Calling All Highspeed Machining Guru's

[Tony35]

i have been playing around with this a bit and not having to much luck so any input would be great. i want to do this with soft materials (tool steels A2 D2 4140 303 SST)

couple of questions

 

1 how are you getting starting SFM

2 chipload

3 spindle speed

4 stepover

5 any other tips

 

i have been chipping out the tips of the endmills and burning them up plus i am not seeing any real cycle time reduction. i have the coolant off, no air blow machine does not have it(HMC so door open not an option). so the last job i did was 4140 with a 3/4 accupro 5 fl altin coated endmill @ 5000rpm feed @ 200ipm with a stepover of .03 multiple steps on the part from 1.1 to .17 deep (core mill and peel mill)cut fine on the first part but by part 4 the tips were gone.

 

so how are you guys going about this? max rpm? super high feed? where do i start, i must be missing something here

getting a tool guy in here is not an option

 

thanks for any input

[Fred @ Slate Industries]

Edit: Nevermind thought you were talking about hardened A2 not soft

 

I ran air through all of our machines Heads

Took some hand drilling through the spindle casting but its not in the way at all and "looks factory"

Turns on and off through Mcodes too.

[Jack Neelands™]

EDIT!!!!

 

 

First of all "I am not a Guru"

 

Should have put that in here before I answered the post

 

quote:

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i have been chipping out the tips of the endmills

 

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If you are using a sharp corner endmill for roughing you might want to look at something with a radius on the corner as this will take more stress and not prone to chip off....something with .01 or .02 max for roughing works well...the tool steels your talking about are rather abrasive in the soft state and tend to burn them off faster...then if you require a sharp corner ...chase it with a finisher.

 

 

Your feeds and speeds are about right for .008 per tooth and you can check them with this little calculator if you wish.

 

http://www.carbidedepot.com/formulas-milling.htm

 

If there was a way you could get air to clear the chip out would make a great improvement on your perfomance....

[Guest CNC Apps Guy 1]

Man, if at all possible heat treat that BEFORE machining. It's soooooo much easier. +1 on corner radii/chamfer tools. Sharp tools will kill you every time.

[Tony35]

quote:

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Man, if at all possible heat treat that BEFORE machining. It's soooooo much easier.

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so i could machine it faster in the hardened state then? better tool life?

 

not all of these parts gets heat treated

[dgriffiths]

This is what we are using to rough all of our stainless. This thing kicks some serious a$$. However we do use airblast when running.

 

1426 RPM

120 IPM

.040 DOC

65% Stepover

 

Mitsubishi

[Guest CNC Apps Guy 1]

Yeah, believe it or not you get better tool life AND better overall cutting conditions in the hardened state. Soft materials tend to gum up tools, generate excess heat and in the end cook tools. Whereas heat treated materials are less gummy, when using adequate air pressure the heat gets taken away from the tool AND the part.

 

HTH

[Tony35]

so its not all about the rpm but the feed? i have seen some videos on you tube (that i cant see at work ) with just crazy feedrates and spindle speeds so they are just burning up tools to make it look good

 

i have a makino a71 12000rpm and trying to get SGI on it so i can go faster i want to clear out some material when roughing thats where i can save some time.i can see i need to get air blast on it

 

maybe im not going fast enough?

S12000 @ 480ipm?

 

cnc apps guy

do you use inserted cutters or hybrid endmills?

i would love to try machining in the hardened state but to the guys on the floor "thats crazy" dumb programmer you cant do that it needs to be ground

[Jack Neelands™]

You have a Makino?...and your not machining hardened stuff?....WOW...just WOW....

 

Concensus has proven that to machine it hardened is the best way to improve tool life...not to mention ....WOW....just WOW

 

All kidding aside you need to chat with a reputable tool applications engineer that is in your area...most of the tool reps know of one or two and will send them your way if you request it.

[Tony35]

quote:

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You have a Makino?...and your not machining hardened stuff?....WOW...just WOW....

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ya i know thats why i signed up for a highspeed / hard milling class at makino here in wisconsin. i am going into this class blind thats why i am trying to get a feel of what you guys are doing so i can ask the right questions when i am there to try and get this highspeed thing up and running. we are very old school here and change is very hard for the guys on the floor "we have been doing it this way for 20+ years why change it we know it works" 2hrs later the part is finally done. with the economy the way it is my boss wants more work kept in-house (i do too more programming to do then) but we need to get things done faster to open up spindle time.

 

try this on for size...we have 5 HMC (1 HMC with 22 pallet pool)4 VMC and the guys on the HMC only runs 1 pallet! they say we only run 2-10pcs its not worth setting up the 2nd pallet. thats in my eyes what a waste.thats also part of my project to get fixed but i am starting with getting cycle times down first with faster machining thats where i am going with this highspeed thing

thanks for the input so far.. keep it coming this is ammo in my gun for my boss

[Rick Henrickson 65]

I would start with setup times, then move to cycle times just my 2 cents.

