At the core of every 3D printer (or CNC machine in general), is the controller board.
This is the brain of the system that controls all aspects of the printer, from the inputs such as thermistors, to the outputs (such as motors or heaters).
Additionally, many controllers are responsible for processing the G-code and telling the toolhead where to go.
The firmware is the software that defines how the controller hardware should behave, and provides a software interface for modifying the system.
Depending on the requirements, this could be Marlin, RepRap, Klipper, or some other type of firmware.
Your selection of controller will depend on your own specific requirements, such as number of motors, or fans, clock frequency, and of course, cost.
In this article, we will take a look at a variety of 3D printer controllers for a range of needs and budgets.
How to Choose the Right 3D Printer Controller
There are a few factors that you should consider before rushing out and buying a new controller.
Are you building a printer from scratch, or are you simply modifying a printer that you purchased?
Maybe you fried your old controller somehow, or you blew the stepper drivers and just need a drop-in replacement.
Or maybe, you are building one that needs half a dozen motors for dual extrusion and various other motor axis and need something a little bigger.
Whatever the situation, make sure that you get the right controller for your needs.
There is no point in spending $600 on a high-end controller with ten motor drivers when your $200 printer couldn’t possibly accommodate so many motors physically.
And conversely, if you want to build a super-reliable large format pellet extruding printer with multi-zone bed heating, you might want something a little bit more configurable than something that was designed to drop into an Ender 3 as a replacement.
Much of the configuration goes on when configuring and compiling the firmware, but not every single board works with every type of firmware.
If you have no firmware preference, then no problem.
But if, for example, you were used to working with Marlin, and you don’t fancy learning a new firmware, then you should seek out a controller that will run the firmware that you are used to.
Number of Motors
3D printers are basically structures, with a whole bunch of motors and other ancillary components bolted to them.
The motors drive all the motion in the system, including extrusion and the motion on each axis.
Some printers have two motors for each axis, which can improve stability and speed.
If the number of motors is an important factor in your printer design, then you should seek a controller with enough motor drivers to do the job that you need.
When making your own printer from scratch, personally, we think more is better. It gives you the option to upgrade later if you choose to add more extruders and whatnot.
Most basic controllers have 2 ports for heaters. They have one for the hotend and one for the heater bed.
And they often have a corresponding amount for the thermal sensor (thermistor or thermocouple).
Heater beds are expensive, especially when you want to go bigger.
If you want a bigger heated bed, then it may be cheaper to buy multiple smaller ones and control them separately, rather than splashing out on a singular large heater bed and running it off one heater output from your board.
If you want more heated bed zones, or if you wish to run multiple hotends on the same printer, you will need more than just 2 heater outputs and thermal sensor inputs.
The clock frequency of the controller determines how quickly it can process these instructions and send signals to the stepper motors that control the movement of the print head.
A higher clock frequency allows the controller to process more instructions in a given amount of time, which can result in faster and more accurate movement of the print head.
This is particularly important for printing intricate and complex models with a high level of detail, where any delays or inaccuracies in the movement of the print head can result in poor print quality.
However, there is a tradeoff between clock frequency and cost, as higher frequency controllers can be more expensive.
Therefore, the optimal clock frequency for a 3D printer controller depends on the specific needs of the user, the complexity of the models being printed, and the budget available for the printer’s components.
8-bit or 32-bit? How about a 64-bit controller?
The bit number of a processor or controller is important because it determines the maximum amount of information that can be processed and stored at once.
The bit number refers to the size of the data bus or the number of bits that can be processed by the processor or controller in a single clock cycle.
For example, an 8-bit processor can handle data in 8-bit chunks, while a 32-bit processor can handle data in 32-bit chunks.
This means that a 32-bit processor can process and manipulate larger and more complex data sets than an 8-bit processor.
In the context of a 3D printer controller, the bit number can impact the speed and accuracy of the printer’s movements and the complexity of the models that can be printed.
A higher bit number can allow for more precise and efficient control of the printer’s components, resulting in higher quality prints and faster printing times.
Just like the clock frequency, bigger is better, and there is no need to be purchasing an 8-bit controller in 2023, when you can get a 32-bit controller for a few bucks.
There are even 64-bit controllers out now, but that will be surplus to requirements for most users.
You can get a very cheap Arduino-type RAMPS controller for very little money.
And you can get 32-bit boards with multiple-motor drivers for not much more (think $30 to $40). But you get what you pay for, ultimately, and spending a few extra bucks on a high-end controller can have benefits, especially where reliability is concerned.
But in most cases, and especially for replacing existing boards in low-cost systems, don’t expect to pay more than $100.
It’s only when you start needed significant extra features do you need to start spending too much more.
5 Best 3D Printer Controllers
So, you’ve made your decision on what you want from your 3D printer, and what your budget is.
Let’s take a look at what your options are.
The following 3D printer controllers are widely available online from sources such as Amazon, and from the manufacturer’s own websites in many cases.
Duet 2 WiFi
The Duet 2 from Duet3D is a higher end controller suitable for a wide range of machine applications such as CNC routers, laser cutters, and more.
It is used in several industrial-grade 3D printers, such as those from Modix3D and Tractus3D.
There are two versions available, the standard Duet 2, and the Duet 2 Wifi.
The latter comes with onboard Wi-Fi with its own Wi-Fi antenna. No need for additional purchases for Wi-Fi modules here.
It also comes with 3 controllable fan outputs, 2 always on fan outputs, 3 thermistor inputs, and 3 heating outputs for all your thermal-related needs.
The Duet 2 runs exclusively on RepRap firmware, so be aware of that before you invest in this board.
