On Sunday 02 August 2020 13:32:03 Bruce Layne wrote: > I'd 3D print some low profile clips for the glass plate, or (my > preference) use high temperature double sided adhesive to secure the > glass plate to the print bed. I initially thought I'd be swapping > glass beds between prints, but in practice, I prefer having the glass > bed fixed to the printer. KISS. I'd need to wait for the glass bed > to heat so I wouldn't save much time by avoiding the cool down phase, > and handling a hot glass plate and swapping glass beds in general > sounds goofy to me. I'd eliminate the clothes pins or binder clips > ASAP. It's much better to have nothing sticking up where the nozzle > can crash into it. > > My 3D printers were fine with no retuning after I added some thick > borosilicate glass, but my printers only move the bed vertically in > .2mm steps when printing. The X and Y stages are suspended above, > running on linear guide rods. If you were concerned about altered > acceleration on your Ender 3 clone, I'd try printing two small test > cubes, separated by 100mm in the Y direction, at 10% higher speed than > you'd usually use. If the acceleration was too much for the stepper > motors or the print quality was adversely impacted by the momentum of > the added mass, only then would I try to reduce the acceleration. I'm > too old to fix problems that don't exist or otherwise looking for > dragons to slay.
True here too, but I've never had dragon for dinner Bruce, it might be good eating. ;-) > In practice, there is a high gear ratio so the 3D printer doesn't need > much torque, and most of the torque requirements are when the motors > are at low RPM where stepper motors have their most torque. I think > these glass bed upgrades are usually done without changing the motor > parameters. > > On 8/2/20 10:59 AM, Gene Heskett wrote: > > Greetings all; > > > > Several question mark below. > > > > Those glass plates for my ender-3 Pro's build plate use have > > arrived, and I'm somewhat taken aback by the mass of a 230x230mm by > > 4mm piece of glass. This at least doubles, likely more, the weight > > the y motor has to manhandle, in my mind affecting the ballistics of > > its movement. No glass clips or instructions came with it although > > the glass was packed to survive a tactical nuke, So I'll raid the > > laundry room for some spring clothes pins. Plastic, lighter than the > > old wooden ones, but I stuck a couple on the front of the bed and > > the heat isn't bothering them. > > > > The stock Merlin driver has some adjustments for both acceleration > > and jerk. Accel is currently set at 500, sounds pretty instant to me > > and jerk is set at 8 but thats a new term for me and I have no idea > > of how a change to that effects the machine. > > > > Given the increased mass to move, is it even possible to keep the > > working velocities at the currently set values, or is there a way to > > determine what is optimum for this added mass it has to move? > > > > I'm assuming changes in the ballistics would have to be set in the x > > axis at the same time to keep it from bending corners. > > > > Or, would I be better off spending the sheckles for one of the > > improved 32 bit driver boards I see being offered? Power supply > > might come into play too as its only 24 volts now, which will effect > > its accel and ballistics envelope too. > > > > Discussion, educational/reference URL's all welcome. > > > > Thanks all. > > > > Cheers, Gene Heskett > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users 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) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
