Milling Hardened Material

[Blaws]

Hello,
I am looking for some feeds and speeds to mill 6150 material that has been hardened to 60 R "c" on a Yasda high speed jig borer. We are using a 6mm 4 fluted carbide end mill that is coated. I can not find any feeds for materials this hard.

Thank you
Bud

 

[BillPSU]

You need to think grinding or using ceramics if available.

 

[jbel]

Check with the cutting tool manufacturer. They usually can give you a good starting point.

 

[CMfgE1]

I would suggest ceramic for this hard of a material.
Hopefully you already removed the bulk and are just finishing. If this is the case, using a diamond wheel for grinding or ceramic for cutting should do the trick.

You can also have carbide end mills coated with diamond using the CVD (chemical vapor deposition) process. This would be ideal.

With your current situation I would start with an RPM of about 2500 and lots of coolant flow. Keeping it cool is the key. If you have cold blast air system that would be better.
Just remember the key is to dissipate heat witht the chip. So play with the RPM until you achieve a good chip.


Good Luck!!!



Quote: "Its not what you know, its who you know"
Everythings a learning experience-Everything

 

[ornerynorsk]

Jig grinding. Hard maching is such a pain, you're asking for nothing but problems.

 

[Blaws]

Thanks for all the help. Sadly grinding would be absolutely impossible for the type of work. Recommended speeds for the YG1 Powercut mills are around 12000 RPM fed at 40 inches a minute. So I think I will move from that to a cbn endmill. I am hoping the cbn will run close to those parameters while generating a cooler chip. I will let you all know how it works out.

Thanks again...
Bud

 

[icrman]

That RPM maybe for something like aluminum.

For hard steel, you would be better off starting with
surface speed of say 50. Chip load determines the feed rate. And that maybe .001 if your lucky.