On Monday 27 March 2017 03:56:53 Gene Heskett wrote: > On Monday 27 March 2017 00:17:19 Erik Christiansen wrote: > > On 26.03.17 18:53, Gene Heskett wrote: > > > But is 7 the correct factor? It should be fairly easy to jack it > > > back out. > > > > Gene, I've never made one of them, but looking here: > > > > http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&ve > >d= > > 0ahUKEwiE6q-q5PXSAhWGKWMKHeZIAf0QFgg-MAc&url=http%3A%2F%2Funiversalb > >ear > > ings.com.au%2Fdownload-subproducts%2Ftaperlock-bushes&usg=AFQjCNGOFI > >vAU jPQ1JccxaHkdEjC0hT5oA > > > > the first bush in the table seems to be: > > > > atan((35.2 - 33.7)/11.1) = 7.7° included, near as dammit. > So I did the taper turn at TAN[7.7]*total z len which was 0.735"
Finished (except for jacking holes) hub looks great. Set it aside for now. Chuck pulley and hammer around for concentricity etc, spins good and true. Edit code to do the tapered bore, but change for a full inch of Z motion, so I used the TAN[7.7] raw as the inner factor to sub from the bore at z left end. Using one of those cheap $20 a kit of cemented carbide boring bars. Re-shapened with a diamond disk in a dremel. Get it bored big enough (and bore looks like shit, tool is skipping) to start checking fit using the hub I just made at what was supposed to be the same angle. Bored angle too steep by quite a bit. Hub goes in about half way, jams on tip of hub and can be rocked around. Its not trashed yet, but this is where I start fiddling with bar sharpening angles, widening the hole at the deep end until it fits. And changing the bar to a monster I made years ago, a 5/8" diameter bar about 10" long I had made a groove in the side of to hold a small bar that seriously needed some stiffening. Takes std diamond pattern chips. Then gradually reduce the x decrement until it fits. I don't believe the spindle head on this lathe has ever aligned with the z motion of the carriage. I replaced the whole head a year ago after refitting a new head with all metal gears, and while I cleaned the paint overspray off the mating surfaces on its bottom, I think this one is sitting even more out of alignment. At one time years ago I had wasted a piece of cold roll and a few days adding an offset per inch factor to x until it was turning a decent cylinder, and should have painted it on the monitor, as its in the area of 7 thou per inch, but that was on the OEM head assembly. Cheap, mumble mumble, Chinese crap. Andway, change the bar to the big boy, then start shaving the angle is todays project. After I go to the store and get stuff for breakfast and fix it for us. > Cheers, Gene Heskett 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> ------------------------------------------------------------------------------ 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
