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Best CNC Controllers [2023] for Mills, Lathes, and Plasma



John Abraham
Hey I'm John. I write about Manufacturing, Metalworking, CNCs and Lasers at Mellowpine. If you have any questions related to CNCs or Lasers, I'd be happy to answer them. Reach me at mail@mellowpine.com


Best CNC Controllers

The world of CNC Controllers has evolved considerably in the last two decades.

While industrial CNC controllers were the only choice a decade ago, new technological advancements have revolutionized the hobby CNC space.

Many features which were available only in industrial-grade CNCs are now available in hobbyist controllers too at an affordable price.

In this guide, I list the best CNC controllers available today for non-industrial CNC applications and provide a general review of each motion controller.

Some of these control systems are PC-based motion controllers that turn the PC/Computer into a controller while others depend on a microcontroller to interpret the G-code.

Even for control systems that turn the PC into the controller (Mach3, LinuxCNC), there are dedicated CNC controller boards that do a better job than the direct parallel port.

I have chosen the best dedicated external controller for those control systems.

This article will also serve as a CNC controller board comparison guide for those overwhelmed by the choices available.

MellowPine is reader-supported. When you buy through links on my site, I may earn an affiliate commission at no extra cost to you.

Best ControllerController Type
1RATTM motorGRBL CNC Controller
2Openbuilds BlackBox X32GRBL CNC Controller
3xPRO v5GRBL CNC Controller
4Ethernet SmoothStepper (ESS)Mach3/Mach4 CNC Controller
5Buildbotics CNC ControllerRaspberry Pi CNC Controller
6Mesa 7I76ELinuxCNC Controller
7UC100UCCNC Controller
8Mk3/4 USB ControllerPlanetCNC Controller
9Acorn CNC ControllerCentroid CNC Controller
10Masso G3Masso CNC Controller
Best CNC Controllers [2023]

Since the focus of this guide is on non-industrial CNC controllers, brands like Siemens, Fanuc and Pathpilot are avoided.

Many of these controllers can be used for several types of CNC machines and not just CNC mills.

*To find the exact price of these controllers, visit the seller’s website.

1. RATTM Motor 3 Axis CNC Controller- GRBL 1.1 – Best Affordable GRBL CNC Controller

RATTM Motor GRBL CNC Controller
RATTM Motor GRBL Controller

The RATTM Motor 3-axis GRBL CNC controller is a good value option for CNC engravers and laser engravers.

It is compatible with Universal Gcode Sender (UGS) and can run GRBL 1.1.

GRBL is an open-source CNC control platform/firmware that’s highly popular for running hobbyist CNC mills and desktop CNC routers.

RATTM Motor operates at a voltage of 12-24V but is recommended to run at 24V.

The driving voltage is 12V with a maximum current of 2A, making it suitable for NEMA 17 or smaller motors but not ideal for larger NEMA 23/24 motors.

If you want to run such powerful stepper motors, look into the Premium CNC GRBL controllers at the end of this list of controllers.

The controller supports a spindle of 24V with a 2A current and has improved spindle drive capabilities, supporting CNC spindles with RPMs up to 20,000.

RATTM Motor has an offline recognition mode and a USB interface and is compatible with Windows XP/7/8/10.

It has PWM control for the laser and spindle and is powered by an Arduino Nano (Atmel 328P) microcontroller.

RATTM Motor 3-axis GRBL CNC controller is a good choice for those seeking a budget-friendly controller with good performance.

RATTM Motor 3 Axis CNC Controller- GRBL 1.1
  • ♞【Model】Upgraded 3 Axis GRBL 1.1F USB Port GRBL Control Board; Input voltage: 24VDC
  • ♞【Support software】GRBL Contol/Candle(3 axis)/Universal Gcode Sender; Support System: Windows XP/7/8/10

Note: RATTM Motor also offers it as a bundled buy with an offline controller –RATTM Motor GRBL Control Board and Offline Controller.

2. Openbuilds BlackBox CNC Controller X32 – Best Premium GRBL CNC Controller

Openbuilds BlackBox CNC Controller X32
Openbuilds BlackBox CNC Controller X32
FeaturesBlackBox CNC Controller
Number of Axes4
Axis slave?Yes
Stepper drivers included?Yes
Microcontroller32-bit ATMega328p
Supported firmwareGrblHAL

BlackBox CNC Controller

Openbuilds has recently bought out a new version of the BlackBox Motion Control System.

It is one of the best GRBL-based CNC controllers available today.

It has a 32-bit processor, providing better performance, and supports modern machine attachments like rotary, air assist, coolant, etc.

Also, the true 4th axis capability of X32 is a considerable improvement from their older model.

