GD&T and Tolerance Stack-Up for Plastic Parts (ASME Y14.5 / ISO GPS)

Geometric dimensioning and tolerancing per ASME Y14.5 and the ISO GPS system, taught with the plastic-part specifics generic GD&T courses skip: shrinkage variation, warpage drift, and datum schemes that survive molding reality.

Private cohorts & on-site

Format: 2-day (8:30 a.m.–4:30 p.m.)

Level: Intermediate

Location: Scheduled on demand · on-site at your facility or a regional venue

Date(s): Not yet scheduled for open enrollment. Get notified when it is, or book it privately for your team.

Includes: Certificate of Completion · printed slide binder · take-home reference text

Get notified when this course is scheduled

One email when dates are set. Or skip the wait: run it as a private cohort, on-site at your plant.

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Faculty

Faculty details for this seminar will be announced with the full schedule.

Fees

Early: $1,895 (payment 4+ weeks ahead)
Standard: $2,095 (check/ACH) · $2,165 (card)

Group discount: $200 off per attendee for 3+ from the same organization.

Also Available

Corporate on-site delivery at your facility
Private cohort sessions
Digital curriculum licensing

Seminar Overview

A drawing is a contract, and on plastic parts the contract is negotiated between the design intent and what a mold can hold. This seminar teaches GD&T from the ASME Y14.5 and ISO GPS standards — the symbology, datum logic, feature control frames, and tolerance stack-up methods — then adds the layer no metal-parts course gives you: how shrinkage, warpage, and post-molding movement change which tolerances a molder can actually hold, and how to write datum schemes that survive both the CMM and the press.

Tolerance stack-up gets a full day: worst-case, statistical (RSS), and Monte Carlo approaches worked on plastic assemblies — snap-fit engagements, sealing interfaces, connector housing pairs — where the stack includes material-behavior variation, not just machining variation. You learn to allocate tolerance budget across a molded assembly the way a molder will have to defend it.

The differentiator: every concept lands on a plastic part. Datum features chosen for mold reality (parting line, gate location, warp direction), profiles on Class-A surfaces, position on snap-arms, and the translation between Y14.5 and the ISO GPS language your European customers draw in.

Ideal Learner

Design engineers releasing molded-part drawings
Supplier quality engineers reviewing supplier drawings
Tooling and mold-design engineers translating prints to steel
QA/CMM programmers building plastic-part inspection plans

Learning Objectives

Read and apply ASME Y14.5 and ISO GPS symbology on plastic-part drawings
Choose datum schemes that respect mold reality: parting line, gate, warp
Run worst-case, RSS, and Monte Carlo stack-ups on plastic assemblies
Allocate tolerance budget across snap-fits, seals, and housing interfaces
Translate between Y14.5 and ISO GPS when customers draw in the other language

Consulting Sessions

Seminar attendees can sign up for individual consulting sessions with the instructor. Sessions are free for registered attendees, first-come first-served — sign up when registering by calling 248-539-0473 or during the seminar.

Seminar Outline

Y14.5 and ISO GPS: structure, symbology, the rules
Feature of size, datum precedence, material condition modifiers
How a feature control frame actually constrains a molder

Datum selection against shrinkage and warp direction
Parting-line and gate-location consequences
Fixturing and CMM datum simulation on flexible parts
Profile of a surface on Class-A appearance parts

Worst-case stacks on a snap-fit engagement
RSS and when statistics lie on plastics
Monte Carlo with material variation inputs
Sensitivity: which contributor eats your budget

Shrinkage variation as a stack contributor
Warp drift over time: creep and moisture in the stack
Stacking across assembly methods: snap, screw, weld, adhesive
Workshop: allocate the budget on a connector housing pair

Red-line a real molded-part drawing
The molder's rebuttal: what cannot be held and why
Writing the tolerance note that prevents the argument
From drawing to inspection plan: CMM strategy