Tolerance and Why ±1/32" Matters

"Measure twice, cut once"

What Is Tolerance?

Tolerance defines how far a part can deviate from its intended dimension while still working correctly.

Example:

• 10.000" ± 1/32"
• This means the part can be slightly larger or smaller and still be acceptable

Why ±1/32" Matters in FRC

A tolerance of 1/32 inch (0.031") may seem small, but in robotics it can:

• Prevent holes from lining up correctly
• Cause shafts or bearings to bind
• Create misalignment in drivetrains or elevators
• Stack into larger errors across assemblies

Small errors add up when multiple parts depend on each other.

When Tight Tolerances Are Needed

Tight tolerances (like ±1/32") are important when:

• Aligning bearing holes
• Mounting shafts or gears
• Building drivetrain frames
• Connecting pre-cut or CAD-matched parts

When Loose Tolerances Are Acceptable

Looser tolerances are acceptable when:

• Mounting non-critical brackets
• Creating sensor mounts with adjustment
• Working with slots or oversized holes
• Designing parts that need adjustability

Best Practice

• Measure twice before cutting or drilling
• Use the same datum for all features
• Center punch hole locations before drilling
• Drill pilot holes before final sizing when precision is critical

Key Idea

Tolerance is not just a number—it is what determines whether parts fit together correctly or create assembly problems. In FRC, ±1/32" can be the difference between a smooth assembly and a misaligned mechanism.