Anyone good with openscad want to design something for me?

Re: Anyone good with openscad want to design something for me?

Ohmarinus — Sat, 04 Jan 2014 17:50:08 -0500

Good idea, I'd love to see this, however, bear in mind that you need a very steady construction.

In the normal side-to-side gear position, the pressure is easily created to keep the teeth hooking into eachother, just by pushing them together and fixing the three bolts through the extruder frame into the stepper motor.

In this beveled fishbone gear setup you would need to have a good force pushing the small gear against the front edge of the bigger gear. This also creates more force on the center of the larger gear, this can be made lighter by adding a bearing on the other side of the bigger gear, adjacent to the small gear's position. However, this will add wear and friction.

In other words, the directional force is completely different and I am not sure if ABS or PLA will be able to hold these forces for a long time without showing considerable wear.

My technical english is very bad, so I'm having a hard time explaining exactly what I mean, I hope you guys understand and maybe a mechanical engineer can tell my story a bit better.

Re: Anyone good with openscad want to design something for me?

MattMoses — Sat, 04 Jan 2014 16:34:45 -0500

Greg Frost's OpenSCAD bevel gears: Parametric Involute Bevel and Spur Gears

I don't think Greg's code will do spiral bevel gears, which you would need as an intermediate to get to herringbone spiral bevel gears.

Re: Anyone good with openscad want to design something for me?

DaveS — Sat, 04 Jan 2014 16:12:31 -0500

fair do's.

I didn't realise it was important it was herringbone !

Re: Anyone good with openscad want to design something for me?

lazzymonk — Sat, 04 Jan 2014 16:03:33 -0500

I have looked alot for something like this. I can not find herringbone bevel gears. I cant even find an openscad bevel gear to try and edit my self

Re: Anyone good with openscad want to design something for me?

DaveS — Sat, 04 Jan 2014 16:00:37 -0500

There's quite a few bevel gears on thingiverse

> for instance <

The above gears move the rotation through 90 degrees, I'm not sure how that helps ?

Anyway.. thingiverse is quite a good first port of call for stuff like this.

regards,

Anyone good with openscad want to design something for me?

lazzymonk — Sat, 04 Jan 2014 13:51:18 -0500

Anyone capable and willing do design something like this? I think it would be good for an extruder. to make it more compact but still good gearing.

220px-Herringbone_double-helical_bevel_gears%2C_Citroens_patent_%28Autocar_Handbook%2C_Ninth_edition%29.jpg

its from [en.wikipedia.org]