I agree BUT everything has limits. 5 axis is not a general panacea. Machine geometry matching the desired result is paramount. A programmer friend always said he could "program" almost anything with a .020in end mill 40 inches long and it would work on the screen.
On Wed, Sep 11, 2024, 10:01 PM Dave Engvall <dengv...@charter.net> wrote: > There is nothing like machine geometry that fits the job you want to do. > :-) > > > On Apr 12, 2024, at 9:08 AM, Stuart Stevenson <stus...@gmail.com> wrote: > > > > Good morning, > > I am sitting here at 70 wondering how people get along without 5 axis. A > > shop here in Wichita sent me 500 parts to run. He was running them on a 4 > > axis mori seiki. The runtime was a little over an hour. He wanted to > clear > > machine time. He furnished programs, material, fixtures, cutters. The > > envelope was 8 inches X 4 inches X 1 inch. We called them porkchops. Flat > > bottom but with standing ribs at angles and contours. Long, small > diameter > > cutters to reach small corners. I programmed the parts for my 5 axis, > made > > new fixtures (a plate with locating bushings) and used much shorter > > cutters. Machine run time was now 18 minutes. You CAN do 5 axis parts on > 3 > > axis and 4 axis machines BUT (it is a very big but) it takes more time > and > > effort. > > > > My maternal grandparents were born in 1894 and 1895, My paternal > > grandparents were born in 1903 and 1904. They also had stories. > > > > regards > > Stuart > > > > > > On Fri, Apr 12, 2024 at 10:33 AM Chris Albertson < > albertson.ch...@gmail.com> > > wrote: > > > >> > >> > >>> All very true and well for someone equipt with the income and mental > >> gear to use that chain of tools profitably. But I'm an old Iowa farm > kid, > >> we made what we needed. The "store" was 15 miles of horse drawn wagon > over > >> a mud road the county graded about 2x a year and all of a days ride in a > >> wagon away. So we grew it, or made it from the woodyard, whatever. 2 > miles > >> to the 1 room school, I rode an old gentle mare the first mile but had > to > >> walk the 2nd mile because there wasn't a barn for the mare during the > day > >> any closer to the school when the weather was bad. Grandpa across the > road > >> had electricity, a 32 volt delco wet glass batteries, charged by a > zenith > >> windcharger. The prop broke, so mother who was the only girl in the 1929 > >> class on aviation technology at Des Moines Tech Hi School, proceeded to > >> teach her father how to carve the wing chord in a new prop. Worked well > in > >> less wind than the one we could get from Chicago. That led to grandpa > >> having the first electric washing machine in Madison County Ia when the > >> Maytag hit & miss tried to start backwards, broke the starter gears and > >> grandma's ankle. A wagon load of shelled corn went to town, and was > >> replaced by an electric motor and enough heavy wire to convert the > Maytag. > >> I still wear scars on one hand from getting it caught in the wringer > when I > >> was 5. We did not want for anything, we "made do" That is a hard habit > to > >> outgrow. > >> > >> But today you own a computer, lots of CNC equipment, a 3D printer and > >> education is free and just a mouse click away. None of the stuff I > wrote > >> about costs even one dollar. I’m the old ririred guy now. Fusion360 > is > >> free to use. I can print ther prats and then if. Needed sand the same > >> design to CNC machine or to an injection molder > >> > >> I think you are right about relativity, Einstein very much admired James > >> Clerk Maxwell. Someone said Einstein ”stood on the shoulders of > Newton”. > >> Einstein corrected him and said “I stood on Maxwell’s shoulders”. > >> > >> Thanks for the story. I always like to hear those “when I was a kid…” > >> stories. My four grandparents were born in 1902 through 1911 they > could > >> talk about the days before radio broadcasting and one-room schoolhouses. > >> One grandfather was a professional boxer in the 1920s and traveled a > lot. > >> But even more interesting to me, my wife’s parents and uncles were born > in > >> pre-war Japan. I think they lived through more change than any living > >> American. Sadly the last of them is in very poor health. My wife is > >> visting her mom in Tokyo right now. > >> > >> Maybe when I am older I will talk about the days of manually driven gas > >> cars. > >>> > >>>> > >>>>> > >>>>> My electronics education is 100% self taught. My mother gave me an IQ > >> good enough to pass the CET test w/o cracking a text to study it. I > >> understand the physics of it including Relativity. Electronics and > >> Relativity go hand in hand, cannot be separated. > >>>>> > >>>>>>>>> On Apr 10, 2024, at 12:09 AM, gene heskett <ghesk...