How are tiny screws and gears manufactured?

[Victor Frankenstein]

How are those tiny screws and gears manufactured, do they have some kind of crucible prepared and pour molten metal in them ?

 

[pete worthington]

Screws are often manufactured on screw machines, which are metal lathes that bring in round stock and automatically machine and thread the screws. they can work very fast. I have 13 stitches in my left thumb to prove it !

Small gears could easily be stamped out of steel sheets (like cookie cutters)

The problem with casting is that it typically requires machining afterward.

 

[Victor Frankenstein]

Must they heat the sheets like red hot when they stamp them out, making the metal easier to shape when forming them into gears ?

 

[brewnog]

Must they heat the sheets like red hot when they stamp them out, making the metal easier to shape when forming them into gears ?

Not necessarily. The stamping and machining operations are done separately, - having hot metal for stamping will not intentionally result in the metal being easier to machine.

 

[Averagesupernova]

It is common to cold punch mild steel an inch thick or more.

 

[brewnog]

I would also hazard a guess that having hot blanks would result in more undesirable deformation of the punched part, since elevated temperatures soften most metals.

 

[Danger]

When Victor said 'tiny', I was thinking along the line of wristwatch parts. Are you guys telling us that something that small can be machined?! Can you eleborate upon the machine tools used? I've seen some pretty tiny lathes and milling machines, but nothing that could handle something like that.