In terms of connectivity, X32 supports WiFi, USB, SD, Bluetooth, and OpenBuild’s proprietary Xtension system.

X32 supports the GrblHAL firmware, which can be easily ported with new microcontrollers without having any knowledge of GRBL Core.

The controller integrates well with the GRBL interface software (free) by Openbuilds- Openbuilds Control.

Openbuilds Control can send the G-code to the controller, and you don’t need to use UGS or anything else.

Another really useful thing about the Blackbox is that you can use the Openbuilds INTERFACE touch offline controller.

Probably the best offline controller for any GRBL controller, INTERFACE lets you do almost anything without having to connect a computer to it.

The INTERFACE controller has to be brought separately, though, for around $190.

If these features matter to you, you can opt for BlackBox. It is a more mature, well-established product with good community support.

Almost any question you might have while using the BlackBox has probably been answered at the Openbuilds forum already.

Having the support of an online community of users who have the same device is invaluable, especially if you are a beginner.

It has better documentation, supports advanced firmware, and has better offline capability and connectivity.

BlackBox also has the advantage of being a part of the Openbuilds ecosystem, where you have CNC machine kits, accessories, and several other things which are naturally compatible with the BlackBox.

BlackBox Motion Control System X32 is an excellent pick for a high-quality motion control solution.

Openbuilds offers a one-year warranty on the BlackBox controller.

3. Spark Concepts-xPRO V5 CNC Controller

Spark Concepts xPRO V5
Spark Concepts xPRO V5
FeaturesxPRO V5 CNC Controller
Number of Axes4
Axis slave?Yes
Stepper drivers included?Yes
Microcontroller32-bit ESP32 
Supported firmwareGRBL_ESP32

xPRO V5 CNC Controller

xPRO v5 is another new and highly rated GRBL-based controller.

This controller has a 32-bit microcontroller at its core and that results in some major advantages over a controller with 8-bit microprocessors.

The 32-bit microcontroller gives the xPRO v5 much higher memory and processing power compared to 8-bit systems.

Most importantly, xPRO v5 can communicate with the computer via WiFi or Bluetooth whereas 8-bit GRBL controllers have a USB connection.

Having WiFi support, cable management is considerably reduced and you are not restricted by the wire length.

Also, you can control the xPRO v5 using even your phone through WiFi.

The stepper drivers on this controller are four Trinamic TMC5160 stepper drivers which can supply a current of up to 6A.

Unlike BlackBox, the xPRO v5 is a true 4-axis controller (XYZA).

This means it can control a rotary axis in addition to the X, Y, and Z axes.

The firmware on this controller is GRBL_ESP32 which is a 32-bit port of GRBL. This firmware is quite popular and frequently updated on GitHub.

You can connect up to 2 stepper motors on each axis of the CNC using the xPRO V5 and that means it can run up to 8 stepper motors at the same time.

xPRO v5 is manufactured and sold by Spark Concepts, which is based in Waynesville, OH.

One disadvantage of xPRO v5 compared to BlackBox is that it has no dedicated online community and GitHub is the only place where you can ask questions.

Spark concepts have excellent documentation on this controller on its GitHub page.

One disadvantage of this controller is that the manufacturer does not offer any formal warranty on it.

However, the general feedback on this controller is highly positive and almost everyone who has bought this controller is satisfied with its performance.

Overall, it is probably the best 32-bit GRBL controller on the market and an excellent choice for hobbyists wanting the best performance.

If you want a more detailed comparison between the BlackBox Controller and xPRO V5, you can read this- xPRO V5 vs Blackbox.

4. Ethernet SmoothStepper (ESS) – Best Mach3/Mach4 CNC Controller

Ethernet Smoothstepper
Ethernet SmoothStepper
FeaturesEthernet SmoothStepper
Number of Axes6
Axis Slave?Yes
Stepper drivers included?No
MicrocontrollerIt uses the processing power of the computer
Supported firmwareESS’s FPGA firmware
Price Check Price on Amazon

Ethernet SmoothStepper CNC Motion Controller

Manufactured by Warp9 Tech Design, this motion controller makes operating CNCs running Mach software easy and efficient.

Mach3 is the most popular controller software after GRBL for running hobbyist CNCs.

Although the makers of Mach3 have released a new version, Mach4, the earlier version still remains popular.

The most popular and reliable choice for running a Mach3/Mach4-based CNC is the Ethernet SmoothStepper (ESS).

Mach3 and Mach4 work by turning the computer itself into a CNC controller instead of relying on microprocessors.

You can run your CNC with Mach3/Mach4 by directly connecting the circuit (stepper drivers/breakout board) to the parallel port on your computer.

The other option is to use a dedicated motion controller like Ethernet SmoothStepper (ESS), which will act as an intermediary between the circuit and the computer.

