Historical clue formulations

• Join, as two metal surfaces — 2026-08-30
• Metalworker's union — 2024-03-16
• Do some bonding — 2021-07-16
• Lead-tin alloy — 2019-10-03
• Electrician's alloy — 2017-10-02
• Unite, in a way — 2013-03-13
• Electrician's alloy — 2010-07-20
• Electrician's alloy — 2009-03-24
• Joining alloy — 2009-02-11
• Electrician's alloy — 2000-12-12
• Lead-tin alloy — 1998-09-16
• Plumber's need — 1995-04-25