Comparison of EZtol vs. Using Spreadsheets


Manual or Spreadsheet Analysis


Accuracy –
Formula Derivation
User must manually define loop and dimension nominals Stack up loop automatically created from assembly model
Type of Analysis Typically just worst-case or RSS Supports worst-case, RSS, and generalized statistical results
Standardized Method Can be modified.
Can have multiple appearances
Consistent – all analyses use same format, same mathematics
Identification of optimum dimensioning scheme None Stack up definition starts with the optimum dimensioning scheme
Assembly shift between parts having clearance Must be manually calculated Automatically included
Manage Multiple Stack ups Each is typically independent unless much effort is made to tie the stack ups together Automatically manages the fact that a dimension can contribute to more than one stack up
Geometric Tolerances Requires user expertise in the standard and how to calculate both worst-case and statistically Logic for proper treatment embedded into the program – user not required to have deep understanding of standards
Warning that the problem may not be 1D None Yes
Report Generation User must prepare and capture desired image from CAD models “Snapshot” automatically captures image to include in reports
Visualized Closed Loop Manually added to the captured image or shown prior to image capture Always presented when working on a stack up and included in snapshot
Easy Identification of Top Contributors Not usually included Automatic
Quality Dashboard Manually included if at all Summary table shows results of each stack up along with a roll-up quality summary