Iron Man in a bottle.

[oldvan]

This Guy Covers Black Sabbath's "Ironman" With A Bottle Bass Guitar...

OK, not a huge lot of machine skills were needed to make that, but still pretty cool!

[spro]

Action which is masked at the beginning. It would seem the bass and music covered up what he was doing until later. Then it was him. His action and passion was evident. This guy had some callouses on his fingers and put hisself into it, drawing out the tonal abilities of nontonal by force and concentration. One could say he needs a guitar or something but this fellow hammers out and imagine the gauge of those strings. My little baby fingers would be very sore-and they are not even babies.
There was consideration about the neck and a straight piece of what I hazard to guess.