcoffeeman 5y ago
  >I can build new fun things with the machine? Overly-engineered birdhouses maybe? I don’t have space for a workshop. I live in an apartment. So I’m pretty limited in the sorts of materials and tools I can use. 20mm of wood is probably quite useful. My table top and shelves aren’t 20mm thick. If this can go through MDF I’d say it’s really useful.
  - dekhn 5y ago
    this sort of machine could easily carve 5-10mm of MDF in a single pass. It's awful loud though, even when enclosed. What I recently made: a terrain map of california cut into plywood. It's several feet by several feet (~600mmx600m), 0.75" (almost 19mm deep at the lowest points in california) and wall-mount-worthy.
    - te 5y ago
      Sounds really cool! Got pics?
  - fuzzylightbulb 5y ago
    Unless you have an incredible dust collection system in place, I would seriously reconsider any potential plans to cut MDF in your apartment. The particles are very fine and you will find it everywhere. And that is to say nothing of the particles that you'd be inhaling.
- jacquesm 5y ago
  What a fantastic project. Is the design parametric, in other words, are there parts that would need to be scaled up to have larger x, y or z axis or are those all off the shelf and are the various STL files for the components the same if the design is scaled up?
  - mfi 5y ago
    Glad you like it, most cred should go to Ivan Miranda for the core design, I just executed, updated some parts and wrote a guide around it :) No, it's not parametric in that way. But it is possible to extend the "mill-bed" by: * X-axis: Increase length of frame and bridge profiles. Buy longer MGN12H rails used for the X-axis. * Y-axis: Increase length of frame profiles. Buy longer MGN12H rails used for the X-axis. * Z-axis: Increase the vertical beams between lower and upper frame. Buying longer MGN12H rails used for the Z-axis and a longer acme rod.
- aquaphile 5y ago
  Nice work! You made a lot of great design choices. +1 to those that recommend upgrading your extrusions and motor mount on future iterations. The rigidity is well worth it. If you are ever deciding between belts and ballscrews, I recommend ballscrews. It is worth the extra $$. For the milling of aluminum, I suggest adding a compressed air nozzle. It will make a huge difference in milling AL. Also, some of the new bits are fantastic at hogging out aluminum. For reference see pic at https://drive.google.com/file/d/1BWvOOwmaQljwhdBzYNvilYDKdsyCkXeR/view?usp=sharing https://drive.google.com/file/d/1BWvOOwmaQljwhdBzYNvilYDKdsy... We built our own 5-axis CNC too, to do large envelope parts trimming. It looks like Frankenstein, but works pretty well. See a pic at https://drive.google.com/file/d/0Bydp4fsq-EhtUndOTlZTcU1fTEU/view?usp=sharing&resourcekey=0-rlUPDkgckiSJ5pKbqfnhNA https://drive.google.com/file/d/0Bydp4fsq-EhtUndOTlZTcU1fTEU.... We use it to trim the chassis parts for our baby car seats at https://kioma.us https://kioma.us Keep on building!
jaxn 5y ago
Really neat project! Maybe I missed it, but is there a general cost estimate anywhere? I saw the BoM, and assume most the cost is in the router and stepper motors, but is this like ~$500?
- mfi 5y ago
  Thanks! I think it spent around $1100 in total, but then I paid for fast shipment and ordered quite a lot of parts that I ended up not using. You can probably build it for $600-$1500, depending on where you source the parts, what quality you buy, speed of delivery etc.
cinntaile 5y ago
Do you know how accurate it is?
- mfi 5y ago
  I milled a test block in wood to check the accuracy, and it was sub-millimeter accurate. I can't measure further than that as my tools doesn't allow it. But I doubt that it's super accurate due to the 3d-printed parts, aluminium instead of steel etc.
  - wolfram74 5y ago
    Being a spherical cow loving physicist, I still get caught off guard by what counts as "precise" in engineering contexts. Even when I'm making stuff in meat space I don't think I've ever bothered to intentionally get better than 1% relative precision.
    - sokoloff 5y ago
      For a framer, 1/8” is precise enough. For a finish carpenter, 1/32” is precise enough. For a 3D printer, 0.004” is precise enough. For a machinist, 0.0005” is precise enough.
      - curtain 5y ago
        0.004" is read as "four thou", and 0.0005" as "five tenths", as in five tenths of a thou, FWIW. I only picked up imperial thanks to binging This Old Tony videos.
        sokoloff 5y ago
        If you enjoy https://www.youtube.com/c/ThisOldTony https://www.youtube.com/c/ThisOldTony, you might also enjoy https://www.youtube.com/c/Clough42 https://www.youtube.com/c/Clough42 https://www.youtube.com/c/Blondihacks https://www.youtube.com/c/Blondihacks and https://www.youtube.com/user/JohnGrimsmo https://www.youtube.com/user/JohnGrimsmo
j_walter 5y ago
Reminds me of the Root CNC project. https://rootcnc.com/ https://rootcnc.com/ Great work!
- mfi 5y ago
  Haven't seen this one before, thanks for sharing!
- IgorPartola 5y ago
  This looks great. I do love that MP-CNC tells me immediately the approximate cost. Wish more projects did that. I can’t tell if a Root 4 would cost me $200 or $2,000 without looking for all the parts individually.
  - j_walter 5y ago
    I did look for the parts because I was interested in getting one made...however many of the parts still aren't ready to go (control side), but the hardware cost other than that was fairly reasonable in the $500-800 range depending on how big you were going to go and which motors you chose to use.
542458 5y ago
Nice! I built an older model MPCNC years ago, and was able to get pretty great results with it relative to the tiny cost and huge flex in the frame. I managed to cut some brass Christmas ornaments that I’m pretty proud of. I like that you’re using racks here - the belts on the MPCNC were a major weak point in my experience. I wonder if you could get away with 3D printed racks and pinions. There’s a lot of structural plastic in there already, would the hit from accuracy from using lesser racks make a difference?
- bmsleight_ 5y ago
  Love to see the brass Christmas ornaments have you a photo ?
- metal_am 5y ago
  You can buy ball screws somewhat cheaply direct from China. That'd be the way to go.
amelius 5y ago
Most hobby CNC projects have only 3 degrees of freedom, whereas most high-end commercial projects have a few DOFs more.
- sokoloff 5y ago
  3-axis mills are the most common configuration for commercial mills (probably by a wide margin).
- thedingwing 5y ago
  This is not true. 5 axis mills and 9+ DOF CNC mill/turn centers exist, and they are becoming more common, however 3 axis vertical mills are still the backbone of most machine shops.
rytis 5y ago
Great work!! What router bits are you using for milling wood and aluminium?
- mfi 5y ago
  Thanks! I'm still very new to the CNC-space, so I'm currently exploring different bits. So far I've only bought some low-cost flat end mills from Amazon, but I'll probably work my way up to higher quality when I've used it more.
- dekhn 5y ago
  carbide: https://www.amazon.com/gp/product/B0080CVUVS https://www.amazon.com/gp/product/B0080CVUVS as an example. it never dulls.
roland35 5y ago
Very cool! I am actually also making a 3d printed pen plotter! I love how easy it is to get common hardware like bearings, plus how nice it is to print parts on demand. Edit to add the link to the plotter: https://www.thingiverse.com/thing:2349232 https://www.thingiverse.com/thing:2349232
- mfi 5y ago
  Yeah, the 3d-printer is a game-changer in these type of DIY projects!
ElijahLynn 5y ago
The pictures on that README are insane! So HELPFUL! And, I already have that same Makita router so I am more tempted to try this... because of the pictures!
- mfi 5y ago
  Haha yeah, I spent quite a lot of time to document everything. I sometime have trouble following tutorials because they leave out things that are obvious to them, but not to the reader. So I've really tried to include every step in detail, even though they might be "simple" and obvious. What's stopping you? Go for it! :D
bartwe 5y ago
I recommend building a cnc, had a lot of fun building a mpcnc
phkahler 5y ago
Do any of these small CNCs support G02 and G03 for circular arcs? I was recently looking at G-code output from Solvespace and figure we need to update it to produce those codes rather than tiny linear segments. But will the home-built CNCs even support that?
