On 23 March 2017 at 01:23, hubert <h...@hbahr.org> wrote: > How are you approaching this project? I am assuming that you > are starting with a plate that will be attached to the 4th axis and > machining that plate to accept the cam lock studs and cam locks. In my > case I can get a complete set(6 ea) of locks from my Lathe source for US > $36. Are there any precautions that I should watch for when I attempt > this project?
The basis of the project is a harmonic drive with integral motor and through-shaft. I have an FHA-25 size, but FHA-32 might be better. The current model drives (FHA-25C) seem to have a serially interfaced encoder, which looks complicated. The FHA-25B is a model that HD have no data on, but I found a document from ESO http://www.ls.eso.org/lasilla/support/electronics/Documentation/PDF/3P6-DSD-ESO-60400-0001.pdf Which gives the pinout and wire colours (if you look carefully) and that is a simple quadrature encoder + hall sensor setup and so rather easier to drive. eBay has a few of these drives, at widely differing prices, some with the dedicated servo amp. http://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=FHA-25B&LH_PrefLoc=2&_sop=15 Mine is a FHA-25B-3015-E150C-SP I am making a pattern to make a cast-iron housing for bolting to my mill table, designed around a max swing of 250mm. Making extra castings is trivial at that point. The output face of the drive has a circle of 8 x M6 holes on a 74mm PCD. This is actually slightly awkward for a D1-4 spindle nose, which has 3 pins and tangential retainers. I could only get 3 bolts in if I kept the standard tangential retainers, so I am using axial retainers. D1-5 already has axial retainers, but also has 6 studs. I have modelled the D1-5 nose and attempted to fit the 74mm PCD holes in. It's not pretty. two of the holes are impossible, I think, and the others need to be counterbored so deep that the heads are lower than the D1 cams (or they have to go through them). And they eat into the retaining taper. http://a360.co/2nMOEnm should let you view the 3D-model of the D1-4. I think that the answer would be to make the dummy-spindle-nose in two parts, one that bolts to the harmonic drive, and then a second section that bolts to that which has the taper. (then in-situ grind the locating taper, ideally). -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1916 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
