It's pretty unlikely, but with the first pass being free of humps I'd be tempted to look at tool deflection. If your first pass is milling in from fresh air it'll take a lighter cut, the heavier (and more consistent) cut on each subsequent pass could then be deflecting slightly.
If this is the case, and you don't find a better solution - you can always do the cut in two passes, cut it 1-3 mm undersize then do a quick finish pass to cleanup. Not ideal, but I tend to have to do this with smaller diameter cutters on my non-rigid router. Your sub looks OK, but I'd also be tempted to use G2 I J Z P directly to rule out any... odd motion planning. Ben -----Original Message----- From: Igor Chudov [mailto:ichu...@gmail.com] Sent: 25 September 2012 21:31 To: dengv...@charter.net; Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] Helical interpolation not quite round, WTF? Humps are 1) Northwest corner, biggest hump, 1mm tall by 20mm wide 2) Northeast corner, 0.5mm by 15mm wide On Tue, Sep 25, 2012 at 3:08 PM, dave <dengv...@charter.net> wrote: > On Tue, 2012-09-25 at 15:13 -0400, Stephen Dubovsky wrote: > > How big are the "humps"? How many are there? > > > > Are you in exact stop mode? If motion stops at the beginning/end of > > each semicircle then you will get a little hump from springback > > during the pause. Lead-in & out are typ used when cutting IDs to > > prevent that. > > > > Stephen > > > Ah! Both good questions I should have been smart enough to ask. Since > my mill is not as stiff as would be ideal I tend to take small Z > increments/360 degrees and work my way down taking at least an extra > pass or two at the max depth as spring passes. > > To extend Stephen's question: where are the humps, exactly at 0, 90, > 180 & 270 or offset some. Are they deep enough to not be backlash anomalies? > > Dave > > > ---------------------------------------------------------------------- > -------- > > Live Security Virtual Conference > > Exclusive live event will cover all the ways today's security and > > threat landscape has changed and how IT managers can respond. > > Discussions will include endpoint security, mobile security and the > > latest in malware threats. > > http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > ---------------------------------------------------------------------- > -------- > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. > Discussions will include endpoint security, mobile security and the > latest in malware threats. > http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ---------------------------------------------------------------------------- -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
