speeds and feeds?

[mjs97]

i have been trying to figure the correct speeds and feeds for my cutters. im not sure im doing it right. could someone help explain exactly how to do this. i run steel and alum. usually 2 flute inserted cutters to rough and carbide balls to finish. sizes depend on piece. max rpm is 10000.

 

i was getting feedrates of like 150-300 ipm. i dont think my machine can run that fast and still hold sizes. if i slow feedrate down, do i also slow spindle down accordingly? trying to get max life out of inserts and tooling.

 

thanks

[K2csq7]

The best resource for feeds and speeds is always going to be the tool manufacturer. If you rough mild steel with a 1.0 tool, 300-400 SFM is a safe start point, thats about 1100-1500 RPM and if you go for .002" chip per tooth for a 2 flute cutter that would be only 6 IPM.

 

Welcome to the forum!

[neurosis]

i have been trying to figure the correct speeds and feeds for my cutters. im not sure im doing it right. could someone help explain exactly how to do this. i run steel and alum. usually 2 flute inserted cutters to rough and carbide balls to finish. sizes depend on piece. max rpm is 10000.

 

i was getting feedrates of like 150-300 ipm. i dont think my machine can run that fast and still hold sizes. if i slow feedrate down, do i also slow spindle down accordingly? trying to get max life out of inserts and tooling.

 

thanks

 

 

Wow. That is quite a bit of ground to cover with such a simple question.

 

What kind of Steel? What insertable cutter? Are you using separate insertable cutters for aluminum and steel? Different inserts?

 

Your not sure that you are calculating your feeds and speeds correctly? Are you looking at MFG suggested surface footage and chip loads for your specific cutters? It might even help to know what machine you are running this on? 40 taper? 50 taper?

 

You made your questions very hard to answer by providing very little information. Some specifics might help.

[mjs97]

sorry- heres more info. 99' haas vf3 cat40 spindle, millstar inserts steel shank bodies. different grade inserts for alum and steel. right now machining 4140steel, sometimes p20 or 1018. finishing i usually use .5 carbide ball unless i have to go smaller.

[neurosis]

So are you using Millstar's button style cutters or high feed? When you talk about 150 - 300 ipm is that in aluminum or the harder metals? I ask that question because we feed some high feed mills at over 300 ipm in 4340. NOT on a Haas however.

 

Does your machine have any high speed look ahead at all?

[mjs97]

millstar .5, .75, 1.0 button style. not highfeed. i was figuring alum., however not sure how to figure it exactly. machine has highspeed however no lookahead.

 

thanks

[neurosis]

http://www.millstar.com/images/Millstar_catalog.pdf

 

Do you have that catalog or an updated/newer catalog that has MFG recommendations?

 

Im not sure if you are questioning whether you are calculating your speeds and feed correctly or?

 

The catalog has all of your formulas toward the end and the recommendations on page 29.

 

If you are having issues with your feed rates have you considered offsetting the tool/leaving more stock for finish?

 

Generally when I am roughing aluminum with an indexable tool I run the spindle as fast as possible while trying to stay within the spindles horsepower range. I feed the cutter as hard as the spindle will allow. On our Mori its not uncommon to hit feed rates between 500 - 1000 ipm in aluminum depending on the diameter of cutter, radial and axial depth of cut.