ESS works with both Mach3 and Mach4.

For setting up Mach3/Mach4 to work with ESS, you need to install a plugin called Mach SmoothStepper plugin.

The plugin installation is straightforward and the video tutorials (and documentation) by Warp9tech should help you do it easily.

You need to use a 5VDC external power supply to power the ESS controller.

ESS costs $199 to buy from Warp 9 Tech Design’s website.

Ethernet Smoothstepper
Ethernet SmoothStepper

How ESS works

When supplied with G-code from the CAM software, Mach3/Mach4 converts the G-code to low-level commands.

These low-level commands are sent to ESS by the Mach SmoothStepper plugin.

ESS then generates the step and direction signals which are sent to the stepper drivers.

Using Ethernet SmoothStepper vs direct parallel port connection

There are significant benefits to using a dedicated controller instead of directly connecting to the computer via a parallel port.

Performance is significantly smoother when using ethernet SmoothStepper compared to direct connection with a PC.

This is due to smooth and stable pulse generation which results in a smooth motion of the stepper motors.

Without a dedicated controller like ESS, you need a parallel port in your computer for the connection.

ESS connects to the computer via an ethernet cable and connects to the stepper driver or breakout board via a parallel port.

mach3 UI
mach3 UI

Since the controller connects via an ethernet cable, the computer used is fully isolated from spikes in current. This is a real danger if you directly connect to your computer via a parallel port.

With a direct parallel port connection, if you do other work on your computer while the CNC is running, you risk missed steps and your CNC crashing.

ESS by being a dedicated controller removes this burden from the computer and leaves you free to run other programs even while your CNC is running.

Without a dedicated controller like ESS, Mach3/Mach4 can run only on a 32-bit computer. With ESS, Mach3/Mach4 works on 64-bit computers.

Considering most computers available today are 64-bit, you will most likely need ESS to run Mach3/Mach4 from your computer.

This controller is highly popular among Mach3/4 users for all kinds of CNC applications including CNC routers, plasma cutters, laser cutters, and waterjet cutters.

You can support up to 6-axis motion with this controller which is a real benefit if you are looking for that.

For connecting to stepper drivers, you can either connect directly from the ethernet SmoothStepper or use a breakout board.

Using a breakout board is really useful as it offers multiple pinouts lending you significant flexibility in connecting other accessories to your CNC setups, such as vacuum pumps, coolant pumps, encoders, and optoisolators.

One of the best breakout boards for use with the ethernet SmoothStepper is the C25XP – Smooth Stepper Integrated Board from CNC4PC, a Florida-based manufacturer.

C25XP breakout board can be bought either as a separate breakout board or with ESS integrated into it.

C25XP - Breakout Board
C25XP – Breakout Board

To use this controller, you need a PC running Windows OS. However, that’s a limitation of Mach3/4 rather than the controller itself.

ESS can run almost any stepper driver. A highly popular and successful combination is ESS (controller) + C25XP (Breakout Board) + Gecko 540 (Multi-axis stepper driver).

Warp9 Tech Design also offers a USB version of the SmoothStepper called USB SmoothStepper (USS).

However, it does not offer the isolation from the rest of the circuit that the Ethernet SmoothStepper offers.

The overall cost of a Mach3 control system

Controller $214
Software -Mach3$175
Breakout board-C25XP$125
Total Cost$514

Cost analysis of running a CNC with Mach3 control system

At $480, this control system can be used to power almost any non-industrial CNC application.

CNC brands targeted at Small businesses, such as the highly-rated Avid CNC (formerly CNC router parts) use Ethernet SmoothStepper (ESS) for running Mach4 on their PRO machines.

Overall, the Ethernet SmoothStepper is one of the most popular, tried, and tested solutions for running Mach3/Mach4 and it’s difficult to go wrong with one.

Ethernet SmoothStepper
  • Simulates three standard parallel port interfaces.
  • Operate a CNC machine from an Ethernet connection.

5. Buildbotics CNC Controller – Best Raspberry Pi CNC Controller

Buildbotics CNC Controller
Buildbotics CNC Controller
FeaturesBuildbotics CNC controller
Number of Axes4
Axis slave?Yes
Stepper drivers included?Yes
Microcontroller8-bit ATxmega192a3u
Supported firmwareBuildbotics CNC controller firmware

Buildbotics CNC controller

The Buildbotics CNC machine controller is an advanced open-source CNC controller that’s used in CNCs such as the Onefinity CNC Router.

The controller has a Raspberry Pi 3 connected to an ATxmega192a3u microcontroller.

Raspberry Pi inside

The Buildbotics CNC controller is the best Raspberry Pi-based CNC controller on the market today.

