PM End Mill Question

[J. Coe]

Anyone have any recommended SFM parameters for using a 1/4" 4-Flute powdered metal end mill in AISI 1018 material, mostly for slotting?

 

Thanks

[crazy^millman]

400 to 800 sfm and anywhere from .002 to .008 per rev feedrate.

 

HTH

[Rick Henrickson 65]

75 - 90 sfm .0012 feed per tooth

[Guest]

quote:

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400 to 800 sfm and anywhere from .002 to .008 per rev feedrate.

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quote:

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75 - 90 sfm .0012 feed per tooth

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Now THERE'S a difference of opinion for you

 

[jeff]

That's quite a difference between Crazy's and cascadeclimbr's speeds

 

edit: John teh too quick

[kccadcam]

quote:

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400 to 800 sfm and anywhere from .002 to .008 per rev feedrate.

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That's where I would start.....

90 sfm with Powdered Metal in mild steel???

WAY to slow.......

[Rick Henrickson 65]

i just took it out of the cleveland catalog under

pm plus / cobalt speeds and feeds section

 

there isnt anything other then aluminum that is over 400 sfm

[crazy^millman]

Powered Metal is the same a carbide as far as speeds and feeds goes IMHO. I really like the drills for Titatium. They have the give, but the stregth as well as durablility to do a good job. Should be real happy with that is CRS.

 

HTH

[J. Coe]

Thanks for the input guys. The reason i'm looking at Powdered Metal is because I'm having a hard time running carbide mills (small diameters) due to breaking. I do good to get half a manufacturer's recommended feeds (even on CRS). I have a 40 taper machine and recently bought some Kennametal short collet chucks to try and reduce tool length. Those didn't really help. I'm still getting some flex somewhere. I believe this flexing is also causing the larger diameter carbide mills to wear prematurely too. Oh well, we'll see how this pm end mill works in the meantime.

 

Thanks again for the input.

[crazy^millman]

Are you checking runout on the tools? Are you checking to make sure the taper holders are sitting right in the spindle? I would also check to make sure you are getting good chip clearence on your cuts.

[J. Coe]

Crazy^Millman: Yes, I have checked the runout and everything seems to be in order there. As far as chip clearance, I can't get the tool to make it that far in the cut. For example, I put a Hanita 3/8 Carbide 4-flute end mill in for a cut and as soon as the mill finished the plunge, it snapped immediately when it started it's linear movement. I did find that i was forcing too much coolant into the cut and not letting some of the chips out, but i have tried dry cuts and also cuts with a minimal amount of coolant flow which both helped but still not enough. Right now I'm running a 1/4" Hanita 4-flute Varimill in CRS at 10 ipm with axial d.o.c. at about .150". Even at this rate, I'm still getting some slight flex when the mill changes direction.