On 16 Jul 2017, at 06:37, andy pugh wrote: > On 16 July 2017 at 02:46, Gene Heskett <[email protected]> wrote: > >> Which will do the least damage to a pre-finished part, such as the fairly >> high polished SS barrel? Brass or copper? >
On a three-fingered steady, a different approach is to add rotating bearings to the ends of the fingers. I made a set which use thin ball bearings designed for the bottom bracket on a bicycle. The fingers are forked at the end, with the bearing running on a short hardened shaft. The bearing turns rather than rubs. I would recommend an arrangement which allows the bearing to turn slightly, to align itself with the surface of the shaft. My fingers are square-section because the original design of the steady has flat surfaces against which the fingers slide. Circular-section fingers would be better, to allow the fingers to turn to align the outer track of the bearings to align against the work. Second thought: I may have misunderstood about fingers rubbing on threads; but can you make a female threaded sleeve for your threads? That would give you a circular sacrificial surface for the fingers to rub against. Marcus > Copper is quite sticky, you want brass or bronze. > > > -- > 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 > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
