New to high speed machining

[MGIRLING]

I have been visiting this forum for the past couple of years and have gained a vast amount of knowlege from you guys but have never had to ask a question before. I have done some searches on this topic and still don't feel like I have good grasp on the feeds,speeds and depth of cut involved when high speed machining. My compay is looking at buying a new Hurco VMC. We currently run two Hurco's that are getting up there in age. They both only have 4000 RPM spindles and slow feed rates. I was just informed by my boss that I need to program a small sample block of S-7 (46-48 Rockwell) to send to the machine tool salesman for a test cut and I have no idea where to start with my feeds and speed as well as my depth of cut. The new machine we are looking at has a 12 hp 10,000 rpm spindle and is capable of 600 IPM feedrate. I have looked at the charts for the Garr (TIALN coated) catalog and my calculations dont seem to get the feedrate up anywhere near the high speed range. Any help would be great.

[Tony]

Sir

 

It goes to 10,000 rpm BUT you cannot run it there.

These machines are sold as "High Performance"

Not "High speed" as I'm sure Dana A.

pointed out....?

What are your goals with this machine?

 

 

Feel free to E mail me

 

Tony

VMX30,VM1

 

[ 10-24-2003, 04:24 PM: Message edited by: Tony ]

[MGIRLING]

We are a small mold shop and our goal for this machine is to allow us to use smaller cutters and reduce the number of electrodes we are currently producing and of course speed up our cycle times. I'm not sure who Dana A is?

[McRae]

Testimonial case from the Sandvik Lit-Sup-T/R00.2 pg 153

 

Material - Steel 55HRC

Vc (Ft/Min 395-920)

Dc (mm - 10 or 0.394")

S (rpm - 8915)

Feed/Tooth (0.002")

DOC (mm - 0.5 or 0.020")

WOC (mm - 0.5 or 0.020")

Speed - 39ipm

 

This example is for a copy milling example. The surface finish in this example is critical as well as the tool life requirement.

 

Based on your question - what you should really do is ask the Machine Tool Applications Engineer to do the home work for you and "Show" you what the machine is capable of and not just "Tell" you that the thing will do 600ipm.

 

I will argue with anyone that thinks they are achieving an actual speed of 600ipm over short distances and changing directions in a surface milling application. Don't focus on the feed rates - focus instead on the accelerations and look for something that will pull serious "G's"

 

Good Luck and look to OSG, Sandvik and some of the other High Performance Tools for help here - throw away all those side lock toos as Balanace and vibration are you new found enimies.

 

That's all I have for a Friday pm - so good luck.

[Rekd™]

+1 Andrew, as usual.

 

It's a 'G' thang!

 

If the trodes you're looking to replace are small, with anything less than a straight surface, you'll need to pull more Gs, not run faster. Getting to max IPM over a 1" area and around a corner accurately is the hard part. Any machine can run balls out at the max IPM in a straight line.

 

I look at it like this... any tires will take you up to speed and keep you there with minimal turns, but you need slicks to wrap around a 45 mph corner at 120 mph.

 

 

'Rekd

[MGIRLING]

Thanks for the reply's. Gotta run (It's Friday) I will check back on Monday

 

Thanhs again

[Chris Rizzo]

quote:

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you need slicks to wrap around a 45 mph corner at 120 mph.

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and knee pucks!

[Harryman]

quote:

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you need slicks to wrap around a 45 mph corner at 120 mph.

---

And a huge dent in the tank to make room for the BOYS.

 

Rapid directional change IS acceleration. Precision under high acceleration is another topic. Sounds like you need both.

[Brendan P]

CMR,Where is your avatar??

You are overdue!

[crazy^millman]

Well I am going to be going to this land if the 2 machines we are getting and they claim to be. I to be honest want ot see the proof in the pudding so to speak. I will be pusing these machine to their limit and have already stack 8 jobs up for them. I will be pushing a 1" button cutter at about 400 ipm at 12,000 rpm with a .100 depth of cut of some complex surfaces in 6061-t6 to be nice to start with. I know the tools will handle it but will the machine. I figure it will take 2 hr 30 minutes with what I got know and feel I can get it down to 37 minutes per part on this operation if these machine can walk the walk that they talk the talk about. I will either be Haas New best freind or become their worst enemy. Time will tell and don't thin kthey like me saying I am not signing off till I get to run soem laps wit hthe machine. I start my books on the machines the day they hit the floor and will go from there. Sorry to highjack your thread there just felt like throwing my 2 cents out there is all.

 

 

Crazy Millman

[Guest CNC Apps Guy 1]

I'm with those guys. High speed machining isn't just about High RPM and High Feed Rates. It's a whole other approach to removing metal but 10k RPM is about where it starts (JMHO of course).

 

The material you're going to cut plays the largest single part in how you approach it also. Hardness is not really the issue - I've machined up around 58 Rc personally and I've found the material properties tend to be more of a consideration than hardness alone. You'll want a machine that is able to process blocks very fast, alter feed rates to maintain accuracy. I don't believe Hurco is your machine if you're serious about HSM. You need to be looking at Makino, Mori Seiki, Mikron/BD, Yasda, etc... Even used machines of that calibur would be a wiser consideration IMNSHO.

JM2C

[DavidB]

James also i think the controller you have on your machine is very important i ran a Fanuc 16I M and are very happy with its HSM capabilities.

[cadcam]

quote:

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Fanuc 16I M and are very happy with its HSM capabilities.

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+1 in the Fanuc seris this is a good control for this.Us them on the Yasda's.

[Guest CNC Apps Guy 1]

Yes, yes, of course. Fanuc makes a great HSM Control. They also have a new option called iAdapt. This essentially slows the feedrate down when heavy cuts are encountered. Fanucs are great for writing posts for too. Straight forward code with format changes. Plus, you can DNC from an SRAM card or if you want you can get a DataServer.

 

JM2C

[Rekd™]

quote:

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And a huge dent in the tank to make room for the BOYS.

---

LoL!!

 

[hi-jack]

The 'boys' are the reason I bought my TL1000..

 

I got 'asked' to ride it while shopping for my wife's bike.. (they were tired of me yelling at them about trying to sell her a 600 so wanted to get rid of me for a few minutes.)

 

I was on the bike for 35 seconds and smacked the 'boys' on the gas tank after a completely un-expected roll-on wheelie. So I limped back into the showroom and bought it. (the wifie got my old GSXR750)

[/hi-jack]

 

'Rekd teh nickel plated jock strap

 

[ 10-25-2003, 07:33 PM: Message edited by: Rekd ]