In this controller, the G-code generated in the computer is sent to Raspberry Pi which sends it to the microcontroller for processing and passing signals to the stepper drivers and other components.

The controller ships in a neatly enclosed case as a plug-and-play device.

Although the microcontroller is an 8-bit one, the Raspberry Pi 3 in the controller gives it WiFi and Ethernet connectivity to communicate with the computer.

The Buildbotics is a 4-axis CNC controller and both the hardware and software are open-source.

The decision to make the controller open-source will help ensure that the development of this controller doesn’t stagnate like many other proprietary controllers.

You don’t need a dedicated computer to run this controller.

The controller functions as a standalone device, which is not surprising considering a full computer is already inside the controller (Raspberry Pi 3).

To access this controller, a web interface is provided. You can access this web interface through a web browser on any device through WiFi or Ethernet.

Buildbotics Control Software
Buildbotics Control Software

You can also connect a monitor, keyboard, and mouse to this controller and operate it. This is because the CPU is already inside the controller.

This controller is available as a kit and it sells for around $499 plus shipping.

What you get for that price are the plug-and-play controller, a Logitech gamepad, DB25 breakout board, and a 36V Meanwell power supply bundle.

Although the price may appear high compared to other controllers on this list, you need to factor in the value of everything you are getting in the kit.

The stepper drivers are included with this controller.

When comparing with other controllers that don’t have integrated stepper drivers, factor in the cost of buying external drivers.

The four stepper drivers are integrated into the controller and they are quite powerful. The internal stepper drivers can supply up to 6A of current.

That’s enough to run almost any hobby CNC application and can be used to run some NEMA 34 motors as well.

Also, the power bundle is included in the price. For most controllers on the market, you need to buy the power bundle extra.

The wired USB gamepad is a quirky accessory using which you can jog the machine easily in an intuitive manner.

Buildbotics also offers a wireless gamepad to buy, if you don’t prefer a wired gamepad.

Buildbotics controller back side
Buildbotics controller backside

For spindle control, the Buildbotics controller has two choices, PWM and RS485.

The PWM port is for connecting low-power spindles such as the ones on engravers.

The RS486 port is for connecting to VFDs that control more powerful air/water-cooled spindles.

Buildbotics controller has been successfully tested on a variety of CNC applications such as Taig Benchtop CNC mill, an OX CNC router, a K40 LASER upgrade, and a Dyna Myte 2400 retrofit.

Clearly, this controller can work in any CNC setting, and not just a CNC mill.

Support and Documentation

Although Buildbotics controller is still growing in popularity, it has a company-managed forum through which you can get your queries addressed.

One very important advantage to buying this controller is that they offer US-based phone support for any query to their customers.

The company Buildbotics LLC is based in Petaluma, CA, and was founded in 2014.

The popular open-source CAM software CAMotics was created by one of the founders of Buildbotics.

Buildbotics does not offer a formal warranty for this controller, although they are known to support their customers well if there are issues.

Overall thoughts

Overall, Buildbotics controller is an impressive hardware and software solution that truly belongs to the 2020s.

With versatile features like WiFi, gamepad, and standalone nature, it does make the other popular controllers look outdated.

It also complements those nifty features with powerful integrated stepper drivers and a capable control system that can run even NEMA 34 stepper motors.

All of these make the Buildbotics controller a good option for building your CNC application.

I go into much more detail about Buildbotics here- Buildbotics CNC Controller Full Review [2023]

6. Mesa 7I76E CNC Controller – Best LinuxCNC Controller

Mesa 7I76E board
Mesa 7I76E board
FeaturesMesa 7I76E CNC controller
Number of Axes5
Axis slave?Yes
Stepper drivers included?No
MicrocontrollerIt uses the processing power of the computer
Supported firmwareMesaFlash

Mesa 7I76E CNC controller card
Linuxcnc logo

The mesa 7I76E is the best and most popular controller board (FPGA) for LinuxCNC.

The 7I76E is complete in itself and combines an FPGA (controller) card with a breakout board.

Like Mach3 and Mach4, LinuxCNC turns your PC itself into the controller and you don’t need a microcontroller chip like in GRBL-based CNCs.

Therefore it is not strictly necessary to have a controller card like Mesa 7I76E to run a CNC with LinuxCNC.

However, it is beneficial to have a separate ethernet controller card like Mesa 7I76E instead of just using your PC as the controller for several reasons:

  • An ethernet-based card like Mesa 7I76E eliminates the need for having a computer with a parallel port and you can run it off even a laptop.
  • It transfers the bulk of the heavy lifting off your computer to the card like the hardware step generation and encoding.
  • If you run high-current stepper motors and drivers, using a card will result in a smoother step output.
  • The card allows connecting encoders like a spindle encoder, which can give you feedback and alert you in case of issues.
  • Gives you significantly more i/o pins compared to the parallel port.
  • Isolates your computer from the circuit of the CNC.

