Check out these machined part images:
Orrery
Image by urban don
Fantasy orrery (solar system model) made from junk, scrap metal, buttons, wire, typewriter parts, sewing machine parts, brass spheres, coin, paper, timber, seed pod, paint. Base is 20cm in diameter.
Now available for sale. Please see my profile.
Helical pinion
Image by Elsie esq.
A bit of a long vanished peice of pumping machinary at Kew Bridge Engines in West London