Smaller electronic mechanisms reduce available travel and magnify the effect of plastic tolerance, contamination and contact wear.
Use a tolerance stack for travel
Combine housing, PCB, battery, contact and spring dimensions to confirm sufficient force without overload in loose and tight assemblies.
Contact geometry affects stability
Sharp points create pressure but concentrate wear, while broad contact is stable but may not break surface films. Match geometry to vibration and insertion.
Material and finish define electrical behavior together
Conductivity is only one metric. Include hardness, wear, joining, corrosion and long-term stress relaxation.
Validate the assembly
Drop, vibration, temperature-humidity and powered tests in the actual housing and mating parts often reveal more than isolated spring-load checks.
References
This article is informed by public standards catalogues and industry engineering resources. Project values should be confirmed by drawings, material certificates and sample validation.