PCB Engraving / Cutting

[wiatroda]

Am I better off using an end mill or ball nose?
Any other suggestions?

Nice tank, It reminds me my adventure with cichlids few years ago.

To produce PCB I use carbide CNC PCB engraving bits. I bought them from http://www.virtualvillage.co.uk/3-x-1-8-carbide-cnc-pcb-engraving-bits-tools-machine-007807-075.html?utm_source=googlebase&utm_medium=shcomp - best price I found so far.I can't tell you how long they will last. Mine still works fine.

My first ever PCB cut with those bits:
http://www.mycncuk.com/forums/showthread.php/3338-My-first-ever-CNC-cut-PCB
How many PCBs are you going to produce??
Hope that helps

[Jonathan]

Shank is the right name.

The best way to do it is to use a sufficiently small diameter endmill. The good thing about and endmill is the depth of cut does not matter, unlike a V-cutter which requires the PCB to be flat to maintain a constant isolation gap. Also and endmill may well have 2 or more flutes, so you can cut faster.

I've used V-cutters in the past - use about 60mm/min feedrate per 1000rpm spindle speed. So for instance a 24000rpm spindle gets 1440mm/min. If you go faster you might leave burrs.

The PCB you're making looks extremely simple - the isolation gap is large. That's good since you can use a relatively large endmill and thus feed it faster.

I posted about it here:

http://www.mycncuk.com/forums/showth...ll=1#post21637

I use a 2mm slotdrill to cut out the PCBs:

http://www.youtube.com/watch?v=vDNScafwTYw

(The spindle speed on the mill is only 2150rpm,hence the slow feedrates)