I perform several break-in operations on every machine I build. These operations vary from moving the machine to its extends to performing complex drawing or machining tasks.

Types of Break-in

Lets take a look at the various types of break-in that I use.

Basic Break-in

The initial (basic) break-in test is used to help the machine get into its groove so to speak. It helps to loosen new fittings and to shake out any early fastener issues.

The “Basic Break-in” is a simple loop that takes each axis to its extents.

CNC construction set break-in files:

In order for these files to work you need to position the machine at X:0 and Y:0 (Front left) and zero the X and Y axis. The Z axis needs to be zeroed near the bottom as the tests need about 3” of travel.

I run the slow test for about 4 hours, then move on to the medium, and then the fast test.

Here is the three tests in action. Note that once I finish with the tests, I go back and check each axis for slop.

I also use the break-in files when I oil the drive screws and linear rails.

Drawing Break-in

A drawing test can help you really shake out issues. You don’t need a spindle for this test, a simple pen holder will work just fine. You can get some information on making your own pen holder here: DIY Pen Holder

This is a drawing test I use to put my machines through their paces.

I run this break-in at a slow 100 ipm with the acceleration on my motors set low as well.

The test takes a little over an hour.

I have index marks that are drawn at the beginning and end of the test. If any steps are lost it will show up here.

After I do the initial run and make any needed adjustments, I will up the speed and acceleration until things start to fail.

Here is an actual run I did on one of my machines. You can download the drawing files I used as well as the gcode here:

House Drawing Files

Other Drawing Tests

Acceleration Truck Test


I use this file to test the machines stability during high acceleration.

You can find the drawing files here:

Acceleration Drawing Files

This is a very early CNC Construction Set prototype. By performing this test, I quickly found out the stand I was using would not be suitable for plasma cutting.

Some other Tests

Here is a break-in of one of my KRMx02 machines.

Here is a Z axis break-in that I have used to test my Z-axis.

Z Axis Test

I used the Z Axis test file to help me pinpoint and diagnose a bad set of thrust bearings.