I am looking to learn how to create & use worm gears using the BOSL2 gears.scad library (https://github.com/BelfrySCAD/BOSL2). I have used several of the other components in the gears library in the past (specifically the spur_gear & rack), although that was my first time using the library, so I can't say I was necessarily doing it in the most efficient or intended way. Does anybody know of any good tutorials or videos on using the worm gear components? In my model I can use the worm with a rack or with an inverted worm (like a screw, I'm not sure what the proper term for an "inverted worm" is). Even though it took me a little while to learn the rack & spur_gear, that was also my first time using BOSL2 (or any other gear library), so I think I'll be able to learn the worm a little quicker. Any suggestions for a good tutorial or video? Thanks! Nathan Sokalski njsokalski@hotmail.com<mailto:njsokalski@hotmail.com>

Be warned that at the moment, worm gears in BOSL2 don't always work correctly. I'm not sure exactly if they are broken in terms of proper mesh. I believe worms are correct, but in some cases, the worm gear produces invalid self-intersecting geometry. This is actually one of the last two outstanding issues that we are planning to fix before making a stable BOSL2 release but I don't know if Revar knows how to fix it. (He wrote the worm gear code and I don't understand it.) Gears are about 10 times more complicated than it seems like they should be. I believe that all other gear types work correctly, so you might want to try bevel gears next instead of worms and worm gears. On Thu, Aug 22, 2024 at 2:53 PM Nathan Sokalski via Discuss < discuss@lists.openscad.org> wrote: > I am looking to learn how to create & use worm gears using the BOSL2 > gears.scad library (https://github.com/BelfrySCAD/BOSL2). I have used > several of the other components in the gears library in the past > (specifically the spur_gear & rack), although that was my first time using > the library, so I can't say I was necessarily doing it in the most > efficient or intended way. Does anybody know of any good tutorials or > videos on using the worm gear components? In my model I can use the worm > with a rack or with an inverted worm (like a screw, I'm not sure what the > proper term for an "inverted worm" is). Even though it took me a > little while to learn the rack & spur_gear, that was also my first time > using BOSL2 (or any other gear library), so I think I'll be able to learn > the worm a little quicker. Any suggestions for a good tutorial or video? > Thanks! > > Nathan Sokalski > njsokalski@hotmail.com > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

I’m looking for a worm gear too. The BOSL2 gears.scad library (<https://github.com/BelfrySCAD/BOSL2>) “Quick Introduction to Gears” contains 4619 lines of script!!! Won’t that affect preview time? I will have to study that and try to figure it out. Here’s my solution (looks fairly horrible, though). `$fn=100;` `// Looks awful, not awesome` `$vpr=[ 55, 0, -45 ];` `$vpt=[ 4, -4, 0 ];` `$vpd=150;` `/*` `*/` `module gear(num, radii) ` `{ ` `polygon([for (i=[0:num-1], a=i*360/num, r=radii[i%len(radii)]) [ r*cos(a), r*sin(a) ]]);` `}` `// Concave helical gear` `for (i=[-45:1:45])` `translate([0, 0, 6*sin(i)])` `rotate([0, 0, -i/3.5*(1+cos(i))])` `linear_extrude(0.1, center=true)` `gear(24*4, [` `6*(1-cos(i))+12-0.8,` `6*(1-cos(i))+12+0.8,` `6*(1-cos(i))+12+0.8,` `6*(1-cos(i))+12-0.8]);` `// Worm gear` `translate([18,0,0])` `rotate([90, 0, 0])` `linear_extrude(height = 8, twist = 80,convexity=3, center=true)` `gear(12*4, [5.5,6.5,6.5,5.5]);` `// Shafts` `cylinder(r=4, h=60, center=true);` `translate([18, 0, 0])` `rotate([90, 0, 0])` `cylinder(r=4, h=60, center=true);` Any improvement would be most welcome. Some kind of hull function with a restricted effective range might help. The present hull() covers everything.

