I'm new to milling aluminum. I'm ancient history in CNC operation. I remember the first wooden bit. lol Been searching for 2 months finding info on Speeds & Feeds for milling aluminum. Found 6 calculators, downloaded 3 programs ..... and not even one matches another's recommendation. This is getting sooooo old. This whole metal cutting speed and feed calculations is atrociously confusing. And then after I did all my research I keep reading that most have to experiment to find the "sweet spot".

I'm braking bits like there's no tomorrow. Someone please get me to a base setting where I can just cut my parts and get this whole metal thing done and I can go back to my wood projects. I don't need production speeds. Just a setting where the bit doesn't break and it doesn't travel at sloth speeds.

The confusing part is that HMS advisor has input parameters that contradict what I've used on wood. I have an RPM a Table Speed and a Plunge rate. Why does HMS have 2 feed categories in the Speed and Feed box? Way too confusing. It keeps giving me a 33K RPM???

Equipment: EZrouter 5'x12' table. 10hp Spindle motor is up to the job and then some. Gantry system same. Auto load tool. Vacuum table hold down. Torque is not an issue.

Cutting 6061-t6 1/4" & 1/8" plate.

Using a ("diamond like") coated 1/8" end mill 1/8" shank 3 flute 3/8" cutting length 3/8" protrusion from chuck. (Their spec's = 18k rpm 14 ipm 'not working')

Cutting out triangle and square shapes (mill cut) Perimeter cuts leaving 1/16 tabs on all sides to prevent dust vacuum from lifting parts after final cuts.

Getting very small chips. Approx 1/6" in length at 10k RPM 45 IPM .016 DOC 3.5 IPM plunge. Continuous air at bit with very fine tap fluid spray. 15 passes to cut 1/4"?? Driving me crazy watching something go that slow.

When I get to a 90 degree corner it's a guess whether bit breaks. So I exploded all my objects to single line cuts. Still get occasional breaks when cuts are diagonal to X-Y.

At this rate I'll be done in September because my table edge stop system is at +.75" and I have to use a 1" Z clearance setting. Up and down at 3.5ipm for every .016 cut. And I'll have $500 in bits. And the bit coating stops a good touch off for 0 'Z' so I have to paper set for Z every time I break a bit.

Any help is greatly appreciated. Thanks.