In other words, you pretend to cut a left-hand thread but have the machine run in reverse so it turns out right hand? Peter Blodow
Am 08.02.2016 11:42, schrieb Marcus Bowman: > On 8 Feb 2016, at 10:04, andy pugh wrote: > >> On 7 February 2016 at 23:37, Marcus Bowman >> <marcus.bow...@visible.eclipse.co.uk> wrote: >> >>> Easy. mount the tool upside down, and start at the blind bottom. >> Sorry, I am not quite understanding your description? >> > Yes; apologies; my rather quick response was a bit cryptic... > > For an internal right-hand thread, the problem is often that the tool feeds > into the hole from the right, and bumps into the bottom of the hole. It would > be the same for an external thread bumping into a shoulder on the left. > Machine the hole to the ID for the minor diameter of the internal thread, > then create a clearance groove of 1 pitch width, and just deeper than the > thread height, at the bottom of the hole. That blind bottom still a problem > if your reactions are as slow as mine, so, unless you have auto-disengagement > for the leadscrew, avoid the problem by cutting the thread from left to > right, starting with the tool in the clearance groove, applying a cut, and > feeding outwards into fresh air. > Run the spindle in reverse. > The tool can either be mounted against the front wall, upright; or can be > mounted against the rear wall, but inverted. > (I think I have those the right way around...) > I've used this method on both internal and external threads, with front and > rear toolposts and with the tools the right way up or upside down, to suit > the directions of cut,and it works a treat. The key is to cut away from the > blind end or the shoulder (and to take care with spindle direction and tool > orientation, both of which can cause local overheating of the brain's > visualisation processing area). > All much easier with CNC I dare say... > > Marcus > >> -- >> atp >> If you can't fix it, you don't own it. >> http://www.ifixit.com/Manifesto >> >> ------------------------------------------------------------------------------ >> Site24x7 APM Insight: Get Deep Visibility into Application Performance >> APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month >> Monitor end-to-end web transactions and take corrective actions now >> Troubleshoot faster and improve end-user experience. Signup Now! >> http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ > Site24x7 APM Insight: Get Deep Visibility into Application Performance > APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month > Monitor end-to-end web transactions and take corrective actions now > Troubleshoot faster and improve end-user experience. Signup Now! > http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > --- Diese E-Mail wurde von Avast Antivirus-Software auf Viren geprüft. http://www.avast.com ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
