On Tue, 15 Feb 2011 16:12:55 -0800, you wrote: >On Tue, 2011-02-15 at 19:55 +0100, Klemen Ozebek wrote: >> Dear all, >> >> on the link below you can se my first test of scratch built lathe which runs >> by EMC2. Hardware which is used on lathe: CT Unimotor AC servo motors, >> Digitax ST AC Drives, Commander SK - for spindle, Mesa 5i20 fpga + 7i33 >> analog servo card + 7i42. >> >> Best regards. > >I am really surprised that your threading can be done at such a high >spindle speed. The axes must have a high acceleration limit. I have to >have a lead in (air threads) of two to four threads to give my Z enough >time to settle to the target feedrate. (Although I think the latest EMC2 >improves this problem.)
Looks right for a servo machine to me :) Here between 600 and 1200 rpm is the norm using steppers, depends entirely on the pitch and the material. I can thread faster than that, it means changing pulleys though which is a PITA, and as all the guards are off the lathe it fires swarf all over the shop at high speeds <G>. My cam program knows the max pulley speeds and max feed and acceleration rates for each axis of the machine. It has material tables too, so tries to give me the optimum for job in hand. 25 passes seems high though for that pitch? In 86xx steel I do 5 passes for 1mm pitch, 10 for 1.5 and 15 for 2mm (all plus 2 spring passes). If I let CAM calculate the passes on removal rate for insert it's much less, it will try and do a 2mm pitch in 7 passes. I can do that but need the coolant on, back to the no covers or guards problem. One thing I definitely don't do is use threading inserts for roughing/finishing cuts before threading - far too expensive for that :) Steve Blackmore -- ------------------------------------------------------------------------------ The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
