> From: marcus.bow...@visible.eclipse.co.uk > On 2021-01-02 06:53, John Dammeyer wrote: > > I have noticed the 3D > > printed pulleys are noisier than the metal ones. > > I wonder whether that is because the surface of the teeth will > inevitably be rougher than if they had been die-cast or machined? > > > But the noisy grind > > of the stepper motor is also gone. > > Got to be a bonus. > > > More when it's wired up to LinuxCNC. > > Looking forward to that. Following this topic with interest. > > Marcus
One other thing I've noticed that I believe was there with the stepper (25 ipm max) was the sound when bringing the table downwards. I think for the most part the load of the table was always on the top edge of the leadscrew so never really any backlash issues. But high speed downward travel sounds a bit like the leadscrew may move faster than the table can fall due to gravity. Or at least the friction on the ways limits top speed. Kind of like free falling before pulling the rip cord. Once you reach terminal velocity the resistance of the air counteracts the acceleration of gravity. So even if the ACME screw wasn't there the table would fall of course. But it might well be slower than the 156.25ipm I can achieve with the motor. So the screw would go faster than the table and pull away from the top loaded edge. Once the backlash was made up the leadscrew then pulls down on the knee assembly giving it a bit of a push which then accelerates it to bump against the top edge again. It's not that it's rattling but there's a bit of that between the two bevel gears and the ACME screw. Going up is fast and smooth. John _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
