> > Good thinking. And here I've been extremely impressed with the decel > damping associated with the stopping on target that the stepper/servo's > can do in place of the 2 to 7 microsteps of overshoot a normal stepper > might do getting stopped. But watching the error in plastic on a much > faster 3d printer just prompted me to switch the psu out for one with 2 > amps more surge and 30 volts for nearly a 2x speed boost. The clue was > an 8mm circular hole with a straight line from 6 to 9 oclock when both > motors were moving at the same time. My theory was that it took the > short cut cuz the psu was borderline puny. I'll find out for sure when > the bearings for the Y carriages arrive from tronxy around the end of > next week and I make the final adjustments to square up the belt paths > on that corexy printer. Corexy's have to be dead square in order to > maintain the belt tension as it moves. The advantage is that no motor > is flying weight so it can lay plastic 2-10 times faster.
I really need to purchase or make myself a good 3d printer with linear rails and sturdy enough to print faster and also with better quality. Although I'm not always doing lots of parts I would like to have the option. I mostly print PET-G, Nylon and ABS on a modded Ender 5 Pro, but my speeds are way lower than what a CoreXY or any of those can handle. I'm always thinking about upgrading the Ender 5 to linear rails but maybe building something from scratch is a better option. I'm mostly inclined to the full build because I would like at least a 500 mm x 500 mm surface on the print bed. > Are you grinding for final finish on those cams or just keeping the tool > in the video razor sharp? > I'm retrofitting a semi auto production cylindrical grinder into a fully auto LCNC controlled one. I plan to finish cams and possibly crankshafts too. With the experience on the Mazak doing squares and cams I'm most than confident the grinder will work perfectly. There's a guy from Brazil that did exactly what I'm doing now but instead of using a C axis or external offsets to grind the shape of the lobe, he treated his rotary axis as a linear one and played with the path blending tolerance to get the shape smooth. It worked well but I don't really like that approach too much. I'll be using a Heidenhain 125.000 ppr to capture the spindle position so using eoffsets with that resolution will give me a nice and smooth finish. El sáb, 3 ago 2024 a las 19:48, gene heskett (<ghesk...@shentel.net>) escribió: > On 8/3/24 12:23, Leonardo Marsaglia wrote: > >> > >> As a roughing cut thats pretty decent. Can your X move like that while > >> loaded with the grinders weight? My grinder is a 1/4 shank and several > >> lbs. With an 8mm x screw, that much weight would be pushing that screw > >> pretty hard. > >> > > > > I didn't weigh the entire X chariot so I'm dimensioning it just based on > > other machines of similar size. I'm using a 40 mm ballscrew (ground or > > rolled that's yet to be determined) with 5 mm of lead. That will be > > commanded using a 3.8 KW servo motor which can output 15 NM of nominal > > torque. Since this is a grinder and the part is going to spin slower > than a > > turning operation I really don't mind a lot about max speed on the X axis > > but more about max acceleration. > Good thinking. And here I've been extremely impressed with the decel > damping associated with the stopping on target that the stepper/servo's > can do in place of the 2 to 7 microsteps of overshoot a normal stepper > might do getting stopped. But watching the error in plastic on a much > faster 3d printer just prompted me to switch the psu out for one with 2 > amps more surge and 30 volts for nearly a 2x speed boost. The clue was > an 8mm circular hole with a straight line from 6 to 9 oclock when both > motors were moving at the same time. My theory was that it took the > short cut cuz the psu was borderline puny. I'll find out for sure when > the bearings for the Y carriages arrive from tronxy around the end of > next week and I make the final adjustments to square up the belt paths > on that corexy printer. Corexy's have to be dead square in order to > maintain the belt tension as it moves. The advantage is that no motor > is flying weight so it can lay plastic 2-10 times faster. > > Are you grinding for final finish on those cams or just keeping the tool > in the video razor sharp? > > > > El vie, 2 ago 2024 a las 14:37, gene heskett (<ghesk...@shentel.net>) > > escribió: > > > >> On 8/2/24 12:23, Leonardo Marsaglia wrote: > >>> Hello Gene, I hope you're doing well! > >>> > >>> Here is a little footage of the fastest I've moved the X axis on the > >> mazak: > >>> https://youtube.com/shorts/fx6Elmy2GB4?si=oYQ7x1yheyhZOh5- > >> > >> As a roughing cut thats pretty decent. Can your X move like that while > >> loaded with the grinders weight? My grinder is a 1/4 shank and several > >> lbs. With an 8mm x screw, that much weight would be pushing that screw > >> pretty hard. > >> > >> > >> > >> > >> > >>> > >>> Being almost a square and considering the circunscribed diameter is > about > >>> 37 mm is pretty good. For the X axis I have a max speed of 500.0 mm/sec > >> and > >>> 10000.0 mm/sec^2 of max acceleration. I kind of have to correct the > jerk > >>> for this axis because for some shapes I can notice it's a little too > >> much. > >>> But for the most part I'm ok with the way it works. > >> > >> Yes, makes it look easy. > >> > >>>> I have done that, but the spindle speed is suprisingly slow if X is > >> slow. > >>>> > >>> > >>> Well, I'm designing this machine to have a slight better response than > >> the > >>> Mazak, but also being a grinding machine I don't really need that much > >> RPMs > >>> on the part spindle so for the majority of parts we make it will be ok. > >>> I'll be posting videos as soon as the machine is ready! > >> > >> I might add that my Sheldon is the first machine I put the > >> stepper/servo's on. They doubled the speeds. > >>> > >>> > >>> > >>> El vie, 2 ago 2024 a las 12:55, gene heskett (<ghesk...