- Robotbeat 5y ago
  I think Marlin supports it.
- vvoid 5y ago
  LinuxCNC will (http://linuxcnc.org/docs/2.8/html/gcode/g-code.html#gcode:g2-g3 http://linuxcnc.org/docs/2.8/html/gcode/g-code.html#gcode:g2...) - but your CAM may not. Edit: did not realize I was replying to solvespace, bring on the arcs!
  - phkahler 5y ago
    >> Edit: did not realize I was replying to solvespace, bring on the arcs! There's a guy working on a g-code template right now. It should substitute the g-code into the template on export so it's machine ready. I'd like to get into all that, but I'm still working on construction tools and stuff.
- opencl 5y ago
  Most of the small hobbyist machines I've seen (including this one) use Grbl, and Grbl does support G02/G03.
- dekhn 5y ago
  grbl supports arcs and it represents the most common Gcode firmware on these "home-builts"
MayeulC 5y ago
This got me wondering: most CNCs and 3D printers use switches for calibration, plus stepper motors for positioning. Has anyone tried to use cameras or a Valve Lighthouse (0.3mm precision), maybe with accelerometers and encoders, for tracking? That would allow the use of cheaper, faster, torquier, more efficient DC motors, as well as release the accuracy constraints for a lot of parts (depending on which part is being tracked). The goal would be to trade hardware complexity and price for software complexity, since it's easier to re-purpose software (and something like lighthouse base stations has multiple uses, so the price could be shared between projects).
- LeifCarrotson 5y ago
  Yes and no: No, no one I'm aware of has tried using DC motors and cameras instead of steppers to control a printer. But yes, industry uses optical technology in large CNCs all the time. Some homing switches are physical clicky switches, some are inductive proximity sensors, but an optical 'horseshoe' througbeam/fiberoptic sensor is the standard for highly repeatable sensor-based homing. Depending on your control system, homing to a hard stop by measuring motor torque can also be highly effective, then you don't even need switches. I've personally worked on a number of CMMs (coordinate measuring machines, basically a CNC with a probe tip for checking that something was machined within tolerances instead of a spindle for actually cutting it) that use 90V DC motors and Heidehein glass scales for positioning. We calibrate them using laser interferometers; another optical technique - just with a single beam. Those same CMMs are being phased out across the industry in favor of optical measurement systems, just because they're faster. Shane of the excellent "Stuff Made Here" Youtube channel recently made a big CNC painting robot that did optical tracking for a coarse positioning stage and used steppers for the local stage: https://youtu.be/osUTMnDFV30 https://youtu.be/osUTMnDFV30
- tupshin 5y ago
  I think there's a very big future in adding more (optical and other) feedback mechanisms to CNC machines, but 0.3mm resolution is really only good enough for the crudest of devices. For comparison, a typical ball screw, has positioning accuracy/resolution of around .02mm
gtirloni 5y ago
What's 40x? I feel brain challenged today as I can't understand what that means in this context.
- finder83 5y ago
  I read it as "40 individual 3D printed parts."
- wipash 5y ago
  They mean 40 separate 3D printed parts: https://github.com/maxvfischer/DIY-CNC-machine/blob/main/BILLOFMATERIAL.md#3d-printed-parts https://github.com/maxvfischer/DIY-CNC-machine/blob/main/BIL...
  - mfi 5y ago
    Exactly, I meant 40 unique 3d-printed parts
aidenn0 5y ago
Now we need someone to make a 3d-printer out of 40x CNC'd parts and we'll have a never-ending supply of both!
axegon_ 5y ago
Congratulations! I'm working on one in my spare time but I've decided to cram in as much features as possible(as far as not being able to cram all the features into an arduino or esp32 so ultimately I'm opting for a raspberry pi for connectivity, monitoring, safety and so on). I got it working about a month ago with some tools and hardware I borrowed from my dad but the problem there was... My dad's negligence, meaning all the tools and hardware were half dead. In any case I managed to cut out two pieces I needed for a different project(and see that it works after all). And I also plan on open sourcing it. though most of the code is written in Rust. With the exception of a small webserver for monitoring the process remotely(even visually with a tiny webcam) - no point in wasting so much effort on that and dealing with all the async-await-read-write locks that come along with it. The webserver mostly parses logs and makes system calls to binary files.
- mfi 5y ago
  That sounds like an amazing project! Please open-source it, I would love to read more about it :)
metal_am 5y ago
For anything CNC, there's no substitution for stiffness. And you're not going to get that with aluminum extrusions. Something like the PrintNC would be 1,000 times more capable due to using steel.
- jacquesm 5y ago
  Another reason why you don't want aluminum is due to the expansion as a function of temperature variation, which can be considerable over a longer run. But for this small size you can probably get away with that unless you start to move really fast, or have a head that generates a lot of heat.
- KennyBlanken 5y ago
  Preface: from your username I'm guessing you mightknow most of this, so my comment is for the benefit of non-machinist HNers. It depends. Also, to be more accurate, you need high modulus (vibration dampening) and strength. An extremely strong material that doesn't dampen vibration isn't helpful, for example. If you need to produce "Live Laugh Love" signs, you need enough stiffness and dampening that you can cut wood or plastic and have it look clean visually / need minimal post-processing before applying a finish, and do so quickly enough that your labor costs aren't high (never ever EVER leave hobbyist-level CNC machines unattended!) If you can do so with something approaching ideal chip load on the tool so you don't wear through them like crazy, even better (also you get more chips than dust, which is better for you, your dust collection system, etc.) Endmills work best when they take a nice bite out of whatever you're cutting; heat from cutting leaves with the chip. Too small a bite and you're just rubbing the workpiece, and the tool cutting edge isn't cutting, but getting polished smooth. If you need to produce accurate parts, you have to do spring and finish passes anyway (for those who don't know: even very stiff CNC machines still have flex in them. You do a rough cut at ideal chip load for your endmill, then one or more "small bite" follow-up passes where there is far less load on everything and thus the endmill face is closer to where it should be.) Since you're doing those passes to get your dimensions, machine "stiffness" mostly just lets you do it all faster. When it comes down to it, all you really need in a CNC machine in terms of "stiffness" is enough to let your endmill spend most of its time working at an ideal chip load without wandering all over the place. If the endmill's positioning changes too much with the machine flexing or vibrating, then one flute of the endmill could end up getting much more of a chunk to bite off than it should, and...snap. Beyond not destroying your endmills, more stiffness just lets you go faster. And like they say in the car world, speed costs money; how fast do you wanna go? Stiffness is not the only important factor; dampening is also important. That's why you see some epoxy-gravel composite builds. Lots of mass, very strong (the stone), very high dampening (the epoxy.) One of the unfortunate things about hobby-level CNCs is that they use palm router motors with extremely high spindle speed, but they're not terribly stiff, and most of them come with software that has rudimentary CAM path generation. The high spindle speed means that you have very little tolerance between the tool flute getting too little of a bite and too much of a bite, which is easy to do when the frame isn't very strong (and at high spindle speeds, vibration dampening starts to get very important, too.) Hobby-level CNCs benefit enormously from more advanced milling techniques like trochoidal milling, or "adaptive clearing", as Fusion 360 calls it (I think.) Trochoidal milling maintains tool load while optimizing for using as much of the side of the endmill as possible (spreading wear on more of the tool.) The machine appears to "nibble" away, instead of steaming along whatever profile is being cut. A simple profile on a weak frame machine means a very shallow depth of cut to keep forces low, but that means all of your cutting is being done by a very small portion of the endmill. They also benefit from having as slow a spindle speed as possible. There are speed controllers available to help reduce the speed of a palm router, which also lowers noise and reduces bearing and brush wear. I'm in kind of a rush so hopefully someone can correct or clarify where needed.