Mesa 7i76e is connected to the computer through an ethernet cable.

On the CNC end, you connect your stepper drivers and spindle motor to the Mesa 7I76E.

This CNC controller is capable of supporting up to 5-axis motion.

Mesa 7I76E in a CNC
Mesa 7I76E in a CNC

The Mesa 7I76E can be bought from the online store of mesa electronics for around $220.

There is a setup involved in configuring the Mesa 7I76E.

Although LinuxCNC is considered to have a high learning curve among CNC Control Software programs, the documentation is excellent enough to guide you all the way through.

For running LinuxCNC, you need Linux OS on your computer and most people create a dual-boot system on their computer so that it can load either Windows or Linux.

LinuxCNC is an open-source CNC control system known to have vast capabilities but with a high learning curve.

Overall Thoughts

The Mesa 7I76E is undoubtedly the best motion controller card for LinuxCNC and if you can learn your way around LinuxCNC, you can do quite a lot with it.

7. UC100 USB CNC Motion Controller – Best UCCNC Controller

UC100 motion controller
FeaturesUCCNC Motion Controller
Number of Axes6
Axis slave?Yes
Stepper drivers included?No
MicrocontrollerIt uses the processing power of the computer
Supported firmwareUC100 firmware verision 01.01

UCCNC Motion Controller

UCCNC is a CNC control system made by the brand CNC drive.

They make motion controllers which are compatible with Mach3/Mach3 and also their own control software UCCNC.

The most affordable and popular among those motion controllers is the UC100 USB motion controller.

The UC100 controller is a USB motion controller for CNC machines, manufactured and sold by the brand CNC drive (based in Hungary).

UC100 works with UCCNC control software and this hardware and software combination is a popular choice.

This controller is also a popular choice for Mach3/Mach 4-based systems and is an alternative to Ethernet Smoothstepper.

It connects to the computer through a USB port.

With a deceptively simple look, it is easy to think of UC100 as a simple Parallel Port to USB converter.

However, housed in that simple device is a full-fledged motion controller that is capable of running most hobby CNC mills out there.

The UC100 can support up to 6-axis motion, which is a great advantage.

It costs around 80 euros (~$100) plus shipping from the CNC drive webshop.

UCCNC is not recommended for use on CNC lathes due to the lack of several key functions.

UC100 USB Connection to PC
UC100 USB Connection to PC

UC100 vs UC300ETH vs UC400ETH

CNC drive also offers two other motion controllers that are more expensive compared to the UC100. Those are UC300ETH and UC400 ETH.

Price€80 (~100 dollars)€125 (~150 dollars)€110 (~130 dollars)
I/O portsDB25 port 5 IDC26 ports2 IDC26 ports
Max. Kernel (Hz.)100 kHz400 kHz400 kHz

Comparison of UCCNC-based Motion Controllers

The first and biggest advantage to getting the UC300ETH/UC400ETH is the more number of ports they offer.

If you want to connect multiple breakout boards this is a necessity.

The second important advantage is that they use an ethernet connection and that means your computer is isolated from the rest of the circuit.

With the UC100, you need to use an optically isolated breakout board to prevent potential damage to your computer.

Lastly, the maximum kernel frequency is higher for UC300 and UC400.

Now, the exact maximum kernel frequency you need can only be calculated by knowing the answer to some questions.

Such as the maximum feed rate you need, the maximum step rate of your stepper driver, and whether you need encoders in each axis or not.

As a thumb rule, the kernel frequency in UC100 is sufficient for most hobbyist applications.

The only situation where I think the kernel frequency of UC100 would be a limitation for you is if you are planning to use a servo drive for your CNC.

Breakout board for UC100

You will most likely need a breakout board for making the connections from the UC100 to your other electronic components.

Make sure to use an optically isolated breakout board with the UC100.

The best option is to get the breakout board as well from the CNC drive.

I recommend the UCSB single port breakout board (BoB) with the UC100.

UCSB BoB has an optically isolated IDC26 port with a standard LPT port pinout. It can support 12 outputs and 5 inputs.

UCSB Breakout Board
UCSB Breakout Board

UCCNC Software

The control software that’s commonly used with the UC100 is the UCCNC software by CNC drive.

It is a fully capable control software trusted by hobbyists for quite some time.

The software is paid and each software license is tied to a single motion controller (like UC100 or UC300ETH).

This means, if you wish to operate say two CNC machines with two UC100 controllers, you need to buy two software licenses.

Although this is a disadvantage, the lower cost of UCCNC compensates for this.

A single license of UCCNC costs around €55 (~65 dollars).

