New to site, Need help with Inconel 625.

[Erik F.]

I'm face milling two .375 thick by 15 in. long pieces of inconel flat bar. I need to take them down about .500. I have a old comet mill and minimal milling experience, I have been using a 3 in. indexiable with square carbide inserts. I'm sad to say that all my experience is with lathe work and im pretty much clueless, any help would be greatly appriciated. I think my biggest problem is the interuppted cut? I keep breaking inserts.

[speedtwin69]

I would try some Hanita Varimills, thats is all I use at work they seem to work pretty good. Run them at a moderate pace.

[R&Rmachine]

Need a little more info, what kind of machine? How wide is the part? Inconel is hard you have to manage the heat generated by the cutting op you have to make the chip carry the heat away In order to do this you have to feed hard and reduce spindle speed a face mill will work, but
It will have to have a lot of teeth a better choice would be a short rigid .750 end mill

[crabbass]

high positive sharp tools work best, If your facemill uses positive square inserts with a 45deg. lead angle... you are off to a good start. Good quality coated carbide(like Altin, Tialn.) will only allow about 100 SFM cutting speeds. Depending on your setup rigidity, and machines horsepower, you can determine depth of cut and chip load. In a nice #50 taper machine you could easily cut .25" deep with a .004 chip load per tooth. In a bridgeport style knee mill you could probably only cut .05" deep with a .002" chip load per tooth.
I agree with speedtwin69... for periphery finishing the varimill by Hanita is excellent!!