Thanks for the comments and suggestions about the animation, Frances and Larry.

I had originally thought about this.
The only way I can animate anything is a gif animation.
For that, I would need to create individual drawings for each frame. This would be worth doing but the real problem would be the reflection on the front face of the gears.

As this is an elliptical fill, I would need to reposition that accurately each time I rotate the gears, a bit at a time.
A bit too time consuming and the end result might not be worth the time and effort. If I can say that with respect.

Other people may have 3D animation programmes, but I don't.

So, at the moment, I am happy enough to have just drawn the gears, considering it started off as a bit of a curiosity on my part! (A most things do with me).