Comments by "Keit Hammleter" (@keithammleter3824) on "How Truck Trailer Fifth Wheels are Made From Old Ships High Strength Sheet" video.

@WhiteWolfeHU : You obviously are not a machinist. It is slow RPM that is more dangerous. At high drill RPM the inertia of the job makes grabs less dramatic, and at high RPM less torque is transferred. Whenever sheet metal is drilled with a drill bit of diameter such that each cutting edge can project above and below the job at the same time (as is the case here), you have a risk of the drill grabbing the job and tearing it out of your hand (and perhaps into the operator).
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He shuts his eyes when the arc is occurring. A lot of Pakistani welders do that. Not very safe - splatter could land anywhere on his face. Sometimes he holds his other hand so as to shield his eyes from the arc. With no gloves, skin cancer may be the eventual result.
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@mathewmolk2089 : The stop , which is a bit of scrap bolted to the drill table in the foreground, probably gives him some false confidence, but the only thing holding the job down is his hand. If the drill grabs, it may wind the job upwards and past the stop before he can react. He's got the drill running at about 300 RPM (5 turns per second), so he has about 1/10 of second to get his hand clear - possible but very risky. The only safe way to drill sheet metal, with drills of diameter larger than the job thickness, is to clamp the job down with dogs and keep your hands well clear - or use a sheet-metal type stepped drill bit, which are not readily available for holes this size.
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No point in painting individual parts - the welding will destroy the paint. Incidentally the red paint is just for appearance. In use it will soon wear off. The black paint on the inside may be rust convertor/preventative as certain types are black - but it might be just black paint.
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