Mach3 Setup

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Mach3 is the most popular CNC control software available for hobby and professional CNC machines. It is capable of running many different kinds of CNC machinery, and is extremely stable.

You can download a trial copy of Mach3 at http://www.MachSupport.com/.

Fully licensed copies are available from A Quick CNC in the store.

Mach3 Setup XML Files

For simple and straight setup, you can download these XML configuration files. They will be able to run your machine with some very simple tweaking. Please check these files regularly, as it is possible they will be updated in the future.


Current Configuration Files


CNC Controller

For our Unipolar CNC Controller (version 1.0.3+)

Last Updated December 25, 2012


Legacy Configuration Files


Kickstarter CNC

For our Kickstarter machines with the included electronics only.

Last Updated October 30, 2011


Setting up Mach3

Ports and Pins

Mach3 Ports and Pins Configuration
Opening the main connection configuration for the input and output using "Config > Ports and Pins" allows you to setup your controller to communicate with Mach3.

On the main "Port Setup and Axis Selection" screen, you will want to select a Kernel Speed of 35000 Hz. If your computer is faster, you may be able to set this higher. Use the Driver Test program (see "Testing Computer Speed" section) to test how your computer performs when you increase the Kernel speed.

Motor Outputs

Mach3 Motor Outputs Configuration

On the "Motor Outputs" screen you can enable and disable the axes. Place a checkmark in the X, Y, & Z "Enable" boxes, and apply the following pins:

  • X-Step: 3
  • Y-Step: 5
  • Z-Step: 7
  • X-Direction: 2
  • Y-Direction: 4
  • Z-Direction: 6

Set the "Step" and "Dir" port as 1. If you want to reverse the directions of any of the axes, place a checkbox in the "Dir Low Active".

Input Signals

Mach3 Input Signals Configuration

On the "Input Signal" screen, you will want to scroll down and enable the EStop button. You will need to do this, the machine will not run without the EStop setup. Place a check mark in the Enabled box, assign the Port as #1, Pin as #13. If you do not have an EStop switch, you will need to place a check mark in the "Active Low" box. (This will simulate that the EStop button is always released.)

Output Signals

Mach3 Output Signals Configuration

On the "Output Signals" screen. Place a check mark in the "Enabled" for the Digital Trigger. This will enable your control board when your Mach3 is running. Set the Port as #1 and Pin as #1.

Setting Motor Velocity & Acceleration

The motor configuration can be set by going to Config > Motor Tuning and Setup on the Mach3 main screen.

There are three main settings you need to set for each motor. "Steps per", "Velocity" and "Acceleration".

"Steps per" is the number of steps per inch, which is the number of steps the motor needs to turn in order to move the CNC one inch. It is based almost entirely on the type of leadscrews used in the machine. A formula for determining the setting can be found on the Stepper Motor Calculations page. For most of our machines, the setting is 4800 for the X & Y axis, and 9600 for the Z axis.

"Velocity" is the speed that the CNC can travel, in inches per minute. Depending on the settings of the CNC controller, power and stepper motor size, this number can range from 1 IPM to 600 IPM. For our machines 20 IPM is a good base to test movement, with higher speeds being capable through Stepper Motor Tuning.

"Acceleration" is the speed that the CNC can accelerate from a dead stop to the working velocity, in inches per second per second. Depending on the settins of the CNC controller, power and stepper motor size, this number can range from 1 IPSPS to 50 IPSPS. For our machines we start out a 1 IPSPS, with accelerations of 25+ IPSPS being achievable.

Testing Computer Speed

Mach3 Drivertest.exe

If you notice a lack of performance with your CNC, or missed steps, you should run the Mach3 Driver test. It is located in the Mach3 folder on your harddrive and is called "drivertest.exe".

Loading the program you can set your parameter control (number of pulses Mach3 will send per second, for our Kickstarter electronics we use 35KHz), and press "Start Timer". The computer will then act as if it is actively sending out commands to the CNC and will measure how many are successful. If you computer is fast enough it will say "System Excellent" if your speed is too slow (or even too fast) it will say "Pulsing Too Slow" or "Pulsing Too Fast". Always turn off all other programs when running Mach3 (and the driver test).

Mach3 Tweaks

Mach3 General Configuration

There are many things you can set in the Mach3 setup "Config > General Configuration". Most of them should not be played with or adjusted. We have found one setting that is useful to change. Unless you properly tune your stepper motors it will be wise to change your "Motion Mode" from "Constant Velocity" to "Exact Stop". Your machine will accelerate to each point, and come to a stop instead of trying to power through each point. Using Constant Velocity often causes rounded corners, instead of cutting exactly what it is supposed to.

If you do use "Constant Velocity" mode, you can also setup an advanced switch between CV and "Exact Stop" by going to "CV Control" and activating the "Stop CV on Angles >" function with 45 to 90 degrees in the box. This will cause the machine to switch to Exact Stop when it approaches a corner that would otherwise be rounded off.