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# Read me stack up copy

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Excel Stack Up form instructions

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### Read me stack up copy

2. 2. Converting unequal bilateral tolerances to an equal bilateral tolerance: Enter dimensions with an equal bilateral tolerance, i.e. 63.465 ±0.165 not 63.5 +0.13 / -0.2, as in the case of a Ring Gear mounting distance. Enter 25.4 MIN as 25.4 ± .0.0. Enter 25.4 MAX as 25.4 ± .0.0. Limits dimensions: Enter Max and Min limits in the Max and Min columns just as they appear on the drawing. Use this formula in the Dim. Column cell =(Link to Max value+link to Min value)/2 to derive the mean . Use this formula in the Tol. column cell =Link to Dim value-Link to Min value to derive the tolerance. Use Excel to calculate the Dim and Tol. values instead of a hand calculator. Max or Min only dimensions 14.7 Min Full Thread, Enter 14.7000±0.0000 not 7.5000±7.5000 because it can be more 14.7 but is not defined. 0.5 Max chamfer. Enter 0.2500±0.2500 or 0.5000±0.0000 because 0.0000 is the minimum. Thread tables, Spline Summaries and USS Steel gage dimensions are usually limits dimensions and some are Max or Min only dimensions. Check the standard or spec. and enter accordingly. Reference dimensions A reference dimension on a upper level drawing means the tolerance is controlled on a lower level drawing and the sum shown may involve several dimensions. Do not enter the reference dimension with no tolerance or use the title lock tolerance. A good example is the CL of Pinion to Cl of Diff dimension on a Axle Assy. The (12.7) and ±0.25 title block tolerance does not locate the Differential. The Ring Gear Mtg. distance and Diff Case flange to Shaft hole Basic dimension and associated Postional tolerance does. Bracketed Dimensions Usually on an upper level drawing and are provided for customer or manufacturing knowledge only and are controlled on a lower level drawings or indicate an alternate method of manufacture. An example is the second referenced Axle Assy press up limits dimension samples uses when they can not press both tubes into a carrier at the same time in the lab like the assembly plant does. Use the lower level dimensions and primary manufacturing process unless otherwise specified. BASIC dimensions Basic dimensions have no tolerance. The tolerance is the GDT value with the feature the Basic dimension locates. In the Input list identify the location description as Basic. Enter the dimension in the Dim. Column and enter 0.0000 in the Tol. column. Such as: 95.5000±0.0000 GDT - Form Tolerances - Straightness, Flatness, Circularity, Cylindricity Usually not used in axial stacks. Rules for Flatness when “Thru” or “To” features are quite detailed as to when they do apply. Others sometime used in radial Stacks. Consult Stack Up manual Jason Stanley has in library for examples. GDT - Profile tolerances - Profile Of A Line, Profile Of A Surface Enter the Basic dimension as described above. In the next row identify the feature and GDT tolerance such as: COVER – FIN Inner bowl offset (1/2 1.5 Profile. Tol.). Next to it in the Dim column enter 0.0000. In the Tol. Column enter 0.7500. GDT - Orientation tolerances – Angularity, Perpendicularity, Parallelism Usually not used in axial stacks when mating surfaces are of equal size. Tec-ease, Inc. sells an excellent self instruction workbook that discusses the creation of Orientation Stack ups called GEOMETRIC TOLERANCING – STACKS and ANALYSIS WORKBOOK for \$46.00. Jason Stanley has purchased copy for the library. See this for examples. Charlie Roscoe has a personal copy. Created by Charles S. Roscoe Revised: 02/08/2010 2 of 21 Printed: 10/13/2013 22:46 A10/P10
5. 5. TO DELETE A ROW IN THE VARIABLE LIST OR IN A STACK UP BOX Click on the Row heading number of the row you want to delete. Select “Edit” and “Delete” off the tool bar. Use Edit Find to find every instance of that row by key word or dimension. TO SEARCH FOR ORIGINS OR USES OF LINKED DATA USING EDIT FIND You can find where A dimension or tolerance is used elsewhere by using Edit Find in the tool bar at he top. Type “XX.XX - (any value)” in the box at top. Select “by rows” in the “Search” box. Select “Values” not “Formulas” from the “Look in” box. Pick “Find next” and the cursor will jump to the next cell where that “XX.XX” is used. Keep picking it and it will cycle through the spreadsheet top to bottom and back again to the top where you started. If different parts have the same value it will find those as well. Created by Charles S. Roscoe Revised: 02/08/2010 5 of 21 Printed: 10/13/2013 22:46 A10/P10
7. 7. Stack 1 Row not linked to Stack 3. No Audit arrows appeared. Stack 1 “± sign ” linked incorrectly to another dimension in the list, not Stack 3. In Stack 1 - The range of cells included in the Statistical Tol. formula in cell G74 DOES NOT include the 0.4000 tolerance in cell G70. Note that the blue Audit boundary box does not include the 0.4000 value. Results will update automatically when it is corrected………….as shown at right. USING CONTROL F Select keys Ctrl and F and the following dialog box will open allowing you to search for specific text or a value. Use the Replace button if you want to replace text in multiple places with something else. Four corrections were done below in example this way. Change Look in: to Values using drop down arrow at right if looking for a number. Created by Charles S. Roscoe Revised: 02/08/2010 7 of 21 Printed: 10/13/2013 22:46 A10/P10