Thursday, 27 March 2008


Re-drew the arms.
They look a lot better now.
And there is a scale to it too.
A strange one but still, a scale.
Took the square root of the distance to the sun in AU's.

Made some pics yesterday.
All what you see here times 8.

The planetary gear box with the drive shaft and the angular gear box

You can see the counting wheels

Angular gearbox and the gears driving the final axes

Top and bottom view...

Bits and pieces....

Saturday, 22 March 2008


I started this a long time ago.
The idea was that each planet would have it's own drive disk.
Stack them all together, drive 8 hollow shafts and Bob's your uncle!
In the real world this was a bit more difficult then it seemed at first.
I had to make enourmous reduction gears to make the far planets move real slow.
And that in real time....
Interesting though.

I found that Tamiya made planetary gear boxes.
You can stack them and configure the ratio you want.

Still needed lots of other gears.
Had to make these myself.

Even then, there is almost no (easy) way of making the exact orbit times.

click on the image to see the calculations

The bigest error is on Mercury.
0.14 degrees off per (Mercury) year.
I can live with that.

The solution:Make some counting wheels and use these to time the rotation exactly.
So you need a little computer to switch the motors on and off.
Can be done.
First I thought about a PLC, now PIC looks the better choice.
I can worry about that later.
Much later.

Some of the drawings:
The drive disk, need 8 of them...
Detail of the shafts with the gears....

Bits and pieces....
Well.. on the screen, that is

When Pluto was considered a "real" planet, I lost interest.
I made only 8 drives and I was not going to do it all again just because of Pluto.

So, thanks to the International Astronomical Union, Pluto is what it is suposed to be:
A stone.
A large one, ok.
But still a stone.
Good, I can start again.