On Wednesday 25 September 2019 08:20:38 andy pugh wrote: > Arcs are tangential if their centre points lie on a common line. > So to create an approximate spiral from 90 degree arcs the centres > need to step around a square, offset from the arc centre by 1/8 the > arc lead. > > https://photos.app.goo.gl/x3p5SRsGrM8XQ29G8
Interesting Andy, I was wondering how that might be done. But "arc lead" is a phrase that didn't translate at all well until I saw the cad plot. What I've done tends to leave a mark, particularly if blending has been left enabled, is to go around the circle in steps inward of half the tool diameter, do another smaller radius circle. Wash rinse and repeat till the center has been cut away. The mark, if its important can be removed by going back to the first circle, expanding it by .0002 or so and making 2 more circles to clean it up. Takes a sharp tool, which by the end of the operation isn't unless its running gonad deep in cutting oil. Best if the oil is misted, at high enough pressure to keep the swarf cleared away. And thats something I've not yet setup on the 6040, what mist I can throw is a diluted mix of some pale green water based mix I paid $30 for a gallon of. And I'm not happy with the way it works as it may actually make hot alu weld itself to the tool worse than dry. And I need to get a waterproof spoil board on the bed. Its not even flat. The 6040 is a piece of junk is the bottom line. Much too flexible in the y axis, way to easy to setup a chatter. Curable by a 2% change in spindle speed, sometimes. I'm still learning. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
