Fan Vent

Overview and G-Code

Cabinet with fan vent
Cabinet with fan vent.
A fan is often needed to vent the control box so the drives and power supply do not overheat.

A computer case's cooling fan works well.

A round hole will work, but a decorative port looks nicer, even on an old recycled case like the one shown here.

Note that an exhaust outlet elsewhere on the control box is also needed.

This code is for thin stock such as the counter top laminate (e.g. Formica) shown here.

The g-code is linked at the bottom of this page.
The g-code cuts the perimeter of each hole in one pass at −0.1 inch. It is for a 1/4 inch or smaller straight bit.

The top of the stock is Z at zero, and the bottom of the cut carves into the bed at −0.1 inch (negative 0.1 inch). The clearance plane is 0.125 inch.

X zero, Y zero is the center of the fan.

The total cut is ~3 inches in diameter, but can be scaled in the controlling software for different diameter fans.

The leftover stock from the cuts may be grabbed by the router bit. Use a vacuum or compressor to move the scraps out of the way. Do not use (lose) your fingers for this.

Fan Vent
CNC cut fan vent.

A spoil board that is secured underneath the stock is recommended.
The codes have been simplified to only use G01 moves. All arc and circular motion is broken into short line segments. This is done so the codes can be used with basic controller software.

These short segments will cut more smoothly with constant contour activated. (G64 in Mach)
The first three lines of the code may need to be deleted with TurboCNC.

Disclaimer: These codes have been tested on my CNC systems and have worked well.

You assume all risk and responsibility when using them.
G-Code           Fan Vent G-Code