Wesxdz 5y ago
I'd love to have an open source CNC machine to design joinery with http://ma-la.com/tsugite.html http://ma-la.com/tsugite.html Ideally a whole house and most of the furniture... If anyone has any ideas on how to accelerate build times of open hardware, that's something I'm trying to solve. Creating high quality instructionals is a huge amount of work and I think instructionals should be automatically generated by computer vision and have interactable elements, ideally AR, but even just highlighting wiring diagrams on hovering would be hugely helpful. Even if things are well documented, replication is still insanely pyrrhic without economy of scale or universal fabrication. It's time consuming because it's hard to replicate knowledge/tool environments quickly.
- gunshai 5y ago
  I forwarded this to a structural engineer who specializes in timber design. That website you linked is really cool.
- mfi 5y ago
  I can't help you with ideas of how to accelerate build times of open hardware, but thank you so much for sharing that link. Looks really promising, will probably test it using the CNC-machine someday soon!
newintellectual 5y ago
Not to be too big of a critic, but ... This, and other projects like it, are NOT "from scratch". It doesn't include little things such as a motor; wires; other electronics; the metal frame. Until "consumer" 3D fabrication can do more serious fab than random weak structural plastic components, it will remain as a hobby. The industrial machines able to sinter metal into strong parts or using carbon fiber - those have serious practical utility. I'd be much more interested in a low cost, high precision metal sintering 3D printer than a project such as this.
avmich 5y ago
This - https://www.adambender.info/post/2017/03/25/epoxy-granite-machine-frame-how-to https://www.adambender.info/post/2017/03/25/epoxy-granite-ma... - could be a useful addition to the mill.
mayapugai 5y ago
Hey, this is a great project. I am working on a project that involves both hardware and software much like your CNC project. I especially like how the README.md is exquisitely well-written, complete with images. May I ask - did you manually link the pictures and links while writing the README or did you use a program that let you generate the source md file from a WYSIWYG editor? PS. I am a newbie here. So, I really hope this question isn't against the code of conduct here.
- primitivesuave 5y ago
  Your polite and inquisitive message exemplifies the code of conduct here :) Welcome!
- spdebbarma 5y ago
  There are a limited number of ways you can link your images on a Github README. The format is the same for all methods. ![image description](image.png) 1. You might upload to a bucket online and link them individually. ![image]https://cdn.bucket.url/image.png https://cdn.bucket.url/image.png) 2. Upload the images to your Github repo in a folder and relatively link them. ![image](./images/image.png) 3. Edit your README on the WYSIWYG editor on Github itself and paste the images using Ctrl+V. Github will automatically host and link the image in your file. I hope this has been helpful!
senectus1 5y ago
This is fantastic. I've been putting off buying a 3D printer but I've always wanted to get a CNC machine... this might push me over the edge. The idea of having end to end manufacturing capability on the desk is very very attractive. The things I could do with this combination... what a time to be alive.
malwrar 5y ago
Thanks for this guide! Just realized I have everything I need on-hand to follow your guide & wanted to comment and let you know I plan to follow it this weekend. Looking forward to it!
- 0des 5y ago
  Please post about this if you do, this project looks awesome. Though I don't have the parts on hand yet, I'm strongly considering building one as well.
  - malwrar 5y ago
    Totally will do, seems like a fun project to try making a youtube video around!
    - 0des 5y ago
      Indeed, what's your channel, if you don't mind me asking?
      - malwrar 5y ago
        I don’t actually have one loll, if I actually end up finishing this and editing it up I’ll post it to this one [1]. I’ve been meaning to try making videos for projects though, so I’ll try to make it interesting 1: https://m.youtube.com/channel/UCcP2O68iv1HZfWxK05jMkGA https://m.youtube.com/channel/UCcP2O68iv1HZfWxK05jMkGA
jrockway 5y ago
Does anyone have suggestions for making a CNC mill that's quiet enough to run in my apartment? I'm thinking about getting one of the cheap $250 Aliexpress specials (I only want to mill PCBs), but I'm guessing it's going to be too loud to run in a building where other people live. If I can make some performance tradeoff for relative quietness, I'd love to do it. (Maybe it's as simple as putting it in a foam enclosure or something? That sounds bad for spindle cooling, though.)
- kedikedi 5y ago
  Sound is one thing but also think of the dust, especially if you’re planning to machine pcb at your home. That’s not good stuff. But speaking of sound, some of it comes from the spindle. The faster it turns, the more noise it makes (usually). I was using a dremel as my spindle some time ago and it was veery noisy. Then I tried another machine that had a bigger spindle, that one was much quieter. Then there’s the sound of the material being processed. The cutting bit hits the material at spindle_speed*flute_count Hz. This also creates hell of a vibration. So you need to do two things: dampen the vibrations, and block the radiated noise. Plus you want to make sure you have some sort of dust control.
  - jrockway 5y ago
    That's a good point; the cutting itself is going to be noisy. I will have to rethink this project.
jzer0cool 5y ago
Slightly unrelated, I was curious if anyone here could recommend a 3d printer? Smaller one would be better just trying out now. Does not need to be too accurate (nice if it does) but looking for something that is budget and most for doing very flat 3d objects (ie: height no more than 1-2 inches, within a width/length much smaller than 10x10 cm)
- the_cat_kittles 5y ago
  the ender 3 is cheap and does everything i need
  - jzer0cool 5y ago
    thanks for your time to comment. this looks great. anything particular that might break down or any issues you had?
    - the_cat_kittles 5y ago
      not really. making sure the x and y belts are tensioned will improve your prints
- lsllc 5y ago
  Probably not what you are looking for, but if you can afford it, I can highly recommend the Prusa I3 MK3S+ (actually I have the MK3S, but it's pretty similar). The quality of the prints is incredible and the printer is really easy to use. I've printed a bunch of parts for use around the house that have solved problems where there's no way I could get a commercial solution -- I can just design what I want in Fusion 360 and print it. This was my first (and only!) 3D printer so I don't have any comparisons, but I have been tempted to get a Ender-3 (Pro) just as a comparison (although I don't really have the space for 2 3D printers). I did recently augment it with OctoPrint on a RPi with a touch screen (and of course a 3D printed front "console" that accommodated it) ... makes it much nicer to use and I can remotely manage via Wifi.
robinduckett 5y ago
I built myself a Mostly Printed CNC: https://docs.v1engineering.com/mpcnc/intro/ https://docs.v1engineering.com/mpcnc/intro/ It works really well, and as yet I have yet to kill it, for me that's a good metric.

