Feeds and speeds. Some tips for a newbie please!

[Chaz]

I am looking for a little guidance on feeds and speeds with a 2kw 3040 size gantry router (not chinese - this one has 20mm hiwin linear rails).

I want to take a light skim over a large area of ali plate. (no idea what grade it is).

So after googling about and looking at the feed and speed calculator on littlemachineshop's site, it appears that if I am using an HSS 12mm 4 flute endmill, the spindle speed should be very slow at 1600 rpm and the feed also slow at 275 mm/min.

Switching to a carbide endmill, a much higher spindle speed, 7200rpm and much much faster feed of 2800mm/min.

Does that sound right?

I have seen people using very fast spindle speeds and feeds (16k prm, 4000 mm/min) but not sure with a 12mm cutter?

Any general advise regarding this topic?

Obviously lube/cooling comes into play here, but initially I would like to run the machine dry or with a minimal mount of lube.

I am looking at taking a very shallow cut as I am just getting the plate flat, so no more than a 0.1 or 0.2mm cut.

Any advice welcome.

Cheers!

For me, Id run max spindle speed. So 24K, Id start with 1500mm/min and work up from that. For shallow cuts you can probably go faster but 1500 - 2000mm/min is decent. How accurate do you need and how much material are you removing?

[Richard]

For me, Id run max spindle speed. So 24K, Id start with 1500mm/min and work up from that. For shallow cuts you can probably go faster but 1500 - 2000mm/min is decent. How accurate do you need and how much material are you removing?

Hi Chaz,

24k rpm and 1500mm/min, sounds crazy fast! (comming from a manual knee mill!)

Only a 0.1mm-0.2mm cut.

How much slower would you go with an HSS cutter of the same size?