GD&T
Tolerance stack-up
Builds a worst-case and statistical stack-up along a defined loop, ranks contributors by share of total variation, and tells you which two tolerances to tighten or which can be opened for cost.
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Top contributors
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Anders HolmZEISS Industrial QualityTolerance Analyst
Daniel WeberMathWorksApplication Engineer
Hiroshi TanakaToyotaReliability Engineer
Julien DuboisInstronTest Engineer
Kenji AoyamaMitutoyoGD&T Specialist
Lars EkstromNord-Lock GroupBolted Joint Engineer
Marco BelliniXometryCost Engineering Manager
Marcus ReedProtolabsManufacturing Engineer
Showing 12 of 12 sheets
Rev. Q3 2026
GD&T
GD&T callout review
Reviews a drawing's geometric tolerancing for legality and intent: datum precedence, degrees of freedom actually constrained, redundant or missing controls, and whether the callout can be inspected.
FEA
Bolted joint sizing
Sizes and verifies a bolted joint end to end: preload, stiffness ratio, separation and slip margins, fatigue on the alternating share, and a torque spec with the friction assumption written down.
FEA
FEA sanity check
Audits a simulation before anyone trusts it: reaction balance, hand-calc cross-check, singularity screen, convergence, and whether the reported stress is even the right quantity for the criterion.
FEA
Hand calc check
Produces a documented first-principles calc sheet for beams, shafts, buckling, pressure, fits, springs, and bearings: assumptions numbered, units carried, margin reported against a named criterion.
Manufacturing
DFM review for machined parts
Walks a machined part for manufacturability: setup count, internal radii, deep pockets, thin walls, workholding, and the tolerances that quietly force secondary operations and triple the price.
Cost
Supplier quote review
Normalizes supplier quotes to common scope and terms, builds a bottom-up should-cost from material, cycle time, and tooling, and identifies the specific line items worth negotiating.
Materials
Material selection tradeoff
Runs an Ashby-style selection: screens candidates on hard constraints, ranks on the right material index, states the failure mode each finalist is weakest against, and recommends grade and temper.
Quality
DFMEA builder
Facilitates a Design FMEA that teams actually use: function decomposition, physics-of-failure brainstorming, honest severity and occurrence scoring, and verifiable actions in RPN or AIAG-VDA format.
Quality
Root cause and 8D
Drives a disciplined failure investigation: is/is-not problem definition, mechanism-first causal analysis, verified root cause with evidence, and a complete 8D covering technical, escape, and systemic causes.
Testing
Test plan builder
Converts requirements into a verification matrix with pass/fail criteria, statistically based sample sizes with stated confidence, test sequencing, and the gaps where a requirement is untestable as written.
Documentation
ECO writer
Drafts a complete engineering change order: itemized before/after, the interchangeability call, an exhaustive affected-items sweep, stock disposition, and the validation required before release.
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