TolStack app for iPhone and iPad

Put the fun back in tolerance stacks….. I know you did not expect to see the words fun and tolerance stack in the same sentence; but now with the speed and convenience of Smartphone technology, you can complete advanced tolerance stacks with ease while you’re on the go.

TolStack allows you to quickly step thru your stack dimensions, change polarity with a tap on the (+/-) button, change dimension type with a tap on the LD icon; use basic dimensions and true position allowances; enter diameters on the fly. The application will calculate the Worse Case, RSS and RMS tolerances.
The improved interface makes it convenient to run your tolerance stacks during the early design phase, this will make the final system tolerance stack a breeze; saving you time and potential design issues late in the project.

TolSTack Features:

- 10 dimensions and tolerances
- Basic dimensions with true position
- Diameters
- Worse Case, RSS and RMS
- Tolerance stack method instructions
- Decimal places 4 or 2 (inch / metric)
- 6 tolerance study samples

When you’re working with assemblies with 4 or more components, using the Root Sum of the Squares tolerance is available. You should keep in mind the required standard deviation and 6 Sigma criteria as you are assigning tolerances.
The theoretical standard deviation is calculated by dividing the tolerance by 3, once you have production parts you will want to determine the nominal values and update your stack to be sure your safety margins and functional limits are preserved.

The Decimal button is used to change the significant round off from a 2 place value to a 4 place number, this can be used for metric values.

The Tolerance Stack method is described in the information page and 6 tolerance study samples are included with-in the app.

Enter dimensions and tolerances, tap the LD symbol to change from Linear Dimension, Basic Dimension and Diameter Dimension. Using the Basic Dimension requires a True Position tolerance value. Keep in mind for a worse case study you will want to use the largest positional allowance, in an MMC stack the LMC allowances can be used. This assures the bonus tolerances are included in the stack.

Your work is important and you’ve put a lot of time into getting the design geometries right, the last step before design lock is a well thought out tolerance distribution plan…. Functional limits and safety margins are at risk if your allowances stack to a critical point.

TolStack can assist you in your tolerance distribution analysis and provide a friendly interface; you‘ll look forward to tolerance studies using TolStack.