Please do not understimate the accuracy of a cnc machine when used to realize a pcb. If a machine is well done, without any backlash, the accuracy of the milling procesh could be really astonishing.
On the image on the top you can see a small test, in millimeters, of a milled pcb. As you can see even a 0.25mm tracks can be really well clean-cut
The small test has been realized using a micro-ball (0.15), showing a few tracks in ascending order.
Consider that it is really difficult to find on the market economic micro 2 flutes end mills but it is quite easy to find (chinese origin) economic micro-ball end mills or vgrove end mills. Very probably these end mill are created for low-end jewelry but they respond to our needs even if such a mills need to work at low speeds.
Naturally there are end mills just created to realize pcb:
In the picture three different end mill are shown:
- a 0.6 mm drill bit;
- a single flute Vgrove for scoring (0.2mm);
- a Vgrove single flute end mill:
- a 2 mm for pcb cutting
