Remember the workflow. You start with a 3D model where the resolution is literally "perfect" as the curves are defined by mathematical functions. Then you convert the 3D model to an STL and an STL can contain only straight lines. No circles, no curves. When you make the STL you get to specify a maximum error but small errors mean big files.
So when you look for a gear or sprocket ALWAYS look to see if you can get the 3D CAD file and not just the STL. The best places are the big resellers like Boston Gear, McMaster Carr, SPD,.. they all have "perfect" 3D CAD models, usually.STEP file type. If you do download an STL then you are accepting some other random person's idea of what is a good error tolerance without even knowing what he specified. *So make the STL file yourself. * I usually go overboard with resolution in the STL and specify something like 0.001 mm or less allowed error. The next step is manufacturing where you get to specify how it is sliced and printed or how the file is cut on a mill. On Tue, Nov 10, 2020 at 9:15 PM Gene Heskett <ghesk...@shentel.net> wrote: > Greetings 3d printer X-spurts; > > I just downloaded the .stl kit for a nema 17 powered, gt2 belt driven > reduction gear. I thought I see how it rendered since I had such poor > luck with that previous harmonic drive. so I update cura to 4.8.0, > loaded up the teeny little gt2 belt sprocket that fits the motor shaft. > > I noted that cura was lifting the head and moving it off about 2cm to > about half a cm above, I assume to give that small a part a chance to > cool between layers. But it still finished in about the 15 minutes it > said it will take when cura sliced it. And the print is easily 5x > sharper, a quite usable gt2 rendering where before, an xl pulley was > just barely usable with a belt tight enough to satisfy Jack Benny! > > So I've come to the conclusion that quite a bit of what you can download > as .stl's, are intended to be very low resolution so as not to compete > with the same you-toobers commercial offerings. And my printer isn't > the piece of crap I turned off in disgust 6 weeks back. I am impressed. > > 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 > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