CNC drive often runs promotional offers on its webshop for UC100 (hardware) and UCCNC(software) bundles and that can bring down the costs further.

UC100 In/Out Monitor
UC100 In/Out Monitor

Overall cost of a UCCNC control system

Controller -UC100€80 (~$100)
Software -UCCNC€55 (~$65)
Breakout board-UCCSB€45 (~$53)
Total Cost€185 (~$218)

Cost analysis of running a CNC with a UCCNC control system

At $218, the cost to set up a CNC machine with a UCCNC control system is less than half that of a Mach3/Mach4-based control system.

Support and Community

CNC drive hosts an online community on their website. The community is quite active and any query you have is likely to be answered quickly.

Other than that you have the option of emailing CNC drive for support. Phone support is not offered.

Since CNC drive is based in Hungary, it operates through distributors such as CNC4PC in the USA as well.

Overall thoughts

UC100 controller is a highly affordable and robust solution for any hobbyist looking to control their CNC machine.

With thousands of satisfied users and years of experience behind their products, it’s difficult to go wrong with a UCCNC-based control system.

UC100 USB CNC Motion Controller
  • Replaces the outdated LPT port.
  • Controls up to 6-axis simultaneously.

8. Mk3/4 USB CNC Controller – Best CNC Controller for Plasma

CNC USB controller Mk3_4 (4 axis)
CNC USB controller Mk3_4 (4 axis)
FeaturesMk3/4 USB CNC Controller
Number of Axes4
Axis slave?Yes
Stepper drivers included?No
MicrocontrollerIt uses the processing power of the computer
Supported firmwarePlanetCNC Mk3 series controller

Mk3/4 USB CNC Controller

PlanetCNC is a combined hardware and software solution for many types of CNC applications like CNC mills, lathes, plasma cutters, laser cutting, and foam cutting.

They make two controller boards, Mk3/4 (4-axis) and Mk3 (9-axis).

As a CNC plasma controller, the Mk3/4 is preferred over GRBL, Mach, and LinuxCNC by many people.

The company PlanetCNC, d.o.o. is based in Slovenia, EU.

The hardware part of PlanetCNC, the motion controller is offered in two models-Mk3/4 (4-axis) and Mk3 (9-axis).

The Mk3/4 4-axis CNC controller is the more popular one as most hobbyist applications need only up to 4-axis support.

The cost of the controller is around €146 (~$160).

Mk3/4 controller connects to the computer through a USB connection.

With 3 digital inputs and 4 digital outputs onboard, the Mk3/4 is a breakout board and controller rolled into one.

Mk3_4 USB Controller IOs
Mk3_4 USB Controller IOs

This controller can deliver up to 110 kHz step frequency, which is excellent for most hobbyist applications.

It works with almost all stepper drivers on the market.

If you wish to connect a stepper driver that connects with a DB25 cable, like the Gecko stepper driver, you need to get the DB25 adapter sold by PlanetCNC.

You also need to get an 8 – 24V DC power supply for powering this controller.


The control software offered by PlanetCNC is called PlanetCNC TNG software.

The software is free but it works only with controller boards sold by PlanetCNC.

So, effectively, you get the control software for free when you buy the Mk3/4 USB controller.

PlanetCNC recommends some best practices while using their control software.

You should ideally have a computer dedicated to running PlanetCNC and should not use it for other purposes.

Other software programs can interfere with the functioning of TNG software and that can result in catastrophic results.

TNG software is quite easy to use for even beginners and it has several built-in features that make things easy for CNC work.

However, it also supports advanced functionalities if that’s what you need.

Since the software is not open-source, the development work is not as fast-paced as GRBL or LinuxCNC.

Overall cost

Controller -Mk3/4$160
Software -TNG0
Total Cost$160

Cost analysis of running a CNC with PlanetCNC control system
Mk3_4 controller used in a CNC setup
Mk3_4 controller used in a CNC setup

Support and Documentation

PlanetCNC does not have a forum of its own but most of the online community discussions about PlanetCNC happen on the CNCZone forum where representatives of the company are also involved.

There is no formal warranty offered on this controller.

However you can return the product within 14 days if you wish, but you need to pay the shipping fee to get it back to the manufacturer.


PlanetCNC control system is quite popular among the hobby CNC crowd who love it for its ease of use and value for money.

9. Acorn CNC Controller

Acorn CNC Motion Controller
Acorn CNC Motion Controller
FeaturesAcorn CNC Motion Controller
Number of Axes6
Axis Slave?Yes
Stepper drivers included?No
PriceCheck Price

Acorn CNC Motion Controller

Acorn CNC controller by Centroid CNC is an end-to-end hardware plus software solution for CNC applications like Milling Machines, Lathes, Routers, and other special applications.