462 points by mfi 5y ago

mfi 5y ago

I just finished my latest project, building a CNC-machine from scratch using an Arduino Uno, GRBL and 40x 3d-printed parts. It’s able to mill wood and aluminium, up to ~20mm thick. As with all my other projects, I think they should be executed in the open where other people can learn from my mistakes and get inspired to build their own things! Therefore I’ve spend a lot of time writing a free complete tutorial of the build, documenting every step with text and detailed images, creating a complete bill of materials (including STL-files for the 3d-printed parts) etc. I don’t want any dependencies on DIY-websites, so I’ve hosted it on GitHub, where anyone can clone it locally. I built this machine to gain more knowledge about mechanical engineering, electrical wiring, stepper motors, GRBL, CAD, CAM etc. Also, I guess I can build new fun things with the machine? Overly-engineered birdhouses maybe? Setup: * It’s running on an Arduino Uno, CNC-shield and GRBL. * 40 parts are 3d-printed (all the red parts in the video) * It’s based on Ivan Miranda’s blueprints, but I’ve adjusted some parts and structured the bill of materials. * It uses 2x 19:1 geared NEMA17 stepper motors for the Y-axis and 1x for the X-axis. The Z-axis is using a standard NEMA17 motor. * HTD5M belts and pulleys are used for X-axis and Y-axis. GT2 belt and pulleys are used for the Z-axis. If you have any questions, feel free to contact me. You’ll find my email in the top of the guide :)