- Clock speed: 120MHz
- Microcontroller: ATSAM4E8E / 120MHz ARM Cortex M4F
- Networking/Comms: WiFi, WPA-2 encryption; USB; serial port, Ethernet
- On-board Stepper drivers: 5 x TMC2660
- Supply voltage: 11-25V DC
- Price: $170
Pros and Cons
- It has Wi-Fi and is reliable
- Forum support is a little lame, and it’s pricey
SmoothieBoard is a powerful and flexible open source hardware 32-bit CNC controller board designed to control various small-sized CNC machines such as 3D printers, laser cutters, CNC mills, pick and place machines, and more.
The board is built around the LPC1769 or LPC1768 Cortex-M3 chip, which provides high-performance processing power and is highly customizable.
One of the main advantages of SmoothieBoard is its modular firmware (named “Smoothieware”), also open-source and licensed under GPL, which allows users to customize and add features to the board according to their specific needs.
The firmware is designed to support a wide range of input and output options, such as temperature sensors, endstops, and more, and can handle various stepper motors, servos, and other CNC machine components.
SmoothieBoard can also be scaled to control larger machines by using external drivers.
It has a user-friendly interface and can be easily configured through a web-based user interface or via USB, allowing users to make adjustments and monitor their CNC machines in real-time.
- Clock speed: 120MHz
- Microcontroller: LPC1769 LPCXpresso
- Networking/Comms: WiFi, USB, serial port, Ethernet
- On-board Stepper drivers: 3 to 5 Allegro A4982 stepper drivers
- Supply voltage: 12-24V DC
- Price: $199
Pros and Cons
- Open source, so good community support.
The BIGTREETECH Octopus Pro is a 32-bit controller with (wait for it)…8 onboard motor drivers, which is probably why it is called the “Octopus”.
It comes with Raspberry Pi interface, 6 x controllable PWM fans, 2 x normal fans, 4 x heating cartridge connections and has a core frequency of 180 MHz, providing enough power to realize even the most demanding applications.
It’s also pocket-friendly, and provides a lot of bang for your buck.
It’s ideal for a replacement controller on IDEX-type systems due to its multiple motors, or for building your own from scratch.
- Clock speed: 180 MHz
- Microcontroller: 180Mhz ARM Cortex-M4 CPU
- Networking/Comms: USB-C, CANbus, optional Wi-Fi
- On-board Stepper drivers: 8x TMC5160
- Supply voltage: 12 to 24V DC
- Price: $69.99
Pros and Cons
- Lots of motors, great price
- Documentation is not great
Makerbase MKS Eagle
The Makerbase MKS Eagle is a 3D printer control board designed to provide high-performance control of 3D printers.
It is based on the 32-bit STM32F407VGT6 MCU and features six motor driver slots, which can control up to six stepper motors.
The board also includes a large number of connectors and ports, including multiple USB ports, an Ethernet port, a micro SD card slot, and a TFT touch screen display port.
Additionally, it features a variety of sensors, such as temperature sensors and end-stop sensors, to ensure accurate and safe printing.
The MKS Eagle supports a range of firmware options, including Marlin and Repetier, and is compatible with a variety of 3D printer software, including Cura and Simplify3D.
The board is also designed to be easy to install and use, with plug-and-play functionality and clear, simple wiring diagrams.
- Number of supportable extruders: 2
- Clock speed: 168 MHz
- Microcontroller: STM32F407VET6
- Networking/Comms: Ethernet, WiFi, USB
- On-board Stepper drivers: 6x TMC 2209 drivers for each motor output
- Supply voltage: 12 to 24V DC
- Price: $84.99
Pros and Cons
- 6 motor outputs and not locked to a single firmware, price
- Lackluster support, Marlin builds can be buggy
SKR mini E3 V3.0
The BIGTREETECH SKR MINI E3 V3.0 32-bit Control Board is a budget-friendly option designed as a silent replacement for the Ender 3 (and other Creality printers).
It will also work on plenty of other machines, but dimensionally speaking, it fits well in the Ender 3.
If you have an Ender 3 with the older (noisier) stepper drivers, or if you simply fried your old board, this will be your go-to solution in most cases.
- Clock speed: Microcontroller: ARM Corex M0 + STM32G0B1RET6
- Processor: Networking/Comms: PC interface via USB C with 115200 baud
- On-board Stepper drivers: TMC2209 drivers with dual Z-output
- Supply voltage: 12V to 24V DC
- Price: $41.99
Pros and Cons
- Low price 32-bit board
- Easy replacement/upgrade for Ender 3
- Runs multiple firmware
- Documentation could be better
Our overall verdict is that if you are looking for a simple replacement for your defunct controller board, shop around, find one that physically fits your printer, and buy it.
And while you’re at it, see if you can sneak in a couple of upgrades to your current defunct board.
The SKR mini E3 V3.0 is not only a replacement for the Ender 3 mainboard, but is a defacto upgrade, for example, as it has silent drivers as standard.
In fact, we have looked at two BIGTREETECH boards here, but the Chinese company has many more to offer, so take a look at their boards if you have another printer that isn’t the Ender 3.
You will find that they will likely have a solution that will replace or upgrade your setup.
And if you are building a printer from scratch, then we would recommend getting a board that has as many motor drivers and heater outputs as possible, especially if you are building a large printer.
The Octopus Pro is a good low-cost solution, or if you want a higher end board with CNC-like reliability, then we would recommend the Duet 2.
But before buying the Duet 2, be sure that it’s really what you need.
They are not cheap boards, and if you simply want a board with many motors, then there are other boards available and at lower cost.