Page 134 - CITS - Electronic Mechanic - TT - 2024

ELECTRONICS MECHANIC - CITS

connectionto a large area. A concave tip well is said to help prevent bridging of closely spaced leads; different
shapes are recommended to correct bridging that has occurred. Due to patent restrictions not all manufacturers
offer concave tips everywhere; in particular there are restrictions in the USA.Older and very cheap irons typically
use a bare copper tip, which is shaped with a file or sandpaper. This dissolves gradually into the solder, suffering
pitting and erosion of the shape. Copper tips are sometimes filed when worn down. Iron-plated copper tips
have become increasingly popular since the 1980s. Because iron is not readily dissolved by molten solder, the
plated tip is more durable than a bare copper one, though it will eventually wear out and need replacing. This is
especially important when working at the higher temperatures needed for modern lead-free solders. Solid iron
and steel tips are seldom used because they store less heat, and rusting can break the heating element.

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CITS : E & H - Electronics Mechanic - Lesson 69 - 72