Tolerances & Fits
Tolerance Stack-up Analysis
Calculate worst-case and statistical (RSS) tolerance stack-up for linear dimension chains with up to 8 components.
Units:
Worst-case method guarantees all assemblies work but is conservative. RSS (Root Sum of Squares) method is statistical — assumes normal distribution, 99.73% of assemblies will be within tolerance (3-sigma). Use RSS for high-volume production.
WC: T_total = sum(Ti) | RSS: T_total = sqrt(sum(Ti^2))
Input
Tolerance T1 iBilateral tolerance of component 1 (half-value, e.g. 0.1 means +/-0.1mm).
mm
Tolerance T2 iBilateral tolerance of component 2.
mm
Tolerance T3 iBilateral tolerance of component 3. Set to 0 if not used.
mm
Tolerance T4 iBilateral tolerance of component 4. Set to 0 if not used.
mm
Tolerance T5 iBilateral tolerance of component 5.
mm
Tolerance T6 iBilateral tolerance of component 6.
mm
Nominal gap / clearance iNominal (target) gap or clearance in the assembly in mm.
mm
Result
Active tolerances
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Worst-case total tolerance [mm]
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RSS total tolerance (3-sigma) [mm]
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Min gap (worst-case) [mm]
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Max gap (worst-case) [mm]
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Min gap (RSS / 99.73%) [mm]
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Assessment
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