Switch gap and adjustment targets

Normally open switches want about 1/16" between contacts when open, then keep wiping once they touch. Normally closed switches also want about 1/16" when open, with wiping. Make/break switches are hardest. Aim for each contact to make or break at the halfway point of its actuator's travel, on relays and playfield switches alike.

Systems

• Electro-mechanical

Related tips

• Self-cleaning "over-wipe" switch adjustment
• New to EMs? Do not adjust switches that work
• Why EM switch contacts get dirty
• File EM switch contacts
• Tighten a switch stack before adjusting it
• Adjust a leaf switch at the stack
• Normally open, normally closed and make/break switches
• Look over every switch before first power-up

Source: Repairing Electro-Mechanical (EM) Coin Operated Games to 1978, Part One, Clay Harrell (pinrepair.com)