So I’ve been talking with the odd person about machining CPM Magnacut on the S5P

The endmill recommended comes with the following specs from the manufacturer

Tool Steels > 36Rc (A2, D2, S7) SFM min:250 max:350 Feed per tooth 0.0017

It’s a 1/4" 4 flute flat endmill

you get the 20 inches per minute from the IPT (Chip Load) (Chip Load) = IPM / (No. of Teeth x RPM)

so the mill has 4 teeth at 3000 rpm we get 20ipm or 508mm/m

508mm * DoC * 6.35(diameter) should equal less than the maximum materal removal per HP (1cubic inch per HP per minute or 16,387.064 cubic mm)

16,387.064/ (508 * 6.35)[3225.8] = 5.08mm DoC at 1hp

at those feeds and speeds we get a DoC of 4.8mm for a 1hp spindle BUT I figured this may be too good to be true and it appears that the math behind it is anything over 1800rpm is linear decline at the shaft on a VFD spindle:

1 HP=(RPM * T) / 5252 which is like 1hp = (18000.3) /5252

which at 3000 rpm is .171hp = (3000*0.3)/5252

unless I’m mistaken somewhere 5.08mm * .171 = .86mm max and .69mm slotting DoC to get the required speeds and feeds for semi optimal longevity on the endmill (for this material optimal longevity on a semi rigid machine would be 500 minutes of use but on this I’d be happy with 120)

Then there’s the question of the rigidity of the machine. Would I want a lower to the bed low profile fixture or would I want a raised but well supported heavier fixture that would bring it closer to the gantry to reduce chatter.

Obviously airblast is a must to prevent chip welding which I’ve been told since its annealed won’t be as bad as hardened but still a must

I’m unsure if I’m missing any factors, miscalculated anything or if this is just a stupid idea but would love some input and knowledge from those more qualified than myself.