Quenching gears.
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Previously:
Quenching a pile of hot excavator teeth - GIF
Quenching an anvil in a river, with an excavator - GIF
Quenching an engine block - GIF
Quenching an enormous gear - GIF
Quenching hydraulic breaker bits - GIF
Quenching large gears - GIF
Quenching red hot steel - GIFs
Quenching slabs with holes in them - GIF
