Loading
stewartde

Herringbone Planetary Gear/Bearing (Optional HoneyComb) (Customizable)

by stewartde Aug 14, 2015
Download All Files

Thing Apps Enabled

Please Login to Comment

I am working on designing bearings to mount a filament spool on the stock spool holder for the Ender 3D. A few options in the customiser would make it much easier. I have not found a way to disable the honeycomb, which tends to complicate the design, and the planetary gears always seem to have a hollow hex centre that I can not remove.

To remove the Honeycomb set:
Infill hole size = 0
Infill strength = 100
To remove the center Hex set:
Center Hex Hole Width = 0

I just tried it in the customizer and it worked.

I found the infill hole size, that definitely helps

I get the problem of the planet gears being easy to remove from the assembly. I can not go much lower on the tolerance.

How could I go about increasing the thrust resistance (correct me if I'm wrong) of the gear? I would like to go with bigger teeth pitch size but I cannot find any setting in the scad file, maybe more twist would also help.

Anyone have some guidance for me?

decreasing the pressure angle increases the "depth" of the teeth, that will make the gear less like to fallout using the same tolerance

Try the "Open in Customizer" option.
There are many settings and some will help with thrust mechanics.

Thanks for introducing me to customizer and for all your work - that must be a lot of work on the backend.
Customizer is still "working" but I look forward to trying the very compact version (30 mm) which I plan to try to use in a bigger project test.
Again, thx.

Awesome, thank you.
I also used this within bigger projects as well.
Please let me know how yours works out.

I used the file supplied with no alterations, and made it out of PLA.
The gears were so sloppy, they skipped teeth....
I would like to know how to correct this problem

If you select the "Open in Customizer" there is an option for "Clearance (separation between the gear teeth)" that is defaulted to 0.4. You can simply adjust that value to make the teeth as close as you like. Then you can choose to "Create Thing" and then save that file for your own printing. Also, since many others have made successful prints without spacing issues, you should consider looking at your 3D printer extruder settings for Nozzle Diameter and other settings. As "Flip35" pointed out in his comment below, "It's also perfect to test your settings due to the detail of the new gears infill honeycomb pattern." I know that 3D printer rigidity also plays an important role in the quality of the printed items. I hope that helps.

I was wondering if you could add a customizer feature or display somewhere (never having used it before I do not know if it is possible) that would calculate the gear ratio. This does have some benefit as a gear reduction system.

The algorithm I know of to calculate planetary gear ratios for a driven sun gear and stationary ring gear is (revolutions of the planet gears):
Sg / (Rg+Sg)

Where:
Sg - Sun gear teeth
Rg - Ring gear teeth

It is just sometimes difficult and always tedious to count the teeth :)

I think one problem would be that you can attain the same ratio using different teeth counts. Also, the really cool thing about planetary gears is that you can use the ratio between the sun, the planets and the ring separately and also it depends if the ring or sun is held stationary. For example, take a look at the "Automatic Transmission Model" item by emmett, published Nov 17, 2012 http://www.thingiverse.com/thing:34778 If you watch the video you can see that changing which piece is used and which piece is held stationary will change the ratios. Writing SCAD code to handle each of them would complicate the code beyond my ability to manage it nicely. However, the SCAD code is freely available to you in the "Thing Files" download section. You can adjust the SCAD code yourself to handle creating the tooth count and set the variables the way you like. Sorry I couldn't be more helpful.

Automatic Transmission Model
by emmett

I think something got lost in translation. I say this because of the comment portion "same ratio using different teeth counts"

I did not mean the ratio is an input only an output. Just "display somewhere ... the [calculation of] the gear ratio"

That way one does not have to manually count teeth to figure out what the ratio is going to be :D

Can I put my name on it??

I'm sorry, there are no built in options for adding text. You would have to add that separately after you create the final 3D model.

One of my first successfully printings.

As it is now and without any customization works out of the box. No torque needed.

It's also perfect to test your settings due to the detail of the new gears infill honeycomb pattern.

Thanks.

Comments deleted.

This is awesome! Thanks for sharing!