[Graphicman]

Attachment 266550

This is one of them done with the single flute bits 30 degree carbide cutters.

The 3 flute variety wont cut as nicely as the single flute because the cutting edge angles arent as sharp, I think these may work well in very hard materials maybe, I dont know as I have never used them. the three flutes would be better as you could raise the feedrate as it has 3 flutes instead of 1.

Everything is a trade off, shallower angles on the cutting edge will make the tool last longer but it wont cut as cleanly and will take more spindle power, sharp cutting edges are the opposite etc

I use these single flute cutters to cut from .010 to .060 depending on what I am using it for.

thats very interesting
however i still feel lost because there is now at least 4 completely different types of engraving bits,
the traditional ones like the Kyocera, pyramid bits, pcb engraving and the single flute bits you are using
add to the list those new carbide inserts, i have seen them even locally but they are very expensive (no idea what is the point then!)

it would be good to know what every bit is designed to be used WITH (even the manufacturer never tell anything)

https://www.youtube.com/watch?v=dx-ndeBo8Ng
please take a look at that video, I have no idea what this cutter is (the engraving one) but it seems from its geometry (if you can pause the video on the right time) like the one you are using,

by the way did you ever tried to engrave deeper using these cutters ?? it would be very interesting

I still dont think the multi passing is a good idea for the tip life