This controller is highly popular in retrofitted CNC systems.

Centroid CNC offers CNC retrofitting as a turn-key service where they upgrade old CNC machines using their control system for a fee.

Acorn CNC controller is a motion controller and breakout board rolled into one. So you don’t need a separate breakout board for using the Acorn controller.

The kit contains the Acorn control board, plug-and-play relay module, power supply, and a 15′ ethernet cable.

Acorn CNC Controller Kit
Acorn CNC Controller Kit

At the core of the Acorn controller is the Beaglebone green motion control CPU.

Beaglebone green is an open-source single-board computer like the Raspberry Pi.

The processor that powers the Beaglebone green is the AM335x processor from texas instruments.

Much like the Mach3 motion controllers, the Acorn controller takes away the critical processes from the computer to the controller.

This avoids the need for having a powerful computer to run the CNC and the controller takes much of the load.

This controller is capable of supporting up to 4-axis motion.

If you need a controller that can support more than 4-axis motion, centroid CNC offers controllers that support 6-axis (Allin1DC CNC controller) and 8-axis (Oak CNC controller)  motion.

However, they cost significantly more compared to the Acorn controller.

The possible pinouts in the controller are extensive.

As a breakout board, it can directly connect to stepper motors, stepper drivers, a touch probe, limit switches, an encoder, and spindle drive control.

If you wish to connect a stepper driver like Gecko, the Acorn controller has a legacy DB25 port for connection.

In terms of spindle support, Acorn CNC can run VFDs that support 0-10 VDC input.

Similar to the Ethernet Smoothstepper, Acorn CNC also connects to the computer through an ethernet cable.

This isolates the computer from the shocks in the circuit.

The control software solution in the Centroid CNC control system is the Centroid CNC12 software.

CNC12 is a software program that has industrial-grade capabilities and this makes it highly suitable for industrial CNC retrofits, unlike Mach and GRBL.

Centroid CNC recommends using a touch-enabled computer as CNC12 comes pre-configured for use with a touch-based system.

To fully utilize the benefits of the interface system offered by CNC12, it’s highly recommended to get a computer that accepts touch input.

CNC12 has a free version that users of Acorn CNC controllers can utilize.

However, the free version limits the size of the G-code file to 50Kb for CNC mills.

The free version is recommended for hobbyists and startup shops.

Before you decide on the Acorn controller, you need to check the maximum size of the G-code files you plan to generate.

50 kb is a reasonably high file size for most hobbyist applications.

If your file size is going to exceed that, you should factor in the price of the PRO version of CNC12 software into your overall budget.

If your requirement is more than that in your CNC mill, Centroid CNC offers the MillPro version of the CNC12 software which costs $549 for a single license.

Centroid CNC runs a dedicated online community for its customers at the CENTROID forum, which is highly active and useful for free support.

In addition, Centroid CNC offers US-based phone support to its customers for a fixed fee.

One big advantage to buying the acorn CNC controller is the amount of support you get compared to other controllers in this list.

Overall Thoughts

With the Acorn CNC controller, you get an industrial-grade motion controller for a very affordable price.

Also, you get the support of a big brand that comes with perks like phone support, warranty, and a company-maintained online forum.

The drawback of the Acorn controller is that the software upgrades(PRO version) cost a bit.

Overall, the Acorn CNC controller from centroid CNC is a good all-in-one option for running your CNC mill, lathe, or router.

10. Masso G3 CNC Controller

Masso G3 Standalone CNC Controller
Masso G3 Standalone CNC Controller
FeaturesMasso G3 CNC controller
Number of Axes3/4/5
Axis Slave?Yes
Stepper drivers included?No
MicrocontrollerRasperi Pi-based
FirmwareMasso G3 v5.03

Masso G3 CNC controller

Masso G3 is a standalone CNC controller from Masso CNC, an Australia-based brand quickly becoming popular worldwide.

The G3 controller does not require a PC to operate it and it is one of the biggest advantages of this controller.

Masso offers its control system in 3-axis, 4-axis, and 5-axis versions, and you can make your choice from these.

There is no hardware difference whatsoever between these versions and the same G3 controller is used for all three versions.

The difference is only in the control software.

If you buy the 3-axis (XYZ) version of the Masso g3, you can upgrade to a 4-axis (XYZA) or 5-axis version (XYZAB) later by paying an extra fee.

The upgrade happens as a software update.

For people running a CNC mill with dual drive motors, with the 3-axis Masso, you can only manually square the machine when you do a homing routine.

Dual drive motors refer to having a stepper motor for each side of the Y-axis and it’s really common in CNC mills that are not very small.

You need to use something like a physical end-stop to do the squaring with the 3-axis Masso G3.

