Saturday, August 6, 2011

Detailed Orrery Plans

It has been almost 2 years since my last post, which included the promise of more detailed plans at some stage, probably in a pdf. Well, obviously that didn't happen, but, I have gone one better. If a picture is worth a thousand words then I guess a detailed 3D model might be worth a few hundred pictures at least.

I'm preparing to refurbish the orrery using something a little more durable than superglue and a little more accurate than a dremel tool held by hand. As such, I needed plans. Using Google Sketchup, a free 3D modelling tool, I have created a model of orrery that is completely scale accurate. (Unfortunately, since both the pipes and the gears were in imperial, the whole thing is also in imperial scale, apologies to the 95% of the world who uses metric.) There are two versions of the model, first completed:

And also exploded:

As you can probably see from the pictures here, I have coloured the pieces so that groups of elements that are physically attached to each other are the same colour. Hopefully this will make it much easier to tell how the whole thing is put together.

A couple of notes, the worm gear is represented here just as a cylinder, couldn't work out how to generate that in sketchup. Also, I have omitted the chain between the two sprockets, again a little too fiddly. The two large gears that aren't actually touching each other are the sprockets. Finally, the gears aren't always directly connected to the tubes because the bore holes are often larger. As I mentioned previously in the blog, I would connect these by cutting small sections of tube up to fill in the bore hole.

For those of you who haven't played with Sketchup before, it took me all of about 2 hours to go from no idea to able to put together decent models. I downloaded it 3 weeks ago and have put this together in spare time since then, so it's pretty easy to find your way around.

Hopefully in the coming months I will have updates with the rebuild process of the orrery. In the meantime, for those of you out there trying to build this (and I've heard from about a dozen of you, with at least one almost finished), I hope this model makes life easier.