The other place ramping seems to be quite important is in cutting a "higbee" thread. This operation follows the threading cycle with a grooving tool for the first thread, ramping out over one revolution to get rid of the sharp burr formed between a 60deg thread and a 45deg chamfer. I haven't actually made one of these "higbees", but have read about them and tried to figure out how to make them. Here is one explanation:
http://blog.cnccookbook.com/2012/06/16/programming-to-cut-a-higbee-thread-higbee-start-or-blunt-start-thread/ Lots of discussions on them on practicalmachinist cnc forum too. -- Ralph ________________________________________ From: andy pugh [[email protected]] Sent: Monday, May 19, 2014 2:06 AM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] Lathe Threading On 19 May 2014 08:27, Dave Caroline <[email protected]> wrote: > The ramps are essential for full strength as they remove the need for > a safety groove You don't need a safety groove anyway with a conventional threading operation, the retract move seems consistent. I am prepared to believe that a taper-out might give a better stress concentration as the change in stiffness of the bolt is less sudden. The lead-in and -out probably see very little use, but at the same time there doesn't seem to be any penalty for them existing as an option. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE Instantly run your Selenium tests across 300+ browser/OS combos. Get unparalleled scalability from the best Selenium testing platform available Simple to use. Nothing to install. Get started now for free." http://p.sf.net/sfu/SauceLabs _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