billconan 5y ago
very cool! thanks for sharing. I don't have the equipments to drill holes on aluminum parts, I will probably need to use https://8020.net/ https://8020.net/ to build one.
- mfi 5y ago
  Aluminium is quite soft, so it might work if you have access to a screwdriver and a step drill
  - haliskerbas 5y ago
    I’m not an expert here but I’ve heard 8020 is expensive enough such that purchasing a drill press would probably be cheaper, if feasible, correct?
    - genewitch 5y ago
      There is also handheld drill press rigs that may be useful.
- arnado 5y ago
  You might also want to look at the mostly printed CNC, which uses standard conduit/pipe for the frame. https://docs.v1engineering.com/mpcnc/intro/ https://docs.v1engineering.com/mpcnc/intro/
  - AdamTReineke 5y ago
    Be warned these plans require you to drill a couple holes in the conduit. I managed with just a handheld drill though the holes weren't quite aligned. Definitely use a file or hacksaw to create a flat spot on the conduit where you want the hole so the drill bit doesn't wander as easily.
    - Nick87633 5y ago
      Or a center punch (helps on flat metal too). One favorite trick of mine is to print out 1:1 drill pattern drawings and center-punch through the paper onto my metal workpiece for all the drill locations. Fast and accurate.
      - dekhn 5y ago
        Basically, 2D printers (you know, those $150 things) are exceptionally high precision and accuracy tools for making 2D drawings. I've been using printers for years and it never occurred to me you could use it to print a (for example) 10cm square.
        jacquesm 5y ago
        You can if you are really nifty do limited scale PCB manufacturing this way. https://www.instructables.com/Creating-Printed-Circuit-Boards-with-a-INKJET-Prin/ https://www.instructables.com/Creating-Printed-Circuit-Board...
        sokoloff 5y ago
        Fusion360 seems to try to prevent you from exporting PDFs with the free hobbyist version. One tip that I discovered was to create a CUPS printer on a Linux VM that saves PDF files. (I found it printed slightly off sized if I sent a 2D drawing straight to the printer.)
- convolvatron 5y ago
  I use a cordless hand drill to drill and tap aluminum all the time (as does this project). adjust the speed until you are pulling out long ribbons instead of dust. you can use a little oil, but its not necessary. the only issue is trying to stay perpendicular to the work, but usually a little deflection doesn't matter. also pay attention to 'wowing', where instead of drilling your perfect round hole the drill bit starts to bounce around a triangle or pentagon and you end up making too big a hole. its often best to start with a pilot drill and then a final pass to clean it up. also its often easier to use a centering drill to setup the holes. it provides a pocket for the drill to rest in so that it doesn't wander, and you can use the centering drill to fine-tune the hole pattern before you make it permanent.
  - sokoloff 5y ago
    To easily stay perpendicular to the work, use a tap guide block. You can 3D print one or drill one out of stock on a reasonably square drill press.
- IgorPartola 5y ago
  I picked up a used drill press for $45 or $50 (I don’t remember now), and a tap and die set from Amazon for about $20. 10/10 would recommend if you have the space.
- 0des 5y ago
  Believe it or not, aluminum can be treated the same as wood when it comes to tools. Any drill that can drill wood can drill aluminum.
zwieback 5y ago
Awesome. Can it mill aluminum? If so, would you consider replacing some of the 3D printed parts with machined parts?
- mfi 5y ago
  Yeah it can! Ivan Miranda, the guy who has created the blueprints actually updated his machine with aluminium parts, milled on the CNC-machine. That might be something I'll do in the future!
  - jhgb 5y ago
    Von Neumann probe when?
    - jacquesm 5y ago
      Right after you figure out how to 3D print solid rocket fuel without things going 'bang' prematurely.
      - yetihehe 5y ago
        If you print Potassium Nitrate/Sorbitol[0] with direct granule extruder[1] you could do it. But this will probably need additional toolhead for engine body[2] (plastic-fiber composites DO have enough strength to survive using KNSB in engine, I've seen tests, but those are not publicly available) and for ceramic nozzle[3]. With some experimenting, probably doable. [0] http://www.nakka-rocketry.net/sorb.html http://www.nakka-rocketry.net/sorb.html [1] https://hackaday.io/project/181165-my-machinery-2021-direct-granules-extruder https://hackaday.io/project/181165-my-machinery-2021-direct-... [2] https://www.sciencedirect.com/science/article/pii/S2212827117307059 https://www.sciencedirect.com/science/article/pii/S221282711... [3] https://reprap.org/wiki/Ceramic_Extrusion https://reprap.org/wiki/Ceramic_Extrusion
eduardosalaz 5y ago
The CNC Shield is a blessing, shame the Gerber files aren't being published for newer versions.
- mfi 5y ago
  100%, it helps so much with the wiring.
- thawkins 5y ago
  https://www.pcbway.com/project/shareproject/CNC_Pro_Shield_V3_00.html https://www.pcbway.com/project/shareproject/CNC_Pro_Shield_V...
dekhn 5y ago
I understand you put thought and time into your approach and it was a hobby to learn more abotu the process (and thus you know about MPCNC but decided to make your own). I've also build similar systems and I've learned some timesaving tricks that have paid off in terms of hobbyist enjoyment. I really like buying the majority of the parts from a place like OPenBuildsPartStore, rahter than assembling frames from channel manually. Time/cost/quality tradeoff is hard to beat here. I strongly recommend switching to Grbl_Esp32 https://github.com/bdring/Grbl_Esp32 https://github.com/bdring/Grbl_Esp32 with external controllers (this board https://www.tindie.com/products/33366583/6-pack-universal-cnc-controller/ https://www.tindie.com/products/33366583/6-pack-universal-cn... with these plugins https://www.tindie.com/products/33366583/external-stepper-motor-driver-ver-11/ https://www.tindie.com/products/33366583/external-stepper-mo... and these controllers https://www.amazon.com/STEPPERONLINE-1-0-4-2A-20-50VDC-Micro-step-Resolutions/dp/B06Y5VPSFN https://www.amazon.com/STEPPERONLINE-1-0-4-2A-20-50VDC-Micro...). That's what I ended up with because tuning current using the little pots is dumb, and you want a TON of current going to those huge motors. ESP32 + Grbl has a bunch of nice features that aren't in plain old Uno GRBL. My system has high torque NEMA23 with no gears (same motor for all 3 axes), I can't see any situations where adding more torque to the X or Y axes using a smaller gearer stepper makes sense.
- giantg2 5y ago
  "I can't see any situations where adding more torque to the X or Y axes using a smaller gearer stepper makes sense." Generally agree. Torque is only needed to a specific threshold. If it requires a lot of torque, then that's probably a good sign to slow the movement down (for the sake of the machine's longevity).
  - jacquesm 5y ago
    On the contrary, plenty of tools need to move and chip otherwise they'll get dull, cutting speed is a function that increases a machines' longevity. But cutting speed does require a solid mechanical setup, drivers that can source some current and a drive train that does not suffer from over or undershoot ('slop').
roland35 5y ago
what material did you use for 3d printing? I would think PETG or ABS is probably best?
- mfi 5y ago
  I actually used normal PLA
  - naasking 5y ago
    PLA is actually the stiffest of those materials, just keep it cool enough that it doesn't warp! I expect that would only be a problem around the spindle which can get quite hot, and maybe stepper motor mounts.
- moepstar 5y ago
  You most definitely want to avoid PETG as it is pretty... flexible... PLA is the way (the MPCNC, for example, is designed with PLA in mind) in this case, as with ABS you most likely need higher printing temps, bed temps, an enclosure to keep even the slightest drafts out...
giantg2 5y ago
You mention aluminium. Any plans to add a lubricant sprayer?
2muchcoffeeman 5y ago
>I can build new fun things with the machine? Overly-engineered birdhouses maybe? I don’t have space for a workshop. I live in an apartment. So I’m pretty limited in the sorts of materials and tools I can use. 20mm of wood is probably quite useful. My table top and shelves aren’t 20mm thick. If this can go through MDF I’d say it’s really useful.
- dekhn 5y ago
  this sort of machine could easily carve 5-10mm of MDF in a single pass. It's awful loud though, even when enclosed. What I recently made: a terrain map of california cut into plywood. It's several feet by several feet (~600mmx600m), 0.75" (almost 19mm deep at the lowest points in california) and wall-mount-worthy.
  - te 5y ago
    Sounds really cool! Got pics?
- fuzzylightbulb 5y ago
  Unless you have an incredible dust collection system in place, I would seriously reconsider any potential plans to cut MDF in your apartment. The particles are very fine and you will find it everywhere. And that is to say nothing of the particles that you'd be inhaling.
jacquesm 5y ago
What a fantastic project. Is the design parametric, in other words, are there parts that would need to be scaled up to have larger x, y or z axis or are those all off the shelf and are the various STL files for the components the same if the design is scaled up?
- mfi 5y ago
  Glad you like it, most cred should go to Ivan Miranda for the core design, I just executed, updated some parts and wrote a guide around it :) No, it's not parametric in that way. But it is possible to extend the "mill-bed" by: * X-axis: Increase length of frame and bridge profiles. Buy longer MGN12H rails used for the X-axis. * Y-axis: Increase length of frame profiles. Buy longer MGN12H rails used for the X-axis. * Z-axis: Increase the vertical beams between lower and upper frame. Buying longer MGN12H rails used for the Z-axis and a longer acme rod.
aquaphile 5y ago
Nice work! You made a lot of great design choices. +1 to those that recommend upgrading your extrusions and motor mount on future iterations. The rigidity is well worth it. If you are ever deciding between belts and ballscrews, I recommend ballscrews. It is worth the extra $$. For the milling of aluminum, I suggest adding a compressed air nozzle. It will make a huge difference in milling AL. Also, some of the new bits are fantastic at hogging out aluminum. For reference see pic at https://drive.google.com/file/d/1BWvOOwmaQljwhdBzYNvilYDKdsyCkXeR/view?usp=sharing https://drive.google.com/file/d/1BWvOOwmaQljwhdBzYNvilYDKdsy... We built our own 5-axis CNC too, to do large envelope parts trimming. It looks like Frankenstein, but works pretty well. See a pic at https://drive.google.com/file/d/0Bydp4fsq-EhtUndOTlZTcU1fTEU/view?usp=sharing&resourcekey=0-rlUPDkgckiSJ5pKbqfnhNA https://drive.google.com/file/d/0Bydp4fsq-EhtUndOTlZTcU1fTEU.... We use it to trim the chassis parts for our baby car seats at https://kioma.us https://kioma.us Keep on building!