With the 5-axis Masso, you get auto-squaring when you do a homing routine and that makes this really easy.

This is because the Y-axis can only be slaved by the software with the B axis, and you get the B axis only in the 5-axis version.

Since the 5-axis version is only $60 more compared to the 3-axis version, I highly recommend you get the 5-axis Masso G3.

Similarly, Masso G3 has control software for three types of CNC machines, CNC mills, CNC lathes, and CNC plasma cutters.

The hardware is the same (Masso G3) for all three types of CNCs, but the software is different.

All three software programs are provided for free when you buy the Masso G3 controller.

The Masso CNC lathe control system is becoming quite popular among users who find Mach3 and UCCNC limiting for a CNC lathe application.

Note that the lathe control system of Masso is a 2-axis system.

Masso G3 can produce up to 110 kHz pulse rates on each axis.

Pulse rate has an indirect relationship with the feed rate that you can run on your CNC.

Although there are a few CNC controllers which can do higher frequencies, for most hobbyists, 110 kHz is high enough for any CNC machine application.

Masso G3 board has quite extensive I/O options with 24 optically isolated inputs and 18 outputs.

Masso G3 Features and Pinouts
Masso G3 Features and Pinouts

Two types of spindle controls are available on the board, PWM control for engravers and 0-10 V signal for VFD spindle control.

Masso has detailed documentation on their website for wiring instructions for all popular VFD spindles.

For offline control and jogging, Masso offers a handheld MPG (Manual Pulse Generator) pendant.

Masso MPG Pendant
Masso MPG Pendant

The MPG pendant works like a handwheel using which you can move the CNC in any of the five axes, control feed override, and spindle override.

In terms of connectivity, Masso G3 can accept G-code through WiFi from any device (computer, phone) through their MASSO Link software.

If you don’t want to use WiFi you can also connect to Masso through a USB connection from your computer.

Once the G-code is transferred to the Masso controller, you don’t need the computer to be connected.

If you are connected to the Masso controller via WiFi you can monitor the status of your machining job from anywhere.

Note that what you get with the Masso G3 controller, is just the controller board, and things like stepper drivers, power supply units, and stepper motors should be bought separately.

You need a power supply that can deliver 12 and 24 VDC voltage with a minimum 1.5A output.

Masso G3 also has a touch version which costs around $400 more.

It gives you industrial-style touch control at an affordable price.

Masso G3 Touch Version
Masso G3 Touch Version

If you think that costs too much, you can use a touch screen monitor that’s compatible with Masso, instead of the Masso touch controller.

Note that you need to buy the Masso touchscreen upgrade for the control software to work with the touchscreen monitor.

Another feature that makes the Masso industrial grade is its built-in support for Automatic Tool Changer (ATC) Spindles.

Masso G3 supports several types of automatic tool changer spindles for both CNC mills and CNC lathes.

If you have a tool changer system, you can check the Masso documentation to check for compatibility.

If you are planning to buy a used Masso, you can transfer the license from the original owner to you by emailing Masso support.

This is something that will improve the resale value of a Masso controller if you ever decide to sell it.

After its launch in 2019, Masso G3 had some teething issues like software bugs and compatibility issues.

However, the Masso brand has solved most of those initial hiccups and several CNC brands have now adopted Masso for their CNC machines.

Major brands include the highly popular Sherline Mills and Lathes, 3Dtek Routers (popular in Australia and UK), CANCAM routers (popular in Canada), and Revo CNC (Turkey).

Support and Documentation

Masso has excellent documentation that details everything you might need to operate the Masso G3 controller.

In addition, their dedicated online forum is quite active and useful.

For formal support, Masso has an email-support option and a support portal where you can raise tickets in case of issues.

Masso does not offer phone support, presumably because they’re based in Australia.

All the products made by Masso have a 12-month formal warranty on them in case of manufacturing issues.

Overall Thoughts

Masso G3 is a good controller that’s fast-growing in popularity.

Although not as popular as some of its competitors, it offers near industrial-grade control and quality in its standalone controller.

Although it can seem pricey at first, once you factor in the ease of use, free software, good I/O options, and the ability to operate without a PC, the value becomes apparent.

CNC Controllers that didn’t make the cut

Several other controllers were also considered but they were not chosen in this list due to multiple reasons.

  • TinyG – Development has stopped for all practical purposes.
  • RepRap (Duet 3) – Due to its primary focus on 3D printing rather than CNC.
  • GRBL-based Chinese controllers – Due to lack of after-sale support.

John Abraham
Hey I'm John. I write about Manufacturing, Metalworking, CNCs and Lasers at Mellowpine. If you have any questions related to CNCs or Lasers, I'd be happy to answer them. Reach me at mail@mellowpine.com