I said that this machine cost less than $200, but that’s not completely true. The cost of the parts I had to buy that I actually used was around $180. I already had the motor and a lot of other small parts that might total another $30 or $40 to buy.
I spent $150 or so on things I didn’t end up using – the Logitech webcam, the AC motor speed control, white LEDs, etc. That’s the cost of engineering, but it doesn’t count as the “direct cost” of the finished machine. The items are still usable or salable.
Last, but certainly not least, is the lens. I’ve not seen a 17.5mm Baltar for sale on Ebay or anywhere else, so I don’t know what it would cost. If I didn’t have that lens, I would shop for a similar 8mm or 16mm movie camera lens. I tried a cheap Chinese 16mm CCTV lens, but it was not very good.