 Mass Properties |   |
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Mass Properties | |
After selecting a part using the Single or Window Select Tool, click the Mass Properties Tool. The Mass Properties Tool allows you to check:
After you invoke the Mass Properties a dialog box will appear as below:
Volume and Mass
Volume - The volume of the part in cubic units.
Note: To change the units of the Mass Properties calculations see "Units" in the documentation for the "General Page" under "File->Settings Pages". The Units settings can be found under File->Settings, General Tab, Units pull-down.
Mass - The mass of the part in mass units. This value is based on the Material Density. Changing the Material Density will change the value of this measurement. See "Material Density" under "Settings" in this section.
Center of Mass
The Center of Mass is given in x, y, z coordinates.
Draw Center of Mass (CoM) - Click this button to draw a graphical representation of the Center of Mass. The graphic is 3 planes, the xy plane, the xz plane and the yz plane intersecting the part at the Center of Mass. If you Single Select the part and then right-click and select Hide Selection, you'll notice that there is also a