Milling: creating a smooth end finish in a slot

[Robin Hewitt]

Obviously I know nothing because I have no machine tools that do tens of thousands of rpm, someone will be along to tell me off in a minute, but I would happily cut that in modern brass. When I was a boy, back in the mediaeval period, brass used to snatch but those days are gone.

I think your problem is you are rubbing rather than cutting.

Slavish adherence to achieving feet/minute cutting speeds with tiny tooling makes for ridiculous rpm.

Keeping the tool shank intact with ridiculous rpm leads to tiny DOC.

Trying to get a job done in a credible time frame with tiny DOC leads to high feed rates.

I like my brass to be on the verge of squealing when I cut it and give a nice flake. I would use HSS tooling because a sharp edge is more important than tool wear, there is no tool wear in brass. It cuts like a dream unless you have that mediaeval brass which is a bitch.

I just looked up your router, it has 30 microns of backlash. That is not bad, but does it support a 6 micron tooth loading?