View Full Version : One for all of you gear crazies

Spin Doctor
01-24-2008, 05:26 PM

A stunning piece of work

01-24-2008, 05:55 PM
I saw that over at PM -- what a beauty!


01-24-2008, 06:05 PM
Wow! And just when we I thought it was incredible, I noticed that he/she also has our moon revolving around us. Those moon outrigger (gears/U-joint/other?) must be minute.:eek:

01-24-2008, 10:52 PM
There's a great quote in the article:
"At present, I don't even use CAD software. All G-code was generated by my own C++ programs."

That's like saying I'm not a rocket scientist, I'm just a brain surgeon.

01-24-2008, 11:06 PM
Wow! And just when we I thought it was incredible, I noticed that he/she also has our moon revolving around us. Those moon outrigger (gears/U-joint/other?) must be minute.:eek:
Gerald...I'm betting he used bevel gears or maybe those square tooth gears like you see in old clocks. U-joints don't seem to fit into his theme. I'd use playdough :D

01-25-2008, 09:14 AM
Video of the construction process and working model at http://www.youtube.com/watch?v=w56smGCCiKI .

01-25-2008, 10:39 AM
That looks interesting. I have been planning to build an orrery for quite some time and it is on the list now with my CNC mill running. The cool thing is that if you can draw it, within reason you can make it. I just made this for fun the other day. The best part of CNC is that you can make things that are totally impractical to make otherwise.


Spin Doctor
01-25-2008, 05:37 PM
Well Evan I can see one way to manually make the impeller sitting on your keyboard. All it takes is a rotary table and some way to index the part. The centerline of the part would have to be offset from the centerline of the rotary table with the indexing device being on the same centerline. Crank the RT through the first cut. Reverse direction. Index to the next position and make second cut. Now just keep doing this For the other side of each vane change the set-up and repeat. Just how did you do it. Cut the first vane and do a rotate command?

01-25-2008, 05:43 PM
The vanes are not circular. They're a higher-order curve. Your method would definitely produce some kind of vane, but you'd have no control over the shape.

01-25-2008, 05:45 PM
Whats that impeller going into?

01-25-2008, 09:52 PM
Evan, did you upgrade to mach 3? the impeller is impressive, thanks for sharing, tom

01-25-2008, 10:12 PM
Whats that impeller going into?

It's for the blower for his desktop titanium foundry. When you're building 150,000 RPM rotors for your 200 Wh/kg flywheel energy storage system, you have to use appropriate materials.

01-26-2008, 12:07 AM
It isn't for anything. It was an experiment and it was done with TCNC. I am upgrading to Mach 3, I just need to find time to shuffle computers around. Maybe tomorrow.

It's true, the vanes are not a simple curve. One side is but the other is slightly parabolic.

I didn't mean to hijack the thread, my point was that complex and impressive looking work can be made just by drawing it. I'm impressed by the orrery. I would like to build one that actually is a real orrery in that it displays the actual positions of the planets in relation to each other in real time. You wouldn't have the fun of watching it move but that isn't what it would be for. I want it to see at a glance where things are in the sky.

01-26-2008, 08:11 AM
This is real art.

Try making these items.




And all of these too.

Spin Doctor
01-26-2008, 09:56 AM
Years ago Fine Woodworking had an excellent article on making wooden clocks. I had it and now i don't

01-26-2008, 11:41 AM
The Germans and the Brits built the stuff way before CNC. However, I do agree about the practicality issue.

One interesting thing about CNC is all the tools it means you don't need any more. There are so many things we have that are just there to simplify machining in a manual world. The savings in not having all that tooling more than pays for a CNC retrofit of a machine.



01-26-2008, 11:44 AM
Mick sent me those pictures by PM earlier. Simply amazing craftsmanship:



01-26-2008, 12:03 PM
Those are amazing, especially the telescope.

This thread is good in that it is making me think about exactly what I would like to build in the way of an orrery. One of the problems with such an instrument is that it is difficult to display. It simply takes up a lot of space if it is any size at all and it's fragile as well. This has me thinking of building one that is somewhat more two dimensional with disks to represent the planets etc and making it so that it can be installed and protected in a wall hanging shadow box with a glass front. There would still be plenty of opportunity to show off the mechanism. It would be in essence a solar system clock, which is what an orrery is.