I have looked at some gearing diagrams of gear hobbers and I noticed that a 'differential' gear set was included. What does that actually do? I suspect it is for cutting prime number gears?
----- Original Message ----- From: emc-users-requ...@lists.sourceforge.net To: emc-users@lists.sourceforge.net Sent: Sunday, October 2, 2016 12:22:56 AM Subject: Emc-users Digest, Vol 126, Issue 2 Send Emc-users mailing list submissions to emc-users@lists.sourceforge.net To subscribe or unsubscribe via the World Wide Web, visit https://lists.sourceforge.net/lists/listinfo/emc-users or, via email, send a message with subject or body 'help' to emc-users-requ...@lists.sourceforge.net You can reach the person managing the list at emc-users-ow...@lists.sourceforge.net When replying, please edit your Subject line so it is more specific than "Re: Contents of Emc-users digest..." Today's Topics: 1. Re: Estimated time remaining (Danny Miller) 2. Re: CNC little hobber (andy pugh) 3. Re: Estimated time remaining (sam sokolik) 4. Re: Estimated time remaining (Todd Zuercher) 5. Re: CNC little hobber (Dave Caroline) 6. Re: CNC little hobber (Gregg Eshelman) ---------------------------------------------------------------------- Message: 1 Date: Sat, 1 Oct 2016 17:27:25 -0500 From: Danny Miller <dan...@austin.rr.com> Subject: Re: [Emc-users] Estimated time remaining To: emc-users@lists.sourceforge.net Message-ID: <1692ab96-d54e-b4b1-4825-5d81dcb18...@austin.rr.com> Content-Type: text/plain; charset=windows-1252; format=flowed The estimator DOES just use distance & feedrate, not acceleration. This is effective for estimating 2D cuts but junk for 3D carving, which hinges primarily on acceleration. There is no one effective "factor". I have 3D carvings which took 4x longer than estimated, others 6x. If it is only a gentle slope then the factor could be 1x, all for the same profile. When tuning a machine, you can reduce the axis max velocity in order to increase the max acceleration, and this can in fact make the machine run faster. Note an arbitrary multiplier factor would be useless for tuning, as you need to know the actual effect of the parameter changes. But the feature I proposed- an ETA timer- I don't see how to do it, because the required info isn't on the interface that I can find. Specifically "total line count from the G-code" and "current line number in the G-code". The concept would fail for sure on G-code bearing subroutines but that's not a feature of any of the 3d carving I'm doing. The ETA-by-line-count would be inaccurate on 2D cutting, even without subroutines, because there's no telling how long a vector is. A curved cut can be 10 or 1000 lines but only take a second or two, while a single straight line can be a long cutting time. Danny On 10/1/2016 8:39 AM, Todd Zuercher wrote: > I suppose you might be able to make something like that. > > But I think I have a good idea for improving the run time estimator. Right > now how does it work, does it just use the feed rates X distance to be > traveled? What if it took that and added to it a factor(derived from the > machines acceleration rate) X the number of lines in the file. > > ----- Original Message ----- > From: dan...@austin.rr.com > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Sent: Friday, September 30, 2016 11:30:51 PM > Subject: [Emc-users] Estimated time remaining > > I am doing 3D carving, where the Properties analysis is regrettably useless > for coming up with time estimates due to not taking into account the > acceleration aspect of trajectory planning. > > I did install the cycle timer pvcp and it does certainly help. > > But one thing I noticed- these carvings are "mostly" consistent in how much > time they're taking per-line. It would be accurate enough to be helpful to > calculate: > > Time Remaining=(total # of gcode lines/gcode lines done so far)*cycletime so > far > > Is there any way to do that? All I can see is access to "time". > > Danny > > ------------------------------------------------------------------------------ > > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ > > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------ Message: 2 Date: Sat, 1 Oct 2016 23:36:46 +0100 From: andy pugh <bodge...@gmail.com> Subject: Re: [Emc-users] CNC little hobber To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> Message-ID: <CAN1+YZXeuK7xZAMEh=3g5bax2muuhg+ih1dx1odm6pfo4r2...@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 On 1 October 2016 at 22:49, <richsh...