On 02/14/2012 11:04 AM, dave wrote:
> On Tue, 14 Feb 2012 11:07:05 +0000
> andy pugh<[email protected]>  wrote:
>
>> On 14 February 2012 09:09, Mark Cason<[email protected]>  wrote:
>>>    Can anybody recommend what type and shape of insert to use to
>>> turn a 2" piece of pre-hardened 4140?
>>
>> How hard is it?
>> I have found that harder steels give a better finish anyway, and with
>> a small cut and a huge surface speed CBN tipped inserts work nicely.
>> You probably want to use a tailstock for rigidity.
>>
>> Look at Youtube for examples of "hard turning" and eBay for
>> individual inserts.
>>
> Kennametal recommendation:
>       <  Rc 48
>       fine finish
>       KT315 85 degree insert
>       -11 very fine finish -uf fine finish
>       starting conditions 680 sfm  ( range 600 - 900 )
>       0.0015 - 0.006 /rev
>       doc .003 - 0.03
>
> right out of the Kennametal "lathe tooling"
> a useful book to have on the shelf.
>
>  From what I can tell CBN works very well above Rc 48 but I have no
> experience.
>
> Dave

   Thank you Dave, I downloaded several catalogs from them.  Interesting 
reading, more than I can absorb in a day :)

-- 
-Mark

Ne M'oubliez   ---Family Motto
Hope for the best, plan for the worst   ---Personal Motto


------------------------------------------------------------------------------
Keep Your Developer Skills Current with LearnDevNow!
The most comprehensive online learning library for Microsoft developers
is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3,
Metro Style Apps, more. Free future releases when you subscribe now!
http://p.sf.net/sfu/learndevnow-d2d
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users

Reply via email to