Parent Child

I am trying to make my 3D version of a 2D gear. I created a parent child relationship between the 2D gear and the 3D gear but the child is not rotating in the same position as the parent and I don’t know how to change this. I want the Child to rotate in the exact same spot as the parentRotary to linear Gear.3dm (997.8 KB)

just move the 3D on the 2D
Rotary to linear Gear 002.3dm (944.7 KB)

Sure hope you don’t mind some tutoring on your model.

Firstly; I was struck by the number of keyframes in you model, observing that the nature of the movement of the gear (as well as its rotation) is obvious quite linear and could be managed by 6 keyframes. I assume you have been hoaxed by the default tweening ‘Cardinal spline’ combined with the ‘Automatic Easing’ (by default enabled) and that you tried to compensate its effects through a variety of keyframes.
It is far more convenient to simply keep the basic keyframes (0, 32, 37, 77, 82 and 90) and alter their tweening settings. This can be done in the Keyframe Editor, most swiftly in one go after selecting all the keyframes. You set both Curve path and Travel to Linear and disable Automatic Easing.
The result is in Rotary Gear revised.3dm (1.0 MB).
You can read more about tweening on Bongo’s website

Secondly; I revisited your ‘Animation Not Working Right’ topic on the forum.
The inputs of scottd and schultzeworks are surely true. But in your case you can simply unify the 3 elements of the pinion (sprocket, shaft and roundel) by using Rhino’s Union command. Once ‘United’ they are in fact one object. As far as I can see Blocks are only interesting when you have more than one instances of an element, or when you want to combine objects with various material properties.
The BongoMovePivot command is still in order to move the pivot in the center as Marika pointed out in your ‘Can’t get gear to rotate around its center’ topic.
The same Boolean Union can be used on the rack parts – although not necessary since it doesn’t move.

Keep it up!

Thank You!

My pleasure.