Processing the BOSL2 code has a negligible effect on preview time, which is dominated by doing actual geometry and not parsing the lines of code. A blank program that loads BOSL2 plus the gears file runs in 6 milliseconds on my computer. Gears are extremely complicated, so getting them right is decidedly nontrivial. Your teeth are trapezoid shaped instead of involute shaped. The two gears in your example intersect each other, so presumably wouldn't mesh. I think linear_extrude with twist has always produced bad results. The enveloping worm gear and worm are particularly tricky to construct. At the moment BOSL2 worm gears are buggy. On Mon, Sep 16, 2024 at 10:57 PM Caddiy via Discuss < discuss@lists.openscad.org> wrote: > I’m looking for a worm gear too. > > The BOSL2 gears.scad library (https://github.com/BelfrySCAD/BOSL2) “Quick > Introduction to Gears” contains 4619 lines of script!!! Won’t that affect > preview time? > > I will have to study that and try to figure it out. > > Here’s my solution (looks fairly horrible, though). > > $fn=100; > > // Looks awful, not awesome > > $vpr=[ 55, 0, -45 ]; > > $vpt=[ 4, -4, 0 ]; > > $vpd=150; > > /* > > */ > > module gear(num, radii) > > { > > polygon([for (i=[0:num-1], a=i*360/num, r=radii[i%len(radii)]) [ r*cos(a), > r*sin(a) ]]); > > } > > // Concave helical gear > > for (i=[-45:1:45]) > > translate([0, 0, 6*sin(i)]) > > rotate([0, 0, -i/3.5*(1+cos(i))]) > > linear_extrude(0.1, center=true) > > gear(24*4, [ > > 6*(1-cos(i))+12-0.8, > > 6*(1-cos(i))+12+0.8, > > 6*(1-cos(i))+12+0.8, > > 6*(1-cos(i))+12-0.8]); > > // Worm gear > > translate([18,0,0]) > > rotate([90, 0, 0]) > > linear_extrude(height = 8, twist = 80,convexity=3, center=true) > > gear(12*4, [5.5,6.5,6.5,5.5]); > > // Shafts > > cylinder(r=4, h=60, center=true); > > translate([18, 0, 0]) > > rotate([90, 0, 0]) > > cylinder(r=4, h=60, center=true); > > Any improvement would be most welcome. > > Some kind of hull function with a restricted effective range might help. > The present hull() covers everything. > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

NopSCADlib also can make involute worm gears. There is a function that gives an involute profile to pass to my thread library. I think it is accurate but I have only used it in assembly diagrams of extruders. I have never manufactured a worm gear from it. On Tue, 17 Sept 2024, 04:26 Adrian Mariano via Discuss, < discuss@lists.openscad.org> wrote: > Processing the BOSL2 code has a negligible effect on preview time, which > is dominated by doing actual geometry and not parsing the lines of code. A > blank program that loads BOSL2 plus the gears file runs in 6 milliseconds > on my computer. > > Gears are extremely complicated, so getting them right is decidedly > nontrivial. Your teeth are trapezoid shaped instead of involute shaped. > The two gears in your example intersect each other, so presumably wouldn't > mesh. I think linear_extrude with twist has always produced bad results. > The enveloping worm gear and worm are particularly tricky to construct. At > the moment BOSL2 worm gears are buggy. > > > On Mon, Sep 16, 2024 at 10:57 PM Caddiy via Discuss < > discuss@lists.openscad.org> wrote: > >> I’m looking for a worm gear too. >> >> The BOSL2 gears.scad library (https://github.com/BelfrySCAD/BOSL2) >> “Quick Introduction to Gears” contains 4619 lines of script!!! Won’t that >> affect preview time? >> >> I will have to study that and try to figure it out. >> >> Here’s my solution (looks fairly horrible, though). >> >> $fn=100; >> >> // Looks awful, not awesome >> >> $vpr=[ 55, 0, -45 ]; >> >> $vpt=[ 4, -4, 0 ]; >> >> $vpd=150; >> >> /* >> >> */ >> >> module gear(num, radii) >> >> { >> >> polygon([for (i=[0:num-1], a=i*360/num, r=radii[i%len(radii)]) [ >> r*cos(a), r*sin(a) ]]); >> >> } >> >> // Concave helical gear >> >> for (i=[-45:1:45]) >> >> translate([0, 0, 6*sin(i)]) >> >> rotate([0, 0, -i/3.5*(1+cos(i))]) >> >> linear_extrude(0.1, center=true) >> >> gear(24*4, [ >> >> 6*(1-cos(i))+12-0.8, >> >> 6*(1-cos(i))+12+0.8, >> >> 6*(1-cos(i))+12+0.8, >> >> 6*(1-cos(i))+12-0.8]); >> >> // Worm gear >> >> translate([18,0,0]) >> >> rotate([90, 0, 0]) >> >> linear_extrude(height = 8, twist = 80,convexity=3, center=true) >> >> gear(12*4, [5.5,6.5,6.5,5.5]); >> >> // Shafts >> >> cylinder(r=4, h=60, center=true); >> >> translate([18, 0, 0]) >> >> rotate([90, 0, 0]) >> >> cylinder(r=4, h=60, center=true); >> >> Any improvement would be most welcome. >> >> Some kind of hull function with a restricted effective range might help. >> The present hull() covers everything. >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >