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Benjamin Reese

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3 Tools to Tackle Tough Tolerance Negotiations - Using Data to Support Tolerance Changes

3 Tools to Support Tough Tolerance Negotiations 

DCS Solutions offer a number of tools to support your tolerance discussions with customers. 

Tolerance Negotiations are never easy. Customers will try to hold their suppliers to difficult or over-engineered tolerances, or simply don't know that certain tolerances can be opened without affecting the assembly quality, or need to be opened (increased) in order to keep costs reasonable. 

DCS provides 3 tools to support tolerance negotiation by using data to back up tolerance change requests: 

1. Tolerance Negotiator -- QDM Analyst Tool

2. 3DCS Variation Analyst Simulation Results

3. QDM Management Reports 


1. Tolerance Negotiator - QDM Analyst Tool 

How do I get it?

Tolerance Negotiator is built into the base QDM Analyst software, without the need for add-ons or additional purchases. If you have QDM Analyst, the standalone QDM template maker software, you have Tolerance Negotiator. 

Using Tolerance Negotiator

Tolerance Negotiator is under the Tools tab of QDM Analyst. 

After clicking Tolerance Negotiator, a table with all of the imported data measurements is generated.

Two types of data are usually used in Tolerance Negotiator.

Plant and Measured Data can be imported from any inspection device and used to demonstrate production tolerances and metrics. Suppliers use the first 30 parts in a production line, or prototype measurements to demonstrate measured values and whether they are meeting or failing to meet statistical objectives (Pp or Cp). 

Simulation data from an analysis tool can also be used before production. As a DCS Software, QDM is already configured to utilize 3DCS data. Importing 3DCS simulation results can show the risk of failure for given objectives. 

Tolerance Negotiator gives two sets of values:

1. Tolerance changes required to meet given Cp / Pp objectives

2. How Tolerance changes affect Cp and Pp 

This lets the user change tolerances, values and objectives and instantly see the results. For example, if your customer gave a required Pp of 1.33, you can show which tolerances in the provided design can actually meet that objective. With 3DCS, you can demonstrate how 3D stack ups affect those tolerances and further determine the final Pp or Cp values, and may affect the final range of variation. 

Tolerance Negotiator Demonstration

The video below demonstrates how the use of Tolerance Negotiator:


2. 3DCS Variation Analyst Simulation Results

3DCS Variation Analyst simulates assembly builds across a normal distribution (default) using Monte Carlo Simulation. Incorporating part tolerances and assembly processes, 3DCS provides outputs of simulated measurements that include the 3 dimensional variation stack of all parts and processes in the model. 

The results are the measured results of hundreds or thousands of virtual product builds compiled and analyzed statistically. Beneath the simulation results are the sensitivity results, which include the largest contributing tolerances to the given measure. 

In the simulation results window, upper and lower specification limits can be dragged to adjust and see the statistical outputs, Cp and Pp, change accordingly. It also demonstrates the expected failure rate for each given measurement with its given specification limits. This information can be valuable in showing the risk of build failure for each feature based on current design specifications, and how changes can affect either the Cp/Pp or the risk of failure. Adjusting a tolerance and re-running the analysis can show the change to the simulation results and whether an adjustment will positively or negatively affect the model outputs. 

Here is a video example of one method of how 3DCS simulation results can be used for tolerance negotiation: 


3. QDM Management Reports

QDM Management Reports are an effective way to present results to managers and business leaders. They summarize and display simulation or production results, giving visual context and information to make it easy to understand the content. 

Within the reports, as part of tolerance negotiation, a user can set specification limits or pass/fail criteria and color coding to show whether given measurements passed or failed inspection. 

This is a good way to show simulation results from 3DCS or production data in QDM and whether those simulation results will meet quality expectations. It can be helpful for pointing out trouble areas and leading into a tolerance negotiation on resolutions for those given measurements and tolerances. 

Learn more about Tolerance Negotiation and Supplier Quality with Supplier Quality for Suppliers Webinar - FREE On-Demand 

Click to View the Webinar

Topics: PTC Creo 3DCS Creo Siemens NX QDM Webinar CATIA V6 SPC Tolerance Analysis 3DCS CATIA

Webinar Nov 29 - Supplier Quality...For Suppliers - Learn How a Connected Quality System Helps Suppliers Meet Market Demands

Setting Up Supplier Quality Assurance for Tier 1 Suppliers

Many Tier 1 Suppliers support different customers with different expectations and needs. A well implemented quality assurance system can make it easy to meet these different expectations, with monitoring, communication and problem solving built in to the system. 

In today's demanding automotive marketplace, OEMs rely on large Tier One suppliers for major systems across vehicle platforms.  This in turn has put the onus of validating parts on the Tier One.  OEMs demand high quality systems - Tier Ones have to demand high quality parts from their supply base to put into those systems.

Topics: QDM Webinar SPC Press Release

How to Design and Optimize Datums in 3DCS Tolerance Analysis Software

Datum Design and Optimization in 3DCS Tolerance Analysis Software

Datum design and optimization is the most important step in any assembly quality control process which can be simplified by evaluating the geometric factors and concerned variations.

DCS has already covered creating Datums in the CAD platforms - CATIA, NX and CREO, but what about verifying those Datums and optimizing them? 

Topics: 3DCS Creo Siemens NX PTC Creo DE Focus Tolerance Analysis CATIA 3DCS

Model Variants - New for 3DCS Tolerance Analysis! Create Different Tolerance, Assembly and Tooling Configurations in One Model

New For 3DCS Tolerance Analysis Software - Model Variants

The Upcoming Version 7.6 of 3DCS offers the ability to create Model Variants - Different configurations of Moves, Tolerances and Tooling in the same model to test and validate processes. 

In design, different methods of assembly, tolerance schemes, and tooling / fixturing need to be considered. Oftentimes, on the same model, there are a plethora of assembly processes that can be used to achieve the same end result. Some of these processes cost more, some are more complicated and some require special skills. The question Designers and Engineers ask when designing their product is; which process and what tolerance should I use?

Topics: PTC Creo 3DCS Creo Webinar Siemens NX CATIA V6 FEA Tolerance Analysis 3DCS CATIA

Digital GD&T Webinars Part 2 and 3 Now Available On-Demand


Topics: PTC Creo 3DCS Creo Siemens NX QDM Webinar CATIA V6 SPC Tolerance Analysis 3DCS CATIA

Realizing the Value of GD&T in Model-Based Definition

Realizing the Value of GD&T in Model-Based Definition

Create better products and designs while saving money and reducing scrap

This is a preview of the article featured on Quality Digest by Gary Bell, DCS Sr. Dimensional Analyst

Topics: PTC Creo 3DCS Creo Siemens NX QDM Webinar CATIA V6 Tolerance Analysis CATIA 3DCS

Webinar Thursday - Quality 4.0 - How CAD GD&T Drives Model Based Definition with 3DCS Tolerance Analysis Software

Quality 4.0 - How CAD GD&T Drives Model Based Definition with 3DCS Tolerance Analysis Software

Learn how 3DCS connects processes from GD&T to measurement planning to final problem solving in production. 

DCS in partnership with Quality Digest will be presenting Closed Loop on Thursday, October 25th, 2018 at 2 PM EST. 

Topics: Press Release PTC Creo 3DCS Creo Siemens NX Webinar QDM CATIA V6 Tolerance Analysis 3DCS CATIA

GD&T Applications Webinar Tomorrow! Learn from DCS' ASME Certified Trainer how to handle GD&T Scenarios

GD&T Applications Webinar Tomorrow! 

GD&T Applications

WEDNESDAY Oct 17, 11 am EST

Presented by
Gary Bell, ASME Certified GD&T Trainer

Understanding GD&T Applications in 3DCS

via GotoWebinar
Gary Bell will be taking questions from the previous sessions of the Digital GD&T webinars, as well as additional applications of GD&T, and demonstrating the answers in 3DCS software. This webinar expands upon the previous, and both new and experienced users are sure to find it helpful. 


1. Linear Dimensioning
2. Dimensioning Hole Combinations
3. Understanding Hole Tolerances
4. Mixing GD&T and other dimensioning techniques
5. Tips for using GD&T in 3DCS

Part 2 of the Digital GD&T Webinar Series



Topics: 3DCS Creo Siemens NX Webinar CATIA V6 Tolerance Analysis 3DCS CATIA

DCS Partners with Quality Digest to Deliver Closed Loop Webinar October 25th

Quality 4.0 - How CAD GD&T Drives Model Based Definition with 3DCS Tolerance Analysis Software

DCS Partners with Quality Digest to Deliver Closed Loop Webinar October 25th

Quality 4.0 connects processes and tools, streamlining modeling creation and collaboration. See how tolerance analysis software validates and optimizes GD&T, simulating a digital twin and providing the risk of failure based on part tolerances and the assembly process. These simulations then feed downstream applications, creating SPC and manager reports and critical to quality features to direct measurement plans and manufacturing. The model continues to provide value by utilizing measured plant data to root cause production issues and testing solutions.

Topics: 3DCS Creo Siemens NX PTC Creo Webinar CATIA V6 Tolerance Analysis CATIA 3DCS

How Many Companies Are Using Embedded GD&T (CATIA FTA, NX PMI, CREO PMI) ?

How Many Companies Have Been Using Embedded GD&T in Their Process?

DCS asked its clients how often they use Embedded GD&T and if not, when are they planning on implementing Embedded GD&T

What Is Embedded GD&T?

Embedded GD&T is geometric dimensioning and tolerancing applied to a CAD model using platform specific tools and features, often presented as Functional Tolerance Annotations (FTA) in CATIA or Product Manufacturing Information (PMI) in NX and CREO. The GD&T is linked to its referencing features, so that it can be used to describe those part's tolerances, Datum features and locating properties.  It can be a powerful tool for supporting tolerance analysis

Topics: PTC Creo Siemens NX Webinar Tolerance Analysis 3DCS CATIA 3DCS Creo