Skill Builder: 4 Axis Mill Setups for Round Stock

Create CAD Model

Start with simple solid models, nothing fancy.  I’m using a cylinder with some holes in it, made in Vectorworks for this example.

Export as an .stl file.  And save to a thumb drive.

Basic 3D Model Skill Builder found here.



Always wear eye protection when operating the 4 axis mill.  Never leave a running job unattended.  The emergency stop is located at the front of the machine.


Upload in Roland Viewer

Open Roland Viewer and upload your .stl file.  Run through the software options


Model Size and Orientation

You can resize your work here.  You will most likely need to reorient your model.

Type of Milling

Select the type of milling, for now choose “Faster Cutting Time”.

Then select if the model has more flats or curves.

Then choose if you are cutting cylindrical or block material.  This is where you can add tabs to the part.  In this example, I did not add tabs.


Create Tool Path

Choose the material you are cutting.  If you are cutting delrin, ABS works great.

Enter in the size of your material that you are cutting.

Then click “Create Tool Path”.  This may take a few moments.


Preview Results

If you are not happy with the results, bit selection, or the length of cutting time, you can edit the tool paths.  This video gives a detailed description on how to do this (at the 6:20 mark).



Prep Material

There is a lot of waste material for the 4 axis mill, make sure your stock material is the proper size.  Measure your material as accurately as possible.  It is a good idea to write it down.

One end should have a center hole drilled.


Load Material

Similar to the lathe, the material is secured in a “chuck” and a live center is put in place using an allen wrench.


Set X  and Z Origin

NOTE: You will only be setting the origin of X and Z (in relation to tool length), not anything else.

Open VPanel for Modela Pro II on the workstation.

Click “Base Point” and jog to your X origin.  Y and Z axis should be set correctly in relation to the turning axis.  Do not override these values.

Select “Set X Origin” and Apply.

You have some wiggle room, but X origin should be just to the right of the end of the material.


Before you set the Z, you must make sure the Z-Origin Sensor has the cable plugged in and is clear of debris.  Your bit must also be installed in the spindle.

Click on Apply for “Set Z Origin at Center of Rotation”.  Note: the CNC will move after you click apply.

Screen shot

The bit will come in contact with the Z-Origin Sensor, and set Z.  If you need multiple bits for a job, you will have to reset Z every time you change a bit.  Never reset X during a job.


Perform Cutting

Confirm that your bit length is long enough for the job.  This means measure how much of the end mill is sticking out of the spindle, if it is the length specified or longer, you are good.

Confirm that X origin is properly set.  You do this in VPanel.

Click “Start Cutting”.

Most likely there will be a Roughing and a Finishing pass.

You NEVER leave a run machine.  You can pause the machine in VPanel.  Clicking “Pause” pauses the movement of the cutter, but not the spindle.  Clicking “Stop Spindle” pauses the bit from turning.  Clicking “Resume” will continue the job.

If something goes wrong, most likely the machine will throw an error.  Unfortunately, the only way to start back up is to power down the mill and restart the job.

If this has happened, you most likely chose the incorrect material.


When complete, clean up the area and remove your material.  Leave the bit in the spindle.