You can make a double-helical by downloading a left and a right helical and sticking them together. You do not even need to know what "involute" means as you just cut and past from McMaster Carr. Just keep faith that they know how to design exotic stuff like spiral bevels, they do.
Designing gears got so much easier when I found that all the gear resellers give away their designs. One other big advantage yo downloading a stock gear is that later when you need a metal version of thegear, you know you can get one. In theory, you should be able to mill these exotic gears on a mill if only you had a small enough ball end mill. It makes take a week. About printed gears. One thing, just don't try for smaller than about module 1.0. Yes, 0.5 will mesh but the error in shape is high as they get smaller. On Wed, Jun 17, 2020 at 6:44 PM andy pugh <[email protected]> wrote: > On Thu, 18 Jun 2020 at 02:23, Gene Heskett <[email protected]> wrote: > > > There's a parametric gear thing I have but its a sample of many gear > > styles and I don't know how to cut it apart and use just the external > > spur piece of it. I need something that openscad can handle. > > You could take OpensCAD out of the loop, I suspect, and print the > gears from the stock part models from (for example) McMaster Carr > > Or you could tell me the centres, tooth size and PCD you need and I > can send back a model from Inventor in not much time. > > But why use spur gears? One thing that 3D printing is good at is > double helicals. > > Or even triple, or quad. But those are stupid: > https://images.app.goo.gl/ZbZBVWoBEnRbPL469 > > Note, these are a daft idea. But I have actually seen a 9 foot > diameter triple helical in my dad's old workplace. He did need to > explain to me why it was silly, and why they refused to replace it and > specced a double instead. > -- > 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 > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
