Resurrecting my OpenBuilds Ox CNC router

Hello everyone, it has been quite a while since I have posted anything here.

I have an OpenBuilds Ox CNC router that I built a few years ago (~May 2015, I think) along with a TinyG v8 controller board to drive it. It was always painful to get it to finish a job because it always had halting issues. If it weren’t for me storing the offsets from home I would never have completed any jobs with it. Really, I only ever finished one or two small jobs on it.

Well, the pandemic hit and with it came remodeling my house, which led to the garage getting stuffed. I have finally dug myself out of that hole and can even park my car in the garage. I built a couple of workbenches out of all of the scrap I had, and then created a permanent home for the Ox in the back corner.

Then I tried getting it going again. I have an old PC running Linux Mint and using CNC.js, which is what I was using before (except it was running Windows 7 before). Note that yes, I tried Chilipeppr, but it had other problems, like spawning a process then using the browser which had memory limitations, and halting issues, which lead me to CNC.js, which I have been quite happy with—except for the same job halting issues.

But, just like before, I am still getting strange behavior. I thought it might be a shielding problem, so I bought more shielded cable, only to find I had already checked that issue off my list years ago (it has shielded cabling, and a high-quality USB cable with a ferrite core).

Then, I went looking for configuration information on the TinyG v8, only to realize that this thing is pretty much done—nobody is really working on it anymore, and support is pretty much DIY.

Soooo…I’m looking for a new motion control system that will drive the 4 big NEMA23 steppers on this thing.

I see that OpenBuilds has a BlackBox Motion Control System X32 based on a 32-bit ARM CPU, which pairs with their own cross-platform control software, OpenBuilds Control. I downloaded and installed it on my Linux PC and it seems very much like CNC.js in that it has a lot of the same controls available. So, it seems like this would take a lot of the guesswork out of getting my Ox CNC back up and running. I also like that they have their own CAM software, too, OpenBuilds CAM. Although I haven’t tried it, it is comforting to know there is a one-stop shop for the motion controller hardware, controller software, and CAM software. If I can get it working with that, then maybe I’ll consider moving up to the more expensive CAM software, like VCarve or Aspire—but not before.

But, I have not seen much in the way of reviews of this controller, so I’m wondering if anybody here has tried it out?

Alternatively, is there any other system folks here would recommend for my OpenBuilds Ox CNC router?

(and thanks for reading this far—I just realized how much I typed)

BlackBox Motion Control System X32 (motion control hardware):

OpenBuilds Control (cross-platform host control software, Windows, Mac, Linux):

OpenBuilds CAM (a web-based application for converting SVG, DXF and Bitmap drawings, to GCODE for use with your CNC, Laser, Plasma or Dragknife Machine.): (looks like it has 4 g-code outputs, including Generic GRBL)

1 Like

Welcome back.
I don’t have any help for you on the new controller/software but I’m watching this post.

I need to dust off my CNC (openbuilds vintage) and move it to a new toolchain.

I am trying out FreeCad and UGS.

1 Like

@donkjr Which OpenBuilds CNC router did you build? Also, curious about what spindle you use. I use a quiet cut spindle with speed control that tops out at about 10k RPM.

I have what started life as an oversized OX (1 x 1.5M). Then @Eclsnowman cut me new, larger plates that support a C-beam gantry, which I reverse-engineered from something that had been exported from sketchup, and I switched to an interdigitated belt layout. I also switched from a 600W (IIRC) air-cooled spindle to a 1.5kW water-cooled spindle.

I kind of quit using my router when it flaked out and went plowing through a piece of baltic birch, to my dismay, and I changed my project focus for a while, learning more manual machining skills for a while.

But now that I have LinuxCNC working on my CNC mill, I’m vaguely planning sometime in the next few months to re-route some wires to keep my three-phase router spindle wiring better isolated from limit switches, and switch to using LinuxCNC on the router as well. A few projects have started piling up and it’s about time to kick them off again.

So that doesn’t help you now, but figured I’d mention my plans in case it’s useful.

1 Like

@mcdanlj It sounds like you have LinuxCNC running on a PC, and that is what you use to drive your mill? I’m curious–what control board and stepper drivers do you use?

EDIT: Part of the reason I ask is because I’ve been aware of LinuxCNC for a while, but it has always sounded like a beast to configure, so I’ve shied away from it.

Wait…what? Do you have a CoreXY layout on your router, or is this something else?

BTW, I recall you are the K40 guru. Mine has been sitting idle in my garage for a few years now (unused since pre-pandemic). Assuming my laser tube is even still functional (my understanding is they slowly leak/degrade over time whether you’re using them or not), then you may see me pinging you about that. :grinning:

On the mill, I’m running Linux on a Raspberry Pi 4, external stepper drivers, and a control board that is supported by Remora. I have a 36V power supply, which is stepped down to 12V for the control board which feeds the RPi with 5V, and I have a touch screen attached for mill control. I have it basically working but am still tuning it, and planning to add more hardware. Probes and air control at least. I can’t easily add spindle speed control as it is, but I might gut the head and put a high-speed spindle inside instead.

LinuxCNC does take some work to get going. Remora has some sample configurations that were some help getting started, but I discovered through a little frustration that you really do have to look up what every line means in the LinuxCNC documentation and make appropriate changes. :smiling_face:

No, CoreXY wouldn’t have a reason to be interdigitated.

This is the “Everman” arrangement:

1 Like

@mcdanlj Oh wow! That looks a lot like rack and pinion, but using belts! Nifty idea!

We have lots of K40 experts on here and we are all ready to help if needed.

My K40 has been idle for a couple of years :grimacing:. Not sure I will ever power it on again. Not sure what to do with it as I am in the process of building a laser diode unit.

I don’t remember the model, I built it from a kit.
The spindle is an 800w DC air-cooled.
The controller is Tiny G.
I was running Fusion 360 => Chillipeper

@donkjr That looks pretty much identical to my OpenBuilds Ox, except you have really nice cable connectors and your cable routing looks a bit better, too, and I have the drag chain on the other side. Oh, and it looks like you made your own acrylic mount for the spindle speed controller. Even the size looks the same. I opted for the black extrusions. I started out with Chilipeppr, too.

Did you ever have any halting issues?

@donkjr If I can get the Ox control figured out, I’ve been thinking of mounting a relatively high wattage diode laser on it. But I’m not going there until/unless I can get the Ox motion working without halting issues.

Another motion control option seems to be the Buildbotics Controller, which they have even shown it to work on an OpenBuilds Ox.

The rapids look amazing! It includes a Raspberry Pi and is an all-in-one solution that does not need a computer. The stepper drivers (TI DRV8711) seem to be really good, too.

It seems a bit pricey though (I’m not saying it’s not worth it, but still). I wonder if anybody here has any feedback on this one?

Well, while the BuildBotics one looks good, at $699.99 vs. $239.99 for the BlackBox, I could probably buy a diode laser with the money saved. I think I’m going to pull the trigger on the BlackBox Motion Control System X32.

The only issue I have with the machine is it does not run the correct programmed spindle speed. The spindle drive does not reproduce the PWM correctly (another project on the bench) so I fudge it in Fusion.

Do you know why it halts … any errors posted?

@donkjr I already pulled the trigger on the BlackBox Motion Control System X32, but it hasn’t arrived yet.

The halting errors always seemed to only happen after the spindle activated. It is still hooked up to the TinyG. I will take a quick look at it and see what errors show up in the console, if any. It always seemed to hang the console, too, but perhaps there are some error message(s). It has been a while, but IIRC it was inconsistent. I’ll try to take a look before I hook up the new stuff and post a reply here.

Can’t go wrong with the BlackBox. Great customer support. I have the original from several years ago still going strong on my lathe.


The spindle current is very noisy. Do not run it near any control wiring.
That is why my driver is mounted on the gantry. The motor leads are short and are away from any control signals.

@donkjr I used to have it on the gantry, too. I moved it off when I was having similar problems. Also, yesterday I tried doing stuff and now the x-axis is having problems that seem like not all the coil wires are connected, but they are. The terminal mounts on the board seem a bit wobbly. I think my TinyG is just done. As I said, I’ve already bought the BlackBox X32, so I don’t think I’m going to spend any more time on the TinyG.