@comcast.net> wrote: > OK, I know nothing about gear hobbing, but have seen that youtube video of > the little hobber, what kind of work would need to be done to build a cnc > version of such a machine? It's actually almost trivial with HAL. https://www.youtube.com/watch?v=ZhICrb0Tbn4 -- 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, 1916 ------------------------------ Message: 3 Date: Sat, 1 Oct 2016 17:45:45 -0500 From: sam sokolik <sa...@empirescreen.com> Subject: Re: [Emc-users] Estimated time remaining To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> Message-ID: <ca6b8c5b-828f-a24b-f6a7-8b82adcf1...@empirescreen.com> Content-Type: text/plain; charset=windows-1252; format=flowed I was wondering if you could create an accurate estimate by creating a sim config with (now just thinking out loud) 1000 times the velocity/accelleraton and the feedrate override set to 1000%. You would run the program in sim - then multiply the time by 1000. (or whatever) I have not thought this through - and it might not be that simple... :) sam On 10/1/2016 5:27 PM, Danny Miller wrote: > The estimator DOES just use distance & feedrate, not acceleration. This > is effective for estimating 2D cuts but junk for 3D carving, which > hinges primarily on acceleration. > > There is no one effective "factor". I have 3D carvings which took 4x > longer than estimated, others 6x. If it is only a gentle slope then the > factor could be 1x, all for the same profile. > > When tuning a machine, you can reduce the axis max velocity in order to > increase the max acceleration, and this can in fact make the machine run > faster. Note an arbitrary multiplier factor would be useless for > tuning, as you need to know the actual effect of the parameter changes. > > But the feature I proposed- an ETA timer- I don't see how to do it, > because the required info isn't on the interface that I can find. > Specifically "total line count from the G-code" and "current line number > in the G-code". The concept would fail for sure on G-code bearing > subroutines but that's not a feature of any of the 3d carving I'm doing. > > The ETA-by-line-count would be inaccurate on 2D cutting, even without > subroutines, because there's no telling how long a vector is. A curved > cut can be 10 or 1000 lines but only take a second or two, while a > single straight line can be a long cutting time. > > Danny > > On 10/1/2016 8:39 AM, Todd Zuercher wrote: >> I suppose you might be able to make something like that. >> >> But I think I have a good idea for improving the run time estimator. Right >> now how does it work, does it just use the feed rates X distance to be >> traveled? What if it took that and added to it a factor(derived from the >> machines acceleration rate) X the number of lines in the file. >> >> ----- Original Message ----- >> From: dan...@austin.rr.com >> To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> >> Sent: Friday, September 30, 2016 11:30:51 PM >> Subject: [Emc-users] Estimated time remaining >> >> I am doing 3D carving, where the Properties analysis is regrettably useless >> for coming up with time estimates due to not taking into account the >> acceleration aspect of trajectory planning. >> >> I did install the cycle timer pvcp and it does certainly help. >> >> But one thing I noticed- these carvings are "mostly" consistent in how much >> time they're taking per-line. It would be accurate enough to be helpful to >> calculate: >> >> Time Remaining=(total # of gcode lines/gcode lines done so far)*cycletime so >> far >> >> Is there any way to do that? All I can see is access to "time". >> >> Danny >> >> ------------------------------------------------------------------------------ >> >> Check out the vibrant tech community on one of the world's most >> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> >> ------------------------------------------------------------------------------ >> >> Check out the vibrant tech community on one of the world's most >> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > > ------------------------------------------------------------------------------ > > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------ Message: 4 Date: Sat, 1 Oct 2016 21:44:58 -0400 (EDT) From: "Todd Zuercher" <zuerc...@embarqmail.com> Subject: Re: [Emc-users] Estimated time remaining To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> Message-ID: <1724068088.78704967.1475372698840.javamail.r...