Building an Orrery: Bending the Rods

Cut Rods

While the parts were printing I got to work figuring out how to best bend the copper rods that attach the planets to the gears. Ytec 3D provides a printable guide to make sure each part was the right length and shape.

I also had fun figuring out how to best cut the copper, initially for the big centre rod I used a hacksaw but quickly realised this was inappropriate for the rest of the parts. I ended up using my Dremmel which cut the parts cleanly if I was careful to not allow it to bend or snap before cutting all the way through, though this caused the copper to heat up quickly which became a bit of a problem with the smaller length rods. For the very smallest rods I had to use a barrier between my fingers and the copper so I didn’t burn.

Bending the copper rods was also an interesting exercise - I found it best to hold the rod with pliers (ideally non-rib-edged pliers!) while bending a small amount then moving the pliers along the bend, rinse-repeat! This allowed me to follow the bend on the guide much more closely without kinking the hollow copper rods (though I did make a few mistakes - compare Saturn’s rod below with Jupiter’s).

The total print time was 22 hours 14 minutes so when this was complete and I’d formed all my copper rods into the right shapes it was time for assembly! But that’s news for another blog post, stay tuned!