On Mon, 2008-07-28 at 11:26 -0500, Jon Elson wrote: > Kirk Wallace wrote: > > On Mon, 2008-07-28 at 00:33 -0500, Jon Elson wrote: > > ... snip > > > >>you might be > >>able to cobble up a substitute by making a disc with a narrow > >>slot and one of those U-shaped optical sensors from a floppy drive. > > > > > > I have thought about this, but I wonder how accurate these are. If you > > want to resolve .0002", I think you typically need angular accuracy > > to .16 degrees. I guess I could try it to find out. > > > I came up with .36 degrees. A good-sized disc with a > narrow-enough slot should work. Basically, you are making a > 1000 line resolution encoder, but with only one line. > > Jon
Oops. I meant half of .36 which is .18, but really, the more I think about it, the important bit is how consistent sensing one edge is. -- Kirk Wallace (California, USA http://www.wallacecompany.com/machine_shop/ Hardinge HNC/EMC CNC lathe, Bridgeport mill conversion, doing XY now, Zubal lathe conversion pending Craftsman AA 109 restoration Shizuoka ST-N/EMC CNC) ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