@shentel.net > > > >> wrote: > >>>>>>>>> > >>>>>>>>> On 4/10/24 01:57, John Dammeyer wrote: > >>>>>>>>>> A friend and I have been discussing exactly how to write the > >> G-Code to > >>>>>>>>>> create a spiral scroll. > >>>>>>>>>> His rotary table 90:1 reduction with a 1600 micro-step motor > >> could be set up > >>>>>>>>>> to move N steps for each step of the X axis to create the > >> spiral. But that > >>>>>>>>>> approach seems clumsy. > >>>>>>>>>> Say I wanted to cut a scroll with a 6mm pitch using a 3mm > cutter. > >>>>>>>>>> Without using G2 or G3 it's really just a triangle isn't it? > >> Move rotary > >>>>>>>>>> table distance A and move X axis distance A'. Do it in small > >> enough > >>>>>>>>>> increments and you get a spiral. But I feel like I'm missing > >> something > >>>>>>>>>> really simple. > >>>>>>>> Do you need a rotary table to cut a spiral? It is just a series > >> of locations in (x,y). OK, if you wanted to use only (say) the X and A > >> axis then you should use polar coordinates, not cartesian. The equation > of > >> a spiral on polar coordinates is very simple. Then you evaluate itat > many > >> thousands of points and at each point write gcode to “cut to” that > point. > >> You would not need the rotary table. > >>>>>>>> Also why think in micro-steps and worm gear rates, you are using > >> LCNC to do the kinematics, Use millimeters. > >>>>>>>> I think this problem shows that in some cases you really can not > >> write the gcode by hand. FOr continous curves in (x,y) there might be > >> 100,000 or more lines of code in the file, especially if you don’t do > the > >> cut in one pass. You would nee towrite software to generate the g-code. > >> Or use existing software, a lot of CAD systems will do this for you > >>>>>>>>> First, a 90/1 is quite high. I have two rotary's, both consisting > >> of a 3NM 3phase stepper/servo I made by combining the 3NM motor with a > 5/1 > >> worm. Using a screw in the worms output hub as a single prox sensor > index > >> pulse generator. To calibrate a complete rev, I measure the steps by > >> starting the count on the 3rd turn ans stopping the count on the 103rd > >> turn, which gives me a scale*100. Shift the decimal point 2 places left > >> this becomes the scale for the axis in the .ini file. All this math in > >> linuxcnc is floating point so I can ask it for 33.333 degrees and it > will > >> run to what it thinks is 33.333 degrees. This stepscale: > >>>>>>>>> STEPSCALE = 22.22222222222 = 1 degree > >>>>>>>>> So one count is about 1/22.22222222222 degrees, probably less > than > >> the backlash in the rvs39 worm, a pretty cheap worm. > >>>>>>>>> > >>>>>>>>> Currently to make one of my maple vise screws, starting at 0 > >> degrees its around 60,000 degrees it turns for around 400 mm of screw > that > >> y travels. Then I lift the tool, turn it another 180 degrees, re lower > the > >> tool and bring y back to zero and b=180. Makes a perfect two start > buttress > >> thread. The B is turning, in perfect sync with the Y motion, at > something > >> in the 300 to 400 rpm range. That 3NM motor is heating but not > dangerously > >> so. > >>>>>>>>> > >>>>>>>>> There is no reason you couldn't lay it down to make a C drive, > and > >> simultaneously drive X Z & C to carve an impeller in a quite serviceable > >> scroll. > >>>>>>>>> > >>>>>>>>> The versatility of the closed loop stepper/servo, which does > >> EXACTLY what the TP tells it to do, without a PID in the path, is > amazing. > >> I have them rigged to e-stop linuxcnc in about a millisecond if they > make > >> an error, like losing a step. Tested till the cows come home, has yet to > >> happen working a job. I haven't hobbed any gears, but it certainly seems > >> accurate enough to do it. > >>>>>>>>> > >>>>>>>>>> Suggestions? > >>>>>>>>>> Thanks > >>>>>>>>>> John > >>>>>>>>>> _______________________________________________ > >>>>>>>>>> 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 <mailto: > >> Emc-users@lists.sourceforge.net> <mailto: > Emc-users@lists.sourceforge.net> > >> <mailto: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 <mailto: > >> Emc-users@lists.sourceforge.net> <mailto: > Emc-users@lists.sourceforge.net> > >> <mailto:Emc-users@lists.sourceforge.net> > >>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users > >>>>>> _______________________________________________ > >>>>>> Emc-users mailing list > >>>>>> Emc-users@lists.sourceforge.net <mailto: > >> Emc-users@lists.sourceforge.net> <mailto: > 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 <mailto: > >> 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 > >> > > > > > > -- > > Addressee is the intended audience. > > If you are not the addressee then my consent is not given for you to read > > this email furthermore it is my wish you would close this without saving > or > > reading, and cease and desist from saving or opening my private > > correspondence. > > Thank you for honoring my wish. > > > > _______________________________________________ > > 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 > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
