On Friday 04 July 2014 03:08:45 Marcus Bowman did opine And Gene did reply: > On 4 Jul 2014, at 02:28, Jon Elson wrote: > > On 07/03/2014 04:18 PM, Gene Heskett wrote: > >> But it occurs to me that this code is dig cutting, meaning the bit > >> as it dulls, will skid rather than shave at first contact and be > >> pushed farther and farther off the line until it snaps. > > > > I have been climb milling since 1997, when I got ballscrews > > on the > > machine. I almost never conventional mill, as it leads to more > > wear on the cutter, and massively worse surface finish on > > aluminum. > > I certainly agree with that. I typically rough out using conventional > milling and cutters designed specifically for aluminium, then finish > with a climb cut. Increasingly, though, I do the roughing cuts using > climb milling too. Finishing with a climb cut produces a mirror-like > finish that needs no further work. The only fly in the ointment is > backlash, even on ballscrews, where climb milling tends to reveal any > tendency for the nut to 'float' on the screw as the feed changes > direction. If the cutter is long, and its in full contact with the > work (e.g. a 40mm long cutter with 38mm in contact with the work (not > taking a 38mm deep cut all at once, of course) it can leave a mark on > the work. Double ballnuts might solve that. See the photo currently > at > www.cncintheworkshop.com/Welcome.html > for example. > The top of the yoke was flycut, but the sides are 38mm deep and cut > with an end mill. It goes straight to the platers to be gold plated. > > Marcus
Thats beautiful work Marcus, I'm jealous. My toy has never been in the same ballpark with machines that can do that. I always see horizontal lines from what can only be imperfections in the tools sharpness. And vertical lines that I assume come from the lack of another half ton of cast iron in the frame. 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) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ Open source business process management suite built on Java and Eclipse Turn processes into business applications with Bonita BPM Community Edition Quickly connect people, data, and systems into organized workflows Winner of BOSSIE, CODIE, OW2 and Gartner awards http://p.sf.net/sfu/Bonitasoft _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
