PCB plotter - Prepare a PCB for etching with your 3D printer

This is a remix of the 2D Pen Holder used to hold a metallic rod and engrave PCB image before etching as shown here:
https://hackaday.com/2015/06/29/etching-pcbs-with-a-3d-printer/

Note that we made quite good PCB using that technique but we do not like the slight force it gives on the printer head.
We are now remixing that object to hold a laser instead of a rod.