@shentel.net>) > >>> escribió: > >>> > >>>> On 8/2/24 10:52, gene heskett wrote: > >>>>> On 8/2/24 05:45, Leonardo Marsaglia wrote: > >>>>>>> > >>>>>>> So this would also work for a mill that has an AC Servo running > >>>>>>> step/dir. > >>>>>>> Once the motor is connected to the spindle with a toothed belt > >>>>>>> rather than > >>>>>>> V belt. > >>>>> > >>>>> I must be missing some context here. I have been feeding back for > >>>>> spindle speed control, an encoder generated ABX set of quadrature > >>>>> signals generated by ats-667's which are watching the spindle > backgear > >>>>> teeth go by, for about a decade. What has the presence or absence > of a > >>>>> v-belt in the path got to do with it?. > >>>>>>> Cool! > >>>>>>> > >>>>>> > >>>>>> I have the same doubt about the kind of belt I should use. In > theory, > >>>>>> several V belts well tensioned should work perfectly without > slipping > >>>> and > >>>>>> the encoder on the spindle (this one of course coupled with a timing > >>>>>> belt) > >>>>>> should be able to keep up with the position and nothing should go > >> wrong. > >>>>>> The lathes we have all work this way and I have never experienced > belt > >>>>>> slipping. But for some reason I feel more confident using timing > belts > >>>>>> all > >>>>>> the way. I don't know if this is an overkill and I should go with > the > >>>>>> simpler V belts. Remember that this machine is going to be grinding > >> cams > >>>>>> and eccentrics. > >>>>>> > >>>> I have done that, but the spindle speed is suprisingly slow if X is > >> slow. > >>>> > >>>>>> El vie, 2 ago 2024 a las 6:33, Leonardo Marsaglia > >>>>>> (<ldmarsag...@gmail.com>) > >>>>>> escribió: > >>>>>> > >>>>>>> Thanks Andy for the link! Now it's time to play a little bit with > the > >>>>>>> config and make it work :) > >>>>>>> > >>>>>>> El dom, 28 jul 2024 a las 6:21, andy pugh (<bodge...@gmail.com>) > >>>>>>> escribió: > >>>>>>> > >>>>>>>> On Sat, 27 Jul 2024 at 18:41, Leonardo Marsaglia > >>>>>>>> <ldmarsag...@gmail.com> > >>>>>>>> wrote: > >>>>>>>> > >>>>>>>>> For this, I think I read there's a caxis.comp module that If I'm > >> not > >>>>>>>>> mistaken Andy wrote. > >>>>>>>>> > >>>>>>>>> Is there a place to get that file? Because I couldn't find it > yet. > >>>>>>>> > >>>>>>>> > >>>>>>>> > >>>> > >> > https://forum.linuxcnc.org/10-advanced-configuration/42171-spindle-step-dir-servo-ramp-down-before-stop-on-m-stop-command?start=120#209694 > >>>>>>>> > >>>>>>>> > >>>>>>>> -- > >>>>>>>> atp > >>>>>>>> "A motorcycle is a bicycle with a pandemonium attachment and is > >>>>>>>> designed for the especial use of mechanical geniuses, daredevils > and > >>>>>>>> lunatics." > >>>>>>>> — George Fitch, Atlanta Constitution Newspaper, 1912 > >>>>>>>> > >>>>>>>> > >>>>>>>> _______________________________________________ > >>>>>>>> Emc-users mailing list > >>>>>>>> Emc-users@lists.sourceforge.net > >>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users > >>>>>>>> > >>>>>>> > >>>>>> > >>>>>> _______________________________________________ > >>>>>> Emc-users mailing list > >>>>>> Emc-users@lists.sourceforge.net > >>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users > >>>>> > >>>>> Cheers, Gene Heskett, CET. > >>>> > >>>> Cheers, Gene Heskett, CET. > >>>> -- > >>>> "There are four boxes to be used in defense of liberty: > >>>> soap, ballot, jury, and ammo. Please use in that order." > >>>> -Ed Howdershelt (Author, 1940) > >>>> If we desire respect for the law, we must first make the law > >> respectable. > >>>> - Louis D. Brandeis > >>>> > >>>> > >>>> > >>>> _______________________________________________ > >>>> Emc-users mailing list > >>>> Emc-users@lists.sourceforge.net > >>>> https://lists.sourceforge.net/lists/listinfo/emc-users > >>>> > >>> > >>> _______________________________________________ > >>> Emc-users mailing list > >>> Emc-users@lists.sourceforge.net > >>> https://lists.sourceforge.net/lists/listinfo/emc-users > >> > >> Cheers, Gene Heskett, CET. > >> -- > >> "There are four boxes to be used in defense of liberty: > >> soap, ballot, jury, and ammo. Please use in that order." > >> -Ed Howdershelt (Author, 1940) > >> If we desire respect for the law, we must first make the law > respectable. > >> - Louis D. Brandeis > >> > >> > >> > >> _______________________________________________ > >> Emc-users mailing list > >> Emc-users@lists.sourceforge.net > >> https://lists.sourceforge.net/lists/listinfo/emc-users > >> > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > Cheers, Gene Heskett, CET. > -- > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author, 1940) > If we desire respect for the law, we must first make the law respectable. > - Louis D. Brandeis > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