jaxn 5y ago

Really neat project! Maybe I missed it, but is there a general cost estimate anywhere? I saw the BoM, and assume most the cost is in the router and stepper motors, but is this like ~$500?

mfi 5y ago
Thanks! I think it spent around $1100 in total, but then I paid for fast shipment and ordered quite a lot of parts that I ended up not using. You can probably build it for $600-$1500, depending on where you source the parts, what quality you buy, speed of delivery etc.

cinntaile 5y ago

Do you know how accurate it is?

mfi 5y ago
I milled a test block in wood to check the accuracy, and it was sub-millimeter accurate. I can't measure further than that as my tools doesn't allow it. But I doubt that it's super accurate due to the 3d-printed parts, aluminium instead of steel etc.
- wolfram74 5y ago
  Being a spherical cow loving physicist, I still get caught off guard by what counts as "precise" in engineering contexts. Even when I'm making stuff in meat space I don't think I've ever bothered to intentionally get better than 1% relative precision.
  - sokoloff 5y ago
    For a framer, 1/8” is precise enough. For a finish carpenter, 1/32” is precise enough. For a 3D printer, 0.004” is precise enough. For a machinist, 0.0005” is precise enough.
    - curtain 5y ago
      0.004" is read as "four thou", and 0.0005" as "five tenths", as in five tenths of a thou, FWIW. I only picked up imperial thanks to binging This Old Tony videos.
      - sokoloff 5y ago
        If you enjoy https://www.youtube.com/c/ThisOldTony https://www.youtube.com/c/ThisOldTony, you might also enjoy https://www.youtube.com/c/Clough42 https://www.youtube.com/c/Clough42 https://www.youtube.com/c/Blondihacks https://www.youtube.com/c/Blondihacks and https://www.youtube.com/user/JohnGrimsmo https://www.youtube.com/user/JohnGrimsmo

j_walter 5y ago

Reminds me of the Root CNC project. https://rootcnc.com/ https://rootcnc.com/ Great work!

mfi 5y ago
Haven't seen this one before, thanks for sharing!
IgorPartola 5y ago
This looks great. I do love that MP-CNC tells me immediately the approximate cost. Wish more projects did that. I can’t tell if a Root 4 would cost me $200 or $2,000 without looking for all the parts individually.
- j_walter 5y ago
  I did look for the parts because I was interested in getting one made...however many of the parts still aren't ready to go (control side), but the hardware cost other than that was fairly reasonable in the $500-800 range depending on how big you were going to go and which motors you chose to use.

542458 5y ago

Nice! I built an older model MPCNC years ago, and was able to get pretty great results with it relative to the tiny cost and huge flex in the frame. I managed to cut some brass Christmas ornaments that I’m pretty proud of. I like that you’re using racks here - the belts on the MPCNC were a major weak point in my experience. I wonder if you could get away with 3D printed racks and pinions. There’s a lot of structural plastic in there already, would the hit from accuracy from using lesser racks make a difference?

bmsleight_ 5y ago
Love to see the brass Christmas ornaments have you a photo ?
metal_am 5y ago
You can buy ball screws somewhat cheaply direct from China. That'd be the way to go.

amelius 5y ago

Most hobby CNC projects have only 3 degrees of freedom, whereas most high-end commercial projects have a few DOFs more.

sokoloff 5y ago
3-axis mills are the most common configuration for commercial mills (probably by a wide margin).
thedingwing 5y ago
This is not true. 5 axis mills and 9+ DOF CNC mill/turn centers exist, and they are becoming more common, however 3 axis vertical mills are still the backbone of most machine shops.

rytis 5y ago

Great work!! What router bits are you using for milling wood and aluminium?

mfi 5y ago
Thanks! I'm still very new to the CNC-space, so I'm currently exploring different bits. So far I've only bought some low-cost flat end mills from Amazon, but I'll probably work my way up to higher quality when I've used it more.
dekhn 5y ago
carbide: https://www.amazon.com/gp/product/B0080CVUVS https://www.amazon.com/gp/product/B0080CVUVS as an example. it never dulls.

roland35 5y ago

Very cool! I am actually also making a 3d printed pen plotter! I love how easy it is to get common hardware like bearings, plus how nice it is to print parts on demand. Edit to add the link to the plotter: https://www.thingiverse.com/thing:2349232 https://www.thingiverse.com/thing:2349232

mfi 5y ago
Yeah, the 3d-printer is a game-changer in these type of DIY projects!

ElijahLynn 5y ago

The pictures on that README are insane! So HELPFUL! And, I already have that same Makita router so I am more tempted to try this... because of the pictures!

mfi 5y ago
Haha yeah, I spent quite a lot of time to document everything. I sometime have trouble following tutorials because they leave out things that are obvious to them, but not to the reader. So I've really tried to include every step in detail, even though they might be "simple" and obvious. What's stopping you? Go for it! :D

bartwe 5y ago

I recommend building a cnc, had a lot of fun building a mpcnc

phkahler 5y ago

Do any of these small CNCs support G02 and G03 for circular arcs? I was recently looking at G-code output from Solvespace and figure we need to update it to produce those codes rather than tiny linear segments. But will the home-built CNCs even support that?

Robotbeat 5y ago
I think Marlin supports it.
vvoid 5y ago
LinuxCNC will (http://linuxcnc.org/docs/2.8/html/gcode/g-code.html#gcode:g2-g3 http://linuxcnc.org/docs/2.8/html/gcode/g-code.html#gcode:g2...) - but your CAM may not. Edit: did not realize I was replying to solvespace, bring on the arcs!
- phkahler 5y ago
  >> Edit: did not realize I was replying to solvespace, bring on the arcs! There's a guy working on a g-code template right now. It should substitute the g-code into the template on export so it's machine ready. I'd like to get into all that, but I'm still working on construction tools and stuff.
opencl 5y ago
Most of the small hobbyist machines I've seen (including this one) use Grbl, and Grbl does support G02/G03.
dekhn 5y ago
grbl supports arcs and it represents the most common Gcode firmware on these "home-builts"

MayeulC 5y ago

This got me wondering: most CNCs and 3D printers use switches for calibration, plus stepper motors for positioning. Has anyone tried to use cameras or a Valve Lighthouse (0.3mm precision), maybe with accelerometers and encoders, for tracking? That would allow the use of cheaper, faster, torquier, more efficient DC motors, as well as release the accuracy constraints for a lot of parts (depending on which part is being tracked). The goal would be to trade hardware complexity and price for software complexity, since it's easier to re-purpose software (and something like lighthouse base stations has multiple uses, so the price could be shared between projects).

LeifCarrotson 5y ago
Yes and no: No, no one I'm aware of has tried using DC motors and cameras instead of steppers to control a printer. But yes, industry uses optical technology in large CNCs all the time. Some homing switches are physical clicky switches, some are inductive proximity sensors, but an optical 'horseshoe' througbeam/fiberoptic sensor is the standard for highly repeatable sensor-based homing. Depending on your control system, homing to a hard stop by measuring motor torque can also be highly effective, then you don't even need switches. I've personally worked on a number of CMMs (coordinate measuring machines, basically a CNC with a probe tip for checking that something was machined within tolerances instead of a spindle for actually cutting it) that use 90V DC motors and Heidehein glass scales for positioning. We calibrate them using laser interferometers; another optical technique - just with a single beam. Those same CMMs are being phased out across the industry in favor of optical measurement systems, just because they're faster. Shane of the excellent "Stuff Made Here" Youtube channel recently made a big CNC painting robot that did optical tracking for a coarse positioning stage and used steppers for the local stage: https://youtu.be/osUTMnDFV30 https://youtu.be/osUTMnDFV30
tupshin 5y ago
I think there's a very big future in adding more (optical and other) feedback mechanisms to CNC machines, but 0.3mm resolution is really only good enough for the crudest of devices. For comparison, a typical ball screw, has positioning accuracy/resolution of around .02mm

gtirloni 5y ago

What's 40x? I feel brain challenged today as I can't understand what that means in this context.

finder83 5y ago
I read it as "40 individual 3D printed parts."
wipash 5y ago
They mean 40 separate 3D printed parts: https://github.com/maxvfischer/DIY-CNC-machine/blob/main/BILLOFMATERIAL.md#3d-printed-parts https://github.com/maxvfischer/DIY-CNC-machine/blob/main/BIL...
- mfi 5y ago
  Exactly, I meant 40 unique 3d-printed parts

aidenn0 5y ago

Now we need someone to make a 3d-printer out of 40x CNC'd parts and we'll have a never-ending supply of both!

axegon_ 5y ago

Congratulations! I'm working on one in my spare time but I've decided to cram in as much features as possible(as far as not being able to cram all the features into an arduino or esp32 so ultimately I'm opting for a raspberry pi for connectivity, monitoring, safety and so on). I got it working about a month ago with some tools and hardware I borrowed from my dad but the problem there was... My dad's negligence, meaning all the tools and hardware were half dead. In any case I managed to cut out two pieces I needed for a different project(and see that it works after all). And I also plan on open sourcing it. though most of the code is written in Rust. With the exception of a small webserver for monitoring the process remotely(even visually with a tiny webcam) - no point in wasting so much effort on that and dealing with all the async-await-read-write locks that come along with it. The webserver mostly parses logs and makes system calls to binary files.

mfi 5y ago
That sounds like an amazing project! Please open-source it, I would love to read more about it :)

metal_am 5y ago

For anything CNC, there's no substitution for stiffness. And you're not going to get that with aluminum extrusions. Something like the PrintNC would be 1,000 times more capable due to using steel.

jacquesm 5y ago
Another reason why you don't want aluminum is due to the expansion as a function of temperature variation, which can be considerable over a longer run. But for this small size you can probably get away with that unless you start to move really fast, or have a head that generates a lot of heat.
KennyBlanken 5y ago
Preface: from your username I'm guessing you mightknow most of this, so my comment is for the benefit of non-machinist HNers. It depends. Also, to be more accurate, you need high modulus (vibration dampening) and strength. An extremely strong material that doesn't dampen vibration isn't helpful, for example. If you need to produce "Live Laugh Love" signs, you need enough stiffness and dampening that you can cut wood or plastic and have it look clean visually / need minimal post-processing before applying a finish, and do so quickly enough that your labor costs aren't high (never ever EVER leave hobbyist-level CNC machines unattended!) If you can do so with something approaching ideal chip load on the tool so you don't wear through them like crazy, even better (also you get more chips than dust, which is better for you, your dust collection system, etc.) Endmills work best when they take a nice bite out of whatever you're cutting; heat from cutting leaves with the chip. Too small a bite and you're just rubbing the workpiece, and the tool cutting edge isn't cutting, but getting polished smooth. If you need to produce accurate parts, you have to do spring and finish passes anyway (for those who don't know: even very stiff CNC machines still have flex in them. You do a rough cut at ideal chip load for your endmill, then one or more "small bite" follow-up passes where there is far less load on everything and thus the endmill face is closer to where it should be.) Since you're doing those passes to get your dimensions, machine "stiffness" mostly just lets you do it all faster. When it comes down to it, all you really need in a CNC machine in terms of "stiffness" is enough to let your endmill spend most of its time working at an ideal chip load without wandering all over the place. If the endmill's positioning changes too much with the machine flexing or vibrating, then one flute of the endmill could end up getting much more of a chunk to bite off than it should, and...snap. Beyond not destroying your endmills, more stiffness just lets you go faster. And like they say in the car world, speed costs money; how fast do you wanna go? Stiffness is not the only important factor; dampening is also important. That's why you see some epoxy-gravel composite builds. Lots of mass, very strong (the stone), very high dampening (the epoxy.) One of the unfortunate things about hobby-level CNCs is that they use palm router motors with extremely high spindle speed, but they're not terribly stiff, and most of them come with software that has rudimentary CAM path generation. The high spindle speed means that you have very little tolerance between the tool flute getting too little of a bite and too much of a bite, which is easy to do when the frame isn't very strong (and at high spindle speeds, vibration dampening starts to get very important, too.) Hobby-level CNCs benefit enormously from more advanced milling techniques like trochoidal milling, or "adaptive clearing", as Fusion 360 calls it (I think.) Trochoidal milling maintains tool load while optimizing for using as much of the side of the endmill as possible (spreading wear on more of the tool.) The machine appears to "nibble" away, instead of steaming along whatever profile is being cut. A simple profile on a weak frame machine means a very shallow depth of cut to keep forces low, but that means all of your cutting is being done by a very small portion of the endmill. They also benefit from having as slow a spindle speed as possible. There are speed controllers available to help reduce the speed of a palm router, which also lowers noise and reduces bearing and brush wear. I'm in kind of a rush so hopefully someone can correct or clarify where needed.

Wesxdz 5y ago

I'd love to have an open source CNC machine to design joinery with http://ma-la.com/tsugite.html http://ma-la.com/tsugite.html Ideally a whole house and most of the furniture... If anyone has any ideas on how to accelerate build times of open hardware, that's something I'm trying to solve. Creating high quality instructionals is a huge amount of work and I think instructionals should be automatically generated by computer vision and have interactable elements, ideally AR, but even just highlighting wiring diagrams on hovering would be hugely helpful. Even if things are well documented, replication is still insanely pyrrhic without economy of scale or universal fabrication. It's time consuming because it's hard to replicate knowledge/tool environments quickly.

gunshai 5y ago
I forwarded this to a structural engineer who specializes in timber design. That website you linked is really cool.
mfi 5y ago
I can't help you with ideas of how to accelerate build times of open hardware, but thank you so much for sharing that link. Looks really promising, will probably test it using the CNC-machine someday soon!

newintellectual 5y ago

Not to be too big of a critic, but ... This, and other projects like it, are NOT "from scratch". It doesn't include little things such as a motor; wires; other electronics; the metal frame. Until "consumer" 3D fabrication can do more serious fab than random weak structural plastic components, it will remain as a hobby. The industrial machines able to sinter metal into strong parts or using carbon fiber - those have serious practical utility. I'd be much more interested in a low cost, high precision metal sintering 3D printer than a project such as this.

avmich 5y ago

This - https://www.adambender.info/post/2017/03/25/epoxy-granite-machine-frame-how-to https://www.adambender.info/post/2017/03/25/epoxy-granite-ma... - could be a useful addition to the mill.

mayapugai 5y ago

Hey, this is a great project. I am working on a project that involves both hardware and software much like your CNC project. I especially like how the README.md is exquisitely well-written, complete with images. May I ask - did you manually link the pictures and links while writing the README or did you use a program that let you generate the source md file from a WYSIWYG editor? PS. I am a newbie here. So, I really hope this question isn't against the code of conduct here.

primitivesuave 5y ago
Your polite and inquisitive message exemplifies the code of conduct here :) Welcome!
spdebbarma 5y ago
There are a limited number of ways you can link your images on a Github README. The format is the same for all methods. ![image description](image.png) 1. You might upload to a bucket online and link them individually. ![image]https://cdn.bucket.url/image.png https://cdn.bucket.url/image.png) 2. Upload the images to your Github repo in a folder and relatively link them. ![image](./images/image.png) 3. Edit your README on the WYSIWYG editor on Github itself and paste the images using Ctrl+V. Github will automatically host and link the image in your file. I hope this has been helpful!

senectus1 5y ago

This is fantastic. I've been putting off buying a 3D printer but I've always wanted to get a CNC machine... this might push me over the edge. The idea of having end to end manufacturing capability on the desk is very very attractive. The things I could do with this combination... what a time to be alive.

malwrar 5y ago

Thanks for this guide! Just realized I have everything I need on-hand to follow your guide & wanted to comment and let you know I plan to follow it this weekend. Looking forward to it!

0des 5y ago
Please post about this if you do, this project looks awesome. Though I don't have the parts on hand yet, I'm strongly considering building one as well.
- malwrar 5y ago
  Totally will do, seems like a fun project to try making a youtube video around!
  - 0des 5y ago
    Indeed, what's your channel, if you don't mind me asking?
    - malwrar 5y ago
      I don’t actually have one loll, if I actually end up finishing this and editing it up I’ll post it to this one [1]. I’ve been meaning to try making videos for projects though, so I’ll try to make it interesting 1: https://m.youtube.com/channel/UCcP2O68iv1HZfWxK05jMkGA https://m.youtube.com/channel/UCcP2O68iv1HZfWxK05jMkGA

jrockway 5y ago

Does anyone have suggestions for making a CNC mill that's quiet enough to run in my apartment? I'm thinking about getting one of the cheap $250 Aliexpress specials (I only want to mill PCBs), but I'm guessing it's going to be too loud to run in a building where other people live. If I can make some performance tradeoff for relative quietness, I'd love to do it. (Maybe it's as simple as putting it in a foam enclosure or something? That sounds bad for spindle cooling, though.)

kedikedi 5y ago
Sound is one thing but also think of the dust, especially if you’re planning to machine pcb at your home. That’s not good stuff. But speaking of sound, some of it comes from the spindle. The faster it turns, the more noise it makes (usually). I was using a dremel as my spindle some time ago and it was veery noisy. Then I tried another machine that had a bigger spindle, that one was much quieter. Then there’s the sound of the material being processed. The cutting bit hits the material at spindle_speed*flute_count Hz. This also creates hell of a vibration. So you need to do two things: dampen the vibrations, and block the radiated noise. Plus you want to make sure you have some sort of dust control.
- jrockway 5y ago
  That's a good point; the cutting itself is going to be noisy. I will have to rethink this project.

jzer0cool 5y ago

Slightly unrelated, I was curious if anyone here could recommend a 3d printer? Smaller one would be better just trying out now. Does not need to be too accurate (nice if it does) but looking for something that is budget and most for doing very flat 3d objects (ie: height no more than 1-2 inches, within a width/length much smaller than 10x10 cm)

the_cat_kittles 5y ago
the ender 3 is cheap and does everything i need
- jzer0cool 5y ago
  thanks for your time to comment. this looks great. anything particular that might break down or any issues you had?
  - the_cat_kittles 5y ago
    not really. making sure the x and y belts are tensioned will improve your prints
lsllc 5y ago
Probably not what you are looking for, but if you can afford it, I can highly recommend the Prusa I3 MK3S+ (actually I have the MK3S, but it's pretty similar). The quality of the prints is incredible and the printer is really easy to use. I've printed a bunch of parts for use around the house that have solved problems where there's no way I could get a commercial solution -- I can just design what I want in Fusion 360 and print it. This was my first (and only!) 3D printer so I don't have any comparisons, but I have been tempted to get a Ender-3 (Pro) just as a comparison (although I don't really have the space for 2 3D printers). I did recently augment it with OctoPrint on a RPi with a touch screen (and of course a 3D printed front "console" that accommodated it) ... makes it much nicer to use and I can remotely manage via Wifi.

robinduckett 5y ago

I built myself a Mostly Printed CNC: https://docs.v1engineering.com/mpcnc/intro/ https://docs.v1engineering.com/mpcnc/intro/ It works really well, and as yet I have yet to kill it, for me that's a good metric.