Worst-case & RSS
Tolerance stack
Inputs
Nominal one-dimensional result before contributor variation.
Symmetric stated tolerance magnitude for the first contributor.
Symmetric stated tolerance magnitude for the second contributor.
Symmetric stated tolerance magnitude for the third contributor.
Optional visible contributor; enter 0 when unused.
Optional visible contributor; enter 0 when unused.
Optional visible contributor; enter 0 when unused.
Results
Worst-case stack tolerance
0.18
RSS stack tolerance
0.11576
Worst-case lower result
99.82
Worst-case upper result
100.18
TWC = Σ|tᵢ|; TRSS = √(Σtᵢ²), up to six visible contributors
A first-pass number, not a code check, certification, or approval. Read the method and its limits below. What this is and is not.
Nearby: ISO 286 fits · Position deviation · MMC bonus & virtual condition · Process capability Cp/Cpk
Method
Formula, when it applies, and when it does not
Compare up to six visible independent symmetric contributors using explicit worst-case and root-sum-square stack methods.
TWC = Σ|tᵢ|; TRSS = √(Σtᵢ²), up to six visible contributors
When
- Linear one-dimensional chain
- Independent contributors for RSS
- Symmetric stated tolerances
- Up to six user-entered contributors
Don’t
- RSS is a statistical combination only when contributors are independent and the stated distribution assumption is justified. This is a linear one-dimensional stack, not a complete GD&T or assembly analysis; it makes no compliance, yield, or tolerance-recommendation claim.