CHIP LOAD FOR SMALL CUTTERS

[Tinyfxds]

What are some general guidelines for SFM and RPM when using small cutters?  I'll be using a .062 carbide ball mill for finishing a drafted floor.  Max RPM on the machine is 12000 and the cutter only needs to be out of the holder by .100

[Guest]

Surfacing, you'll really be dictated by scallop height and finish required

 

There are several calculators that can help with stepover and resulting finish

[Tinyfxds]

I found an article in Modern Machine Shop that was suggesting no more than a 10% depth cut for roughing and about 1-2% chip load for finishing.  My RPM limits me on this one

[BillKobernus]

Feed and depth of cut depends on what material you are cutting and integrity of your machine. Your RPM's of course is gonna be as much of the 12,000 that you can go for a long period of time. We usually run about 11,500-11,800 on our 12,000 RPM spindle. ( OK so they are Haas. What can I do? That's what the boss buys.)

Rough Step over is usually .015 and .01 Deep.   Finish Step Over is .003      Feed can be as little as 5 IPM or less, if it's a small area that you are cutting, and I would go as much as 25 or 30 IPM in big open flat areas. It depends on the detail.

 

Good Luck.   Experiment.

[BenK]

There is too many variables to give an answer to this. What material, cutter, coating, machine and finish requirements? Look at the manufacturers specifications, it should get you close.

[Tinyfxds]

There is too many variables to give an answer to this. What material, cutter, coating, machine and finish requirements? Look at the manufacturers specifications, it should get you close.

 

That's why I said "general" guidelines.  In this application I'm finishing a cutting a floor next to a wall and I need the small diameter to finish the radius where the floor and the wall meet.  Mostly we cut aluminum but I wanted to see what people generally thought was a good starting point.

 

Feed and depth of cut depends on what material you are cutting and integrity of your machine. Your RPM's of course is gonna be as much of the 12,000 that you can go for a long period of time. We usually run about 11,500-11,800 on our 12,000 RPM spindle. ( OK so they are Haas. What can I do? That's what the boss buys.)

Rough Step over is usually .015 and .01 Deep.   Finish Step Over is .003      Feed can be as little as 5 IPM or less, if it's a small area that you are cutting, and I would go as much as 25 or 30 IPM in big open flat areas. It depends on the detail.

 

Good Luck.   Experiment.

 

Thanks!  We have Hurcos which I don't think are much better than Hass.  We have gone through 4 spindles in the 2 years I've worked here.  We don't dare push our spindles any closer than 2000 rpm from max, even for short periods of time.

[Guest]

 

Thanks!  We have Hurcos which I don't think are much any better than Hass.  

 

Let me fiss that for you  

[daryl_y]

From a job I just did a couple of weeks ago that was 6061 Alum.   .031 2FL carbide ballnose 13300 RPM,  20 IPM, .003 Stepover, the tool was just re-machining a couple of radii that was left behind by a larger tool.  The job was ran on a small 40 taper Mazak horizontal with a 14K spindle.

[Matthew Hajicek - Singularity]

Harvey has some recommendations on their website for their specific cutters in various materials and for a number of cutting conditions.

 

Did you see the article in MMS on micromachining?  They're using a 100,000 RPM spindle.

[BenK]

That's why I said "general" guidelines.  In this application I'm finishing a cutting a floor next to a wall and I need the small diameter to finish the radius where the floor and the wall meet.  Mostly we cut aluminum but I wanted to see what people generally thought was a good starting point.

 

I understood that but quite simply you can't give even a general guideline without having at least a minimum amount of information. Look through any cutting tool catalog and they state their recommended speeds and feeds, but not without knowing material. 

[Zoober]

With small cutters, you must minimize runout.

A small bit of runout can double (or more) your radial depth of cut on a flute or two. .06 is a fairly large cutter for us.

SFM is material dependent. But with 12k, chances are you will be low anyway.

I like Harvey's guidelines, although they are a bit conservative on the SFM. But hey, I like conservative.

[Brian B 74]

I use the OSG guidelines for most everything I do for 3D (regardless of cutter brand).

 

http://www.osgtool.com/_branding/books/80059ca-v5/80059ca-v5.html

 

 

[Matthew Hajicek - Singularity]

1st choice, find a recommendation from the cutter manufacturer.  2nd choice, use a recommendation from a different manufacturer for a similar tool, or plug parameters into HSMAdvisor.