S T A C K U P V2.1 Copyright © Feb 1990 by William C. Bowling. All rights reserved. This program is shareware. Feel free to distribute it in its archived form with all files included and unaltered. See READ.ME for more info. The unARCed file should have all the following files included. If the file sizes don't match or if you have additional files something has been done which I didn't intend. CreateMatl 11448 ----rwed CreateMaster 18784 ----rwed Install 132 -s--rwed MasterDim 939 ----rwed StackFile 511 ----rwed CreateStack 12388 ----rwed Stackup 20064 ----rwed READ.ME 1215 ----rwed Launch 47972 ----rwed Launch.info 957 ----rwed Disk.info 3677 ----rwed MatlProps 77 ----rwed You will also have Stackup.doc which I am now writing so I couldn't very well include its size here. Can this be a paradox? Oh boy! ----------------------------------------------------- D O Y O U N E E D S T A C K U P ? This program is intended primarily for Mechanical Engineers who do a lot of design work. During the course of my career as a Liquid Fueled Rocket Engine design engineer, it became obvious to me that something like this is sorely needed. If you do not concern yourself with tolerance stackups when you design a machine then this program is not for you. The program does a loop type stack analysis. It also takes into account the thermal effects of the system. For me, this is necessary since my machines usually are doing something in a cryogenic environment while they are assembled and fabricated at ambient temperature. ----------------------------------------------------- OVERVIEW. Stackup will calculate gaps and interferences which you have identified as critical. Once the data is entered into the different files the analysis will be done by Stackup. If one of the dimensions or material types changes the program will incorporate the changes into your analyses. Just edit the appropriate data file and run the stack analysis. Results can be sent to your screen or printer. INSTALLATION. UnARC the file in a clean directory. Hard disk or floppy makes no difference. The install script file will create a directory called Files and move the sample data files into it. Just type INSTALL at the CLI prompt and you will be all set. If you launch the program from the CLI, make sure your stack is set to at least 20K. If you launch with the ICON, don't worry about a thing. The program consists of a bunch of modules. To start the program from the CLI, type RUN Launch. You MUST be located in the directory where the program is located and you MUST start the program with Launch. HOW IT WORKS. The very first thing you have to do is set up your stacks. The program will not do that for you. You need a layout of your machine where you can identify the critical gaps and interferences you want to analyze. It would be WAY beyond the scope of this document to try and teach you how to do stack analyses. I have to assume that you are at least familiar with how to do them by hand. The loop analysis used with this program adds the maximum dimension values going right and subtracts the minimum dimension values going left. It then adds the minimum dimension values going right and subtracts the maximum dimension values going left. This way, you are able to quantify the maximum and minimum gaps or interferences at the given area of interest. This requires, however, that you ALWAYS start at the left side of the gap you are interested in. When you start at the left, your sign conventions will indicate that positive values are gaps and negative values are interferences. Let's say that you have 12 areas you want to check. Each of these areas is referred to as a stack. Many of the dimensions in each stack will be common to the others. You need to number each of the dimensions you use and enter them into the Master Dimension file. Each dimension is associated with a part and it is made of some type of material. Code each of the different types of material and make the entry into the Master Dimension file. The Material Properties file will contain the temperature data for your system with respect to each of the material types. Edit this file and enter the Alpha DT associated with the material. Note that the entry is the product of the co-efficient of thermal expansion/contraction and the temperature difference. If you are colder than ambient the number you enter will be negative and vice versa if you are operating at a warmer temperature than ambient. Typically, these numbers will be in the order of magnitude of 10E-3. Now you set up your stacks. The stacks govern the relationship of the dimensions to one another. If you have laid out your stacks properly you will see that you can progress sequentially through the machine going from left to right and right to left. When you go from point A to B to C etc... the distance you travel is defined as the magnitude of a dimension and either left or right. The dimension has already been coded to correspond to those in the Master Dimension list so you enter that dimension code and the direction of travel (either L or R for left or right). The entry for left or right is case sensitive. It must be lowercase l or r. Now that you have everything defined, just run the Tolerance Study module. You will be prompted for which stack you want to compute and where you want the output sent. If something looks a little tight or loose just go to the Master Dimension list and change the dimension you want. Everything which uses that dimension will be changed accordingly. -------------------------------------------- THE MOUSE AND STACKUP. Most everything is pretty well intuitive. To edit an item in one of the modules you need to select the item number to be edited. I suggest that you use the sample data files and just load them and play with them. They are real data files which were used to size a tester I designed. The machine, by the way, works fine and has lasted a long time. The Tolerance Study module asks for keyboard input from you. This will change in future releases but, for now, that is how it works. May I be so bold as to suggest that you save your work frequently? Make sure you know the way this thing works before you get angry with it. When you are entering data into the modules you should save as you go and then load the files back. Make sure all is right with everything. Once you have a system defined with all the data files, back them up (make copies of the datafiles). This program works with the specifically named files and doesn't care of you have already defined one set of master dimensions when you are ready for the next machine. I suggest that you do a LOAD from the modules to see if files you want are already there. If they are, and you write a new file, you will lose the old work. ----------------------------------------------------------- I would appreciate any comments you have about this software. If you find something which isn't right (bugs) PLEASE let me know. This thing isn't foolproof but then how many Mechanical Design Engineers do you know who are fools?