Hello this is my first post in Maker Forums.
I’m interested in purchasing a CNC milling machine (Probably a smallish Desktop type router)
Maybe a good first question is are there classifieds section here that I didn’t notice where I could maybe buy something second hand from a member?
If there aren’t classifieds here my next (many questions) will be those who’s questions can help me decide on a brand/model to purchase or if I should consider a DIY build.
Thanks
I’ve seen quite a few cnc routers on Facebook Marketplace. Everyone has their favorite brand. I always tell people to look for supported linear rails, antibacklash screws, and a rigid frame. I built my own from hardware store materials about 20 years ago. These days there is a lot more available for less of an investment. You should consider buying your second machine first. Get the most you can afford. The hard part is the CAD/CAM learning curve. For the money, I like the CNC4Newbies new carve.
1,400 is is outside my budget for a frame kit.
I’m interested in a 4080 size ideally is perfect to start with.
I have checked FB Marketplace. I live near a medium sized metropolitan area but what I’ve seen mostly are 4x8 foot tables and the smaller routers it seems like people selling them are trying to recover almost what they paid for a CNC that’s several years old.
If there isn’t a classifieds here can I make a wanted ad? Would that be ok?
I don’t know as I’m new here. LOL. For discussions sake, I have a 3018 all metal version, and it’s pretty decent, but too small for most things. The brass nuts are noisy as all heck.
Welcome to Maker Forums!
Nope! This site runs for free, and we don’t want to become a marketplace. Sorry, neither FS nor WTB.
Some other sites have a marketplace only for paid members as a perk to get people to pay, but we don’t have paid membership at all. Besides running as a completely free site, there’s way too much online scamming going on, and as soon as we allow a marketplace, someone is going to come after us because a deal went sour.
So we just don’t do it.
There are posts here on things people have done to improve small routers like the 4080 class, though. Making them stiffer, improving spindles, etc. That’s really what we’re here for.
Hi Michael I totally understand. I was on FB Marketplace a bit more and saw a kit for sale. Intrigued I looked into the type. It’s a Print NC it’s called. Looks really quality for the price. All Linear Rails, ball screws, good size stepper motors, liquid cooled spindle, rigid steel tube frame customizable in size.
I’m not sure if the FB seller still has the kit but I messaged.
Even if the kit from FB is gone I think this maybe a router I’m still gonna be looking at.
I’ll check on the forum with a search to see if there are any Print NC threads.
I’ve heard good reports of PrintNC. It is among the things I’d personally consider if I were starting out.
Of course it depends on the person who made it, but if the components are good and you end up having to replace some plastic pieces, it’s not terrible?
There is a list of machines at:
(ob. discl., I work for a company which makes 5 machines on that list)
Buying locally means saving on shipping, and having the chance to see the machine in operation to verify functionality, but it also means one is at the mercy of what comes up for sale.
Look into maintenance/availability of parts, software, &c.
I asked the seller of the PrintNC if he could do better than his posted price of 1,200$ he said he was pretty firm on the price. A problem was he is around 400mi away and thinks shipping would be costly at 200lbs and numerous boxes.
I found another producer of PrintNC Kits that have CNC milled parts instead of printed ones and uses Stainless for the frame. Lead time is up to a month and another month for shipping via sea freight. I may want one of them at a later point or DIY from parts.
I found another CNC very close to me. It’s a Chinese made 4030 or 6040 I think. One of the heavier duty models that can do metal the spindle isn’t water cooled but it looks like a 500w or so and has a Buildbotics controller (not sure what that is ATM) but I’ll look into it. I’m going to see if I can go check it out in the next few days.
I looked at the reddit link briefly. I understand the idea of “buying my second CNC first” and also the saying “you build you’re second CNC with you’re first”
I may just want to get a cheap 4040 to start. My first projects will be producing RC Airplane parts from Balsa wood, Light Plywood, thin fiberglass/carbon sheet and up-cycled aluminum beverage can aluminum and polystyrene foam.
A the second “category” of parts I want to make are custom bicycle parts specifically Fork Triple Tree clamps and moving into engine parts and things like wheel hubs etc.
I would like a lighter duty 4080 for the RC plane stuff.
A separate machine for the heavier metal parts. That could be a 6040 or even smaller probably with a 4th axis.
Another would be a good size machine like the PrintNC to make furniture. I could go to a local Maker Space for that though and likely would at least to start those projects.
After that would want something that can do large metal parts like a decent size industrial machine.
I don’t know if I mentioned but I did operate a CNC back around 2014. It was at a former Maker Space I was a member of. I think the machine was a DIY 4x8’ plywood machine. They overheated a spindle and I waited for it to be fixed. They got a new spindle but left the cooling system unchanged. I forget what I did but I somehow fixed the overheating issue before they let it happen again.
I think the software was called Dolphin?
My first project was a mock paramotor propeller from a scrap 2x4. It actually was really nice with the exception that I assumed the machine had a precision axis/level bed and didn’t adjust part levelness for the second side cut and one blade was thicker than the other.
Anyway I know there will be a good bit for me to learn even on a small inexpensive machine but I’m pretty sure I’ll learn quickly. I got into 3DP at the same time then bought my first printer about 5 years ago and have been printing kind of a bunch since.
I’ve used a Laser and picked that up in approximately 2 weeks including SVG production in Inkscape.
I imagine 3D CNC will be closer to 3D printing than Laser operation in the learning complexity.
I just looked into the Buildbotics controller. It looks pretty nice. It’s not a vaporware thing, still being sold. The guy is asking half of what a new Buildbotics controller costs alone.
