Welding metal with friction: Strangely satisfying

[Marcus]

[HunterTodd]

I did something similar when I ran the wheel bearing out of grease on the horse float. MDon't think the bearing is supposed to be welded to the  axle though!

[West Aussie Glen]

Another use for friction.

http://www.flowdrill.com/

[Biggles]

Another use for friction.

http://www.flowdrill.com/

That's an impressive hole maker!
I suspect there are some extremes involved- the hardness of the "bit" and the pressure on the drill to cite two.

[West Aussie Glen]

Another use for friction.

http://www.flowdrill.com/

That's an impressive hole maker!
I suspect there are some extremes involved- the hardness of the "bit" and the pressure on the drill to cite two.

I have seen it in action for something around 8 mm and minimal downward pressure required, just a standard drill press. The metal is annealed by the heat of the friction and then the tapping just deforms the metal to form the thread and work hardens it. There is no metal lost.

[Biggles]

I have seen it in action for something around 8 mm and minimal downward pressure required, just a standard drill press. The metal is annealed by the heat of the friction and then the tapping just deforms the metal to form the thread and work hardens it. There is no metal lost.

There must be something going on since a blunt bit won't drill metal no matter how hard you press down on the drill.  High speed?