Welcome to my third, and I promise last, article in this series on using TolAnalyst for assemblies. In this final article, I’m running the study that I’ve set up to see the results, and adjusting them as necessary. Again, before going any further, if you haven’t done so already, please read Part 1 and Part 2 of this series. Once you run the study, you get the Analysis Results, including the Analysis Summary, relaying the nominal, Min, Max, Root Sum Square Min and Max. It’s useful that SOLIDWORKS gives us the nominal measurement again of 0.1”, but there is a problem with the Min and Max values.
Keep in mind, these blades need to not crash, and not be further than ¼” in order to cut. The Min value is -0.091”, which is a negative number! Negative means that the blades will bind. On top of that, the Max value is showing 0.321”, which is higher than 0.25”. Luckily though, under that summary, there is the Analysis Data and Display. This summarizes the contributors to those numbers and the percentage of their contribution. This can be set to MAX or MIN depending on what you’re interested in.
Looking at this display, Hole Pattern4 in the Lower Knife Block is the biggest contributor, coming in at 54.61%. Clicking on Hole Pattern4 in this bocks pulls up both the Position and Dimension DimXpert information. You can select either by clicking just that in the Analysis Data and Display.
Looking at the feature control frame, the circular tolerance is set to 0.2”, which is pretty loose. Double click on that to change it, and lower it to .04”. It’s really handy to be able to access and change the tolerances right here in the middle of an analysis. Hit the Recalculate button to see how the change affects the assembly.
The results are closer, but still not quite in the Min/Max range that the design parameters call for, so it’s time to look at the next contributor, which is Hole Pattern1 in the Upper Knife Block at 49.6%.
Again, clicking on it gives access to the tolerance information, and the positional tolerance is a too loose at 0.1”.
You can save this analysis and use it later if the design changes by hitting the green check at the top of the Property Manager. If you click the Export Results button, the results can be saved to an Excel, XML or HTML format to share with others. Now that the tolerances have been established, as long as the parts are made within the specifications, they will fit together. That wraps up this series, I hope you enjoyed it. If you prefer, you can see my YouTube video here. Thanks for reading!