You Can't Take Fine Cuts With Tungsten Carbide Tooling

[Magicniner]

I snapped this as I was clearing up and remembered that this thumb-full of swarf was the result of an impossible, sacrilegious and deeply discourteous cut that I'd taken yesterday, without any regard to those who see this kind of thing as deeply disturbing and not to be attempted, to finish a part in Silver Steel.
I was running at 2600 rpm using the general purpose insert I've recommended here in another thread and, the cut was .01mm (around 4 thousandths of an inch) the part was blued and shipped by the time I cleared up but the finish was nice and worth blueing without needing a polish first,

- Nick

[SteveHGraham]

Photoshop!

[tornitore45]

0.01 mm ~= 0.0004"

[Magicniner]

0.01 mm ~= 0.0004"

Good call!
4 tenths, not 4

[BadDog]

I've never personally encountered a carbide insert that could reliably cut to under half a thou in steel. IIRC, "silver steel" is what we call carbon steel, or a mild tool steel? And I'm assuming that's actual DOC, around 0.008 off the diameter? I have done it with cermets, but never with carbide. Not that it wouldn't be possible, but not with the inserts I have, not even the very sharp highly polished ones I reserve for (and are made for) aluminum.