It's only when the wood gets wet (from rain, dew, or poor handling of the hose) that tannins convert into tannic acid. If you've used ferrous or steel nails, the acid reacts with the iron ...

Curious about how iron nails are made? Watch this fascinating process as machines churn out hundreds of nails in a factory. From shaping the raw iron to finalizing the nails, every step is streamlined ...