I still say you guys need to print gears on an MSLA resin printer using a dense high durometer polyurethane structural resin. They'd not only look like high quality injection molded parts, they'd be as strong as injection molded parts. Email me an STL and a USPS mailing address and I'll see what I can do.
I finally learned how to engrave text in FreeCAD tonight, so I could put your name on your gear for you. :-) On 6/18/20 1:09 AM, Chris Albertson wrote: > The theory with printed gears is that with helical gears there is more > material in contact so the stress on the teeth is reduced and that for > plastic we need this extra strength. But what I found is that teeth never > fail. The hubs fail first. > > The better reason for helical gears is that they are quieter. But if they > move slow, all gears are quiet. > > Try breaking stuff, it's fun. especially if the material cost only 2 cents > per gram. If you have parts that did not come out as you like. Try > crushing them in a vice, whacking with a hammer or screw it to a shaft and > see what it takes to break the set screw. > > On Wed, Jun 17, 2020 at 9:03 PM Gene Heskett <[email protected]> wrote: > >> On Wednesday 17 June 2020 22:28:22 andy pugh wrote: >> >>> On Thu, 18 Jun 2020 at 03:04, Gene Heskett <[email protected]> >> wrote: >>>>> 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. >>>> That's easy, the teeth in the middle were carrying twice the thrust >>>> load. >>> It isn't that it is that it is kinematically redundant, one of the >>> sets of teeth will see no load at all. >> Or, given manufacturing tolerances it could even dance from one set of >> teeth to the other. I was assuming a perfect make, where the outside >> rows of teeth would be carrying half the thrust load per side that the >> middle row was carrying by itself. But it never got a chance to wear in >> and achieve even that. >> >>> (Though possibly, over time, they might wear to share equally) >> >> 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 >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
