About Geometric Stackup

Geometric Stackup is an application from HCL Technologies Ltd that performs tolerance stackup analysis on all major CAD files. It’s a multi-CAD platform for performing tolerance stackup analysis on either a part or assembly. This application helps design engineer perform dimensional tolerance stackup analysis quickly in a seam-less manner in a very intuitive and user-friendly environment.

Need for Tolerance Stackup Analysis

What is Tolerance Stackup analysis?

Stackup analysis is done to find out the minimum and maximum distance between two datums.
  • It is not possible to manufacture the parts with precise dimensions. This creates dimensional variations in the manufactured parts
  • These variations are additive. They can cause problems at the time of assembling. Either the parts may not fit into the assembly or there could be functionality issues
  • This results in wastage of material, quality issues and cost overheads
  • It is therefore necessary to be able to predict what percentage of parts will assemble properly. These predictions are made using tolerance stackup analysis
  • Design problems can also be addressed by using stackup analysis at an early stage

System Requirements

  • Operating Systems (32 & 64 bit) – Windows 7, Windows 8, Windows 8.1 and Windows 10
  • Monitor – 1280 X 1024 or higher resolution with support for 32-bit color
  • RAM – 4GB or more recommended
  • Internet Explorer version 9.0 and above
  • Microsoft Excel 2007 and above
  • Graphics Hardware supporting OpenGL 1.4 and above
  • Supported CAD Formats

    Geometric Stackup supports CATIA V5, NX, I-DEAS, Pro/ENGINEER, Creo Parametric, SOLIDWORKS, Inventor, SolidEdge, 2D file formats like DWG & DXF and neutrals like STEP/STP, IGES/IGS, and Parasolid

How it works?


Open the part

Open a part / assembly for performing tolerance stackup analysis. Geometric Stackup has standard view functionality with 7 present view modes and supports standard & wireframe rendering for part models.

Define the gap

We indicate the gap for tolerance analysis. This gap is defined by selecting the 2 entities. As shown in the above image, 2 faces are selected to define the gap. This gap is shown with the help of a green dimension line.

Chain Creation

Select the components in sequence. Define dimensions between the components to complete the loop. In the above image, black dimension lines indicate the sequence in which components are selected.

Results Analysis

You can generate your tolerance stackup analysis reports in XML and spreadsheet formats which can be easily shared with internal teams and external suppliers, vendors

Result Analysis

Interactive Results

The Input Dimensions Window indicates the dimensions selected by the user. User can modify the tolerance values, add assembly shift and GD&T or delete a dimension if required for further analysis. Use the icon in the dimension table if you want to delete a particular dimension.

Supports GD&T

The GD&T Window appears when user clicks on any row of GD&T column. It allows user to add applicable geometric tolerance on selected entity. Use the icon or "Delete" key to delete the selected GD&T value and the icon or key "Enter" to add GD&T value. To update any existing GD&T value, select the required row and use the icon or "Enter" key to update the value.

Supports Assembly Shift

The Assembly Shift Window appears when user clicks on a row of ASMShift column. It allows user to add assembly shift tolerance. Use the icon or "Enter" key to add the ASMShift value.

Supports Assembly Shift

To add assembly shift for non-fastener features, different window will appear by automatically detecting features other than fasteners.User may add 'Min Shift' and 'Max Shift' values respectively.

Supports Worst Case & RSS Methods

The Results Window provides the results for worst case and RSS analysis. RSS results are available upto 6 sigma variation. User can specify the specification limits by using the upper and lower limit text boxes. Yeild indicates the percentage of parts that can be manufactured for the given tolerance limits.

Interactive Charts

Distribution Chart

The Distribution Chart indicates the distribution of parts that are manufactured with the given manufacturing tolerance limits. The central yellow line on the bell curve indicates the nominal value around which most of the parts will be manufactured. The green area indicates the total yeild. The orange line indicates the lower limit meaning that the parts manufactured below this limit are considered as scrap. Red area under the bell curve indicates the scrap amount. The blue line indicates upper limit meaning that the parts manufactured above this limit can possibly be reworked to achieve success. The sky blue area indicates the rework amount.

Contribution Chart

The Contribution Chart gives an idea about how the dimensions are contributing to the gap that is being analyzed. The manufacturing tolerance for the gap under analysis can be adjusted by knowing which is the maximum contributing dimension. For e.g in the contribution chart shown in the image, Dim5 is the maximum contributing dimension. User can change the tolerance for this dimension to achieve the desired manufacturing tolerance limit for the gap under analysis. To change the nominal value for a component, user will need to update the model in native CAD.