Occasionally, we get requests from users looking to stack their dimensions. This can happen when you have multiple dimensions with the same tolerances and would like to run a chart on all the dimensions together rather than separately. The term comes from the fact that you are literally taking the separate columns, stacking them into one large column, and then running the report on that new column.
For example, let's say you are drilling 3 holes and all are 1 inch +/- .005 in. So far, you've measured 100 parts. If you look at them in the Edit Data (spreadsheet) view of QC-CALC SPC, you'll see them as three separate columns of data each with 100 rows of measurements. Stacking them would make them one large column of 300 rows. You can then run the report on these rows as if they were one dimension.
Steps
- In QC-CALC SPC, choose a report to run (i.e. Report > XBar and Range).
- In the Dimension Selector screen, choose the dimensions you would like to group/stack.
- At the bottom of the screen, check the Group Dimensions box.
- Click OK to run your report.
- QC-CALC will automatically group/stack your dimensions and run one report.
More Information
This functionality works for both normal QCC files as well as grouped QCC files. If you are measuring half your features on a CMM and the other half on a handheld gage, you can create a group of the two QCC files and group/stack the dimensions across both.
NOTE: Grouping Dimensions in QC-CALC SPC does NOT validate that the tolerances are the same. Instead, it always uses the first dimension's nominal and tolerances. Therefore, you may get unexpected results if you group/stack 3 dimensions with very different nominals.