 

If you do a current state map on your parts almost always the cycle time is the smallest of the overall part

[Hardmill]

Check your mail tony

 

 

PEACE

[Jack Neelands™]

No disrespect but the head guys on the floor need to go see this too.....If you dont they will continually turn things down ..ie speeds and feeds and what not...sorry Its just the nature of the beast cause its going to scare the living $hit out of them at first....They are only trying to be safe ...so when they see hardened metal being cut like butter they are going to flinch ....or be gun shy if you wish and its going to take some time to get them to get up to speed..Give it some time and be patient...they will see the benefits when more work moves in and out of the door cause your quotes are more than competitive.

[Jack Neelands™]

Double post ....Holy $hite....WAS THAT A SIGHTING?

[Tony35]

quote:

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I would start with setup times,

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our setup times are really not that bad we have pin plates and fixtures with setup drawings its the cycle time...feeds and speeds and only 1 friken pallet at a time. when the cycle takes longer then the setup for 3 tools something is wrong here.(i know they are messing with the overrides and editing the prog but thats my bosses problem) thanks for the input rick im sure when we start setting up 2 pallets the time will increase. something to watch for thats for sure. the guys just dont want to give up the gravy... but with that attitude gravy is all they are going to get on the unemployment line

[X-L Engineering Corp]

Step over is important and corner radius

I use Jabro from Seco we use a .8mm to cut a .031/.033 x .130 depth slot and can hold a 20 micro works great.

[Tony35]

thanks for that chat hardmill

[Brian B 74]

OSG has a nice High Speed Machining Guide that I use as a starting point.

 

Highspeed Machining Guide

 

I use nothing but OSG in my high speed machining centers (OSG warehouse is 2 miles from my shop).

 

Air blow by far will help with your tool life.

[Tony35]

bbgun

thanks for the link

 

i use osg TSC drills

[Rob @ Target Machine]

[GURU OFF]

 

Good luck with this venture Tony. As mentioned earlier in this post, operators, and set-up guys will tend to override speeds and feeds unless you educate them. I'm trying to make this HSM thing work too.

 

My best analogy to HSM so far is heavy lathe roughing.... speeds - feeds - & doc are very similar. More heat goes into the chip, and less force on the tool.

 

This perspective helped me explain why this method works, to some of my peers, operators, etc.

 

I'm still learning this method myself though.

 

Just show this to the operators, and tell them that this could be considered as "Normal" in some shops, so they can thank you for not making sparks, flames, etc. LOL

 

HSM Iconel

 

[/GURU ON]

 

[ 01-29-2009, 07:53 PM: Message edited by: mastercamguru ]

[MotorCityMinion]

Plus 2 to radiused tools. Even if you have to follow up with a sharp cornered tool for cleaning up corners, finishing floors and holding tight tolerances will be much easier. Rpm? Max, assuming your tooling is balanced. Tool run out is very critical and cheap e-mills will run out. Heat treating for machinability VRS hardened to spec are two different things. I hate machining hardened D2 or M2. Looks nice when finished, but damn it eats the tools and it takes time to find the sweet spot between tool life and holding size. We have a Makino S51 with 20k spindle and heat shrink tooling and use Pokem, OSG, Nachi,and Kennametal e-mills (cheapest) for the the serious stuff.

[Rob @ Target Machine]

Plus 3.....the tool radius is a must!

[Tony35]

as for the tool radius...i did one job with a peel mill toolpath and it worked great so my boss orders all of the same style endmills with out letting me try out some other toolpaths on other jobs first. i will have to see if i can get some with a radius. im thinkin a inserted style maybe

[Tony35]

quote:

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I'm trying to make this HSM thing work too.

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mcguru

this is no doubt an uphill climb... but small steps and im sure we will get there.

[Guest CNC Apps Guy 1]

quote:

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...cnc apps guy

do you use inserted cutters or hybrid endmills?

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Roughing I tend to use inserted cutters. Finishing I tend to use Solid Carbide or CBN if I have 20k or more on the RPM

 

quote:

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...i would love to try machining in the hardened state..

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Good for you. No matter what, you should ALWAYS be striving to improve processes. Keep at it and don't let the dregs of the shop drag you down.

 

quote:

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...but to the guys on the floor "thats crazy" dumb programmer you cant do that it needs to be ground...

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Remember this one thing and you'll do well in life... "Start by doing what is necessary, then what is possible, and suddenly you are doing the impossible" St. Francis of Asissi (sp?)

 

ALL of what these guys are telling you is sound advise.

 

On occasion I have programmed the parameter change to disallow changing feedrate override, you may want to learn about that one.

 

I had to "do battle" with an insubordinate setup guy once. I'll just say that I know an awful lot about FANUC controlsand leave it at that... After he had ZERO control over a program I proved out he got the message.

 

DEFINITELY look at that link. Tell your setup guys to get an eyeful, then get in, sit down and shut up.