Codger_64
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- Joined
- Oct 8, 2004
- Messages
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Upstream said:..... How they could make stamps so small is a wonder to me.
Photoetching. I used to do it. A soft steel stamp blank is coated with a litho coating, covered with a film image of the stamp, placed under vacuume, and exposed to intense arc lamps. The coating exposed to the light bakes and hardens, the area to be removed is covered by the film and remains soft. A photodeveloper solution washes away the soft coating, and cures the hard coating. Acid is scrubbed over the surface to eat away the soft steel evenly where not protected by the coating. Then the acid is neutralized and the coating removed, the steel shank shaped, the steel tempered and hardened beyond the rockwell of the target steel to be impressed. Bang! A tiny tangstamp. Probably do it with CNC machines or lasers this century though. Then there is the leprechaun theory.
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