@embarqmail.com> Content-Type: text/plain; charset=utf-8 The current line number is supposed to be available on the pin "motion.program-line" (not sure how well it always works). There has to be a way to glean the total number of lines, but I don't know it. ----- Original Message ----- From: "Danny Miller" <dan...@austin.rr.com> To: emc-users@lists.sourceforge.net Sent: Saturday, October 1, 2016 6:27:25 PM Subject: Re: [Emc-users] Estimated time remaining The estimator DOES just use distance & feedrate, not acceleration. This is effective for estimating 2D cuts but junk for 3D carving, which hinges primarily on acceleration. There is no one effective "factor". I have 3D carvings which took 4x longer than estimated, others 6x. If it is only a gentle slope then the factor could be 1x, all for the same profile. When tuning a machine, you can reduce the axis max velocity in order to increase the max acceleration, and this can in fact make the machine run faster. Note an arbitrary multiplier factor would be useless for tuning, as you need to know the actual effect of the parameter changes. But the feature I proposed- an ETA timer- I don't see how to do it, because the required info isn't on the interface that I can find. Specifically "total line count from the G-code" and "current line number in the G-code". The concept would fail for sure on G-code bearing subroutines but that's not a feature of any of the 3d carving I'm doing. The ETA-by-line-count would be inaccurate on 2D cutting, even without subroutines, because there's no telling how long a vector is. A curved cut can be 10 or 1000 lines but only take a second or two, while a single straight line can be a long cutting time. Danny On 10/1/2016 8:39 AM, Todd Zuercher wrote: > I suppose you might be able to make something like that. > > But I think I have a good idea for improving the run time estimator. Right > now how does it work, does it just use the feed rates X distance to be > traveled? What if it took that and added to it a factor(derived from the > machines acceleration rate) X the number of lines in the file. > > ----- Original Message ----- > From: dan...@austin.rr.com > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Sent: Friday, September 30, 2016 11:30:51 PM > Subject: [Emc-users] Estimated time remaining > > I am doing 3D carving, where the Properties analysis is regrettably useless > for coming up with time estimates due to not taking into account the > acceleration aspect of trajectory planning. > > I did install the cycle timer pvcp and it does certainly help. > > But one thing I noticed- these carvings are "mostly" consistent in how much > time they're taking per-line. It would be accurate enough to be helpful to > calculate: > > Time Remaining=(total # of gcode lines/gcode lines done so far)*cycletime so > far > > Is there any way to do that? All I can see is access to "time". > > Danny > > ------------------------------------------------------------------------------ > > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ > > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------ Message: 5 Date: Sun, 2 Oct 2016 08:02:20 +0100 From: Dave Caroline <dave.thearchiv...@gmail.com> Subject: Re: [Emc-users] CNC little hobber To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> Message-ID: <calfygtmv1jyc-pysvrkzxtwoyvoe5oeem0fntsvezsd4gza...@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 And I used Andy's info and cnc'd a Barber Colman hobbing machine http://www.collection.archivist.info/searchv13.php?searchstr=barber+colman+pd Dave Caroline ------------------------------ Message: 6 Date: Sun, 2 Oct 2016 07:22:42 +0000 (UTC) From: Gregg Eshelman <g_ala...@yahoo.com> Subject: Re: [Emc-users] CNC little hobber To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> Message-ID: <1694714455.4044673.1475392962...@mail.yahoo.com> Content-Type: text/plain; charset=UTF-8 Replacing all the gearing that interconnects the various axes with encoders and motors on each bit that spins. From: "richsh...@comcast.net" <richsh...@comcast.net> To: emc-users@lists.sourceforge.net Sent: Saturday, October 1, 2016 3:49 PM Subject: [Emc-users] CNC little hobber OK, I know nothing about gear hobbing, but have seen that youtube video of the little hobber, what kind of work would need to be done to build a cnc version of such a machine? ------------------------------ ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot ------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users End of Emc-users Digest, Vol 126, Issue 2 ***************************************** ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
