In article ,
David Lesher wrote:

A slight OT query....

How are pressure cylinders such as SCUBA tanks and "K Bottles"
manufactured? Some are aluminum, others steel. I'd assumed they're cast
in one piece, but I don't know for sure, and someone asked me..

Search around in YouTube a little... I just saw some videos of SCUBA and
other tanks being fabricated a couple of weeks ago.

Erik