Having a background in printing and such, You “may” want to investigate assembling your own machine using parts and extrusion available on the net. Openbuilds (which is closing its doors) kind of took over the parts as Inventables got out of that aspect of the hobby. Amazon and ebay via a lot of Chinese vendors can ship you the extrusion, plates, leadscrews, nuts, wheels, etc to roll your own. In doing this, I’m assembling a machine tailored to my work area and area of interest. It’s a c beam machine, 500y x 1000X for side loading that won’t take up as much as my current 1000x1000 X- carve. I work in a 12’x 14’ shed.
It’s like an adult erector set. I started with a Shapeoko2, upgraded to current x carve specs plus put in stiffeners, risers, 9mm belts, an aftermarket cnc4newbies Zaxis, and a t slot and basswood table. This machine is quite capable.
I’m probably gonna go the route of buying my first CNC to build my second one.
I’m scheduled to check out the CNC I found on Craigslist on Monday. 3040 or 4060 with Buildbotics controller.
I’m planning on asking the guy to let me plug it in to verify electronics function. Should I ask to mill a piece of hardwood or something to see if the spindle bearings are good or is there anything else I should be checking out?
It’s got a separate power supply for the spindle. I think it’s probably a good start and parts that can be reused or the mill upgraded later to flood coolant, water cooled bigger spindle, 4th axis etc.
I’ve got a lot to learn about tool path generation, fixturing best practices etc, too and I know that.
I see there are a lot of control firmware compared to 3D printing.
With 3D printing it’s basically Marlin or Klipper.
CNC appears to have many more from what I’ve seen initially.
I just watched a video by teaching tech on YouTube where Michael recommends kiri moto.
It was a basics video and honestly it looks considerably less involved than 3DP. I see that feeds, speeds and mill selection considerations for various materials are going to be the main things to consider it looks like.
This looks interesting.
I thought i was pretty well up on open source controllers but this is new to me.
Anyway, if it is included with the machine think it has all the tools you need. It has a atxmega based controller plus a pi running a web based controller.
I’m curious about it, the firmware appears to be written from scratch, rather than a marlin or klipper clone. Similar with the RASPi tool chain.
Pcb design is in KiCad 
There’s a lot of overlap; 3D printing is a form of CNC too. What you are looking at is a CNC router but anything where the computer controls movement is CNC something.
There are several more for 3D printing; Smoothieware, Repetier, RepRapFirmware, LinuxCNC, Kalico, and some proprietary ones.
Similarly, in the hobby CNC machining world, there are a few very common firmwares, and then a world of many others. There are multiple derivatives of Grbl including some that barely resemble the original, of which FluidNC and GrblHAL are probably most common. (In 3D printing, Marlin is also a Grbl derivative.) Then you have LinuxCNC, of which MachineKit was a derivative made when LinuxCNC only supported x86 machines, but now that work has gone back to LinuxCNC. Smoothieware is also commonly used in general CNC.
Grbl derivatives are common and easy to configure. LinuxCNC has tremendous power and configuring it is practically a hobby of its own. 
I will note that the LinuxCNC codebase is notorious for being “brittle” and the developers are reportedly quite insular and unwilling to accept more than the briefest of patches.
A fork of it, which was a total re-write for modularity and which focused on running on only the Raspberry Pi would be a very interesting, and I believe worthwhile project.
Ok yeah I think I was associating “CNC” with milling as a legacy term. I do know of the other firmware like repetier (Duet 3D boards use that I think) yeah Marlin an Klipper are just the main ones.
I wasn’t aware of Linux CNC though.
Doesn’t sound like a good choice for a beginner.
I wouldn’t know what to do with bugs or broken features.
An acquaintance of mine knows how to make custom Marlin Firmware and I’m running one he sent me on one of my printers currently. It doesn’t look extremely difficult in many ways but can have intricacies related to hardware, specifically configuration for particular screens and boards.
If I get into writing code it will be for 3D Printing Slicers to start so I’ll leave firmware coding for milling machines to people that know more about that than me (which is basically 0)
A “stand alone” VFD Inverter for the 500w air cooled spindle and the Buildbotics Controller are included.
I think the VFD was probably purchased with the intent of upgrading the spindle to a larger size but the owner didn’t do that?
Room for upgrading and the type of machine itself are still around 4-500 by themselves.
It’s probably the same unit pictured above from ChinaCNCZone. 3040 500w air-cooled spindle but with BuildBotics aftermarket controller and spindle power supply/controller.
For a CNC router, any grbl variant is probably fine, and it’s a great starting point.
If you want to do more, Smoothieware (on a compatible board) or LinuxCNC are probably the most mainstream options.
I run my mill on LinuxCNC, and just getting it to mostly set up has been a bit of a chore. But it has lots more features and has the ability to grow to basically anything you want to throw at it; it’s used commercially as well as in hobby machines.
It’s not just size. A VFD is for a three-phase spindle. They don’t have brushes and are generally quieter. And they will generally cost more and be heavier.
I picked up the CNC I mentioned paid 220.00 for it and a bit of gas money to coworker that took me to pick it up.
The seller included a bunch of collets and a number of endmills two of them are nice looking 1/4" carbide tools.
I didn’t ask how many hours it has on it but he only used it for wood. I didn’t power it on because he said they were experiencing a power outage where he was. He said if it didn’t work he would give me a refund.
The VFD included is new. He said he never used it. Probably got it with the intent of putting a bigger spindle on and didn’t.
Hopefully it’s endmill bearings are in good shape but I imagine those can be replaced if not?
That’s the only thing I could imagine could be an issue but I’ll see about running it in the next few days.
