Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


Can someone help me with my Planetary Gear Set.

Can someone help me with my Planetary Gear Set.

Can someone help me with my Planetary Gear Set.

I do not understand why this is not meshing correctly.

CAD Link

I calculated:
Sun Gear: 12 Teeth
Planet Gear: 9 Teeth
Ring Gear: 30 Teeth

Gear Ratio: Ring Held Stationary
Between Sun and Planet: 12/9
Between Sun and Carrier: 12/42

Would Appreciate the Help!!


RE: Can someone help me with my Planetary Gear Set.

In part it is because your software is not turning the gears at the correct ratio. Maybe you are not correctly adding/subtracting the angle the carrier turns from the angle the planet gear needs to turn to keep correctly meshed with the sun gear.

For each clock-wise turn of the carrier, the planet will make 1 turn clock-wise + 30/9 turns counter-clockwise.

RE: Can someone help me with my Planetary Gear Set.

Do you want to know why the gears in your cad simulation do not seem to be synchronized in rotation? Or do you want to know why there is interference between the gear tooth profiles as they pass in/out of mesh?

With regards to the latter, your epicyclic with a 12T sun, 9T planet and 30T ring requires a fair bit of tweaking to simply mesh without interference. Getting the gearset to mesh "smoothly" will be a far more difficult task.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close