Herringbone Gears for the Robo 3D

Since the Robo 3D uses Greg Wade's (or is it Greg's Wade?) Extruder, it uses straight cut gears. But several reloaded/redesigned versions use Herringbone gears instead.

Do we know what kind of herringbone gears we'd need if we wanted to just do a drop in replacement?

 

I think the original thingiverse files from robo3d had the herringbone gears. they're just hard to injection mold and they dropped them. Lemme see if I still have the files.

 

Thanks Mike.

 

I did a little research and I didn't have any herringbone files. I swore I saw some on there at some point but the last update of their files was 4/4/13 so I don't know for certain.

 

http://www.thingiverse.com/thing:46374 THis little gear
http://www.thingiverse.com/thing:5111 this big gear. Works perfectly. I printed the small gear at a .05 scale OVER to make it fit a bit tighter. Of course, that increases the axle size. Screw requited to secure. Works great

Oh yea.. the hobbed bolt nut is a bit too big, but an easy fix with a sharp knife.

 

Mike you did see some pictures - the original kick starter champaign showed the herringbone gears somewhere.

 

I took the SCAD files, measured the injection molded gears and matched everything as best I could. I have printed both, but the shaft hole on my small gear is a bit small and I haven't taken the time yet to open it up a bit. The SCAD file is the right dimensions, but i think I might have had a bit of shrinkage

Here are the files if you want to try it out. The SCAD and STL files for this version are now posted on Thingiverse. I will be trying my own printed in ABS this week.

 

BTW, this is my first foray into using SCAD, so I probably didn't modify it in the most efficient way possible. Feel free to let me know how to make it more better!

 

In case anyone is interested, I've printed the gears several times, and made several tweaks. I'm now printing full time with them as printed from the files posted at http://www.thingiverse.com/thing:760093. Brief video at .

 

Oops, autocorrupt changed "now" to "not". I am using these full time now. The purple adds a little color, lol.

 

Are 3D printed herringbone gears really better than the molded straight cut ones?
Did it improve a known flaw or problem in your prints?
If they are really that much better, i might print a set on our Objet Alaris and then cast them in resin using a silicone pattern mold. I do this stuff all the time. the very fine resolution and glossy results of that 3d printer are great for reproducible castings.

 

The herringbone gears have virtually no slop during movements and reversals. I like them fur the greatly reduced noise since they aren't "slapping" each other. I think it ends up with slightly more precision for extrusion.


Usin' Tapatalk

 

Are the gears on the R1 okay to print in PLA, or would I be better off using ABS, maybe HIPS?

 

PLA is fine since it shouldn't see very high temps