Hello. calculated speeds and feeds assume machinst is using proper coolant for application. IE. for aluminum flood coolant is assumed. same for magnetic steels below 25RC and at sfce speeds below 450 SFM When machining hardened steels or any steels above 450SFM coolant is not advised. Contrary when machining stainless steels, titaniums and hi-temperature alloys coolant is generally recommended. But again even in the last case when using hi-speed tool paths and running at high SFM coolant is not advised. its more of common sense and experience. hard to put everything into formula. but

I wondered about that too recently.  Our shop has moved to some 4140annealed recently.  We have been having a bit of a rough time.  None of us have cut anything this hard before.  We have been attempting to side mill with a .5" TiAlN-coated chipbreaker from Montser @ DOC.42".  I have read a great deal about NOT using coolant with coated endmills like that, but we always have in the past.  The point is I feel like no coolant should mean some adjustments to feed and speed rates.  I am curious about how to account for that if the endmills actually cut better with some heat.  Any suggestions or insights? Steve S AmendmentArmsInc

I would also like to add a "thank you!" from all of us  at the shop! Steve S AmendmentArmsInc

  Hello. Thanks for the kind words. My calculator assumes PROPER cooling and chip evacuation. For aluminum flood coolant is assumed. For tool steels air blast to remove chips. If you are cutting any heat-treatable steel with carbide tooling you have two choices- go very slow and flood it like crazy, or go fast and cut dry. All of the tool manufacturers of HPEnd mills with TiALN coating give speeds and feeds for dry cutting. There are several reasons to that. 1) TIaLN coating needs certain temperature to work properly. 2) When cutting tool steels alot of heat is generated in the cutting zone. Coolant thermally shocks  carbide which causes micro cracks and subsequent tool failure. 3) When hot chips contact coolant they harden and if they subsequenly get re-cut, they easily damage cutting edge. All of it means that Generally it is not a good idea to use coolant when cutting tool steels at above 200 SFM or so By the way, We tested WIDIA's Metal Removal Maestro HPEMS along side Monster Mills and Monter Mills are cheap, but they last 30% of what other endmills do. Like i said before i will try to push forward some sort of "Tips" system that wuold advise on best use of coolant nad coating in relation to the material.

<!--StartFragment -->Maybe you could add a "coolant" that turns green or grays out depending status of coolant in your calculations. Maybe the same for "Air Blast" David  

Do you wish to be able to choose what kind of cooling you are planning to use, or you want to see some sort of suggestion popping up and telling you whether coolant is recommended or not? I am asking because things like that involve alot of fuzzy logic and may not bring enough return for the effort.... You can read a post on top of yours explainging the logic behind using or not using coolant.

I like some sort of suggestion popping up and telling you whether coolant is recommended or not?

I will see if its worth it. If i get to do it it will be inside a bigger help system that would recommend on many more things than just coolant. Thanks for your involvement. Drop me a line if you have suggestions or bugs to report.