On 5/15/2015 3:28 AM, andy pugh wrote: > On 15 May 2015 at 03:03, Gene Heskett <ghesk...@wdtv.com> wrote: >> I had a session day before yesterday of the back gear countershaft >> squawling pretty bad, so I called Chris at LMS and bought the whole >> headstock for a $132 bill with USPS shipping, and which arrived today. > > https://littlemachineshop.com/products/product_view.php?ProductID=2299&category=1023914534 > ? > > I hadn't realised that the 7x lathes had a back-gear. My 9x (which > seems to be a stretched 7x) had an all-belt arrangement (using the > tiniest of V-belts) > http://www.micro-machine-shop.com/9x20_lathe_belts_1.jpg
The 9x lathes are copies of the Emco Compact 8, with an extra 1/2" of metal on the bottom of the head and tail stocks. The gears in the 7x aren't actually a "back gear", it's a two speed shift that either reduces or increases spindle speed from the input shaft speed. There's no 1:1 drive. For the vast majority of what most people do on a 7x it's best to leave it in low speed. What's surprising is that in all the time various companies have been making copies of the Compact 8, not one of the design's deficiencies has been corrected by any of them. They all use that weedy little belt, no tumble reverse. Nobody has made a gear drive headstock. They all use the same flexible 2 bolt mounting ring for the compound. No manufacturer has designed a proper 2 lever gearbox so change gears aren't needed at all. If they did, such a gearbox would be cannibalized for many old lathes that didn't originally have one. The 9x lathe could be a quite nice hobby lathe IF some company would apply all the common upgrades and fixes various owners have developed for them, and expand the gearbox, and upsize the 7x headstock design to three speeds with 1:1 in the middle. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ------------------------------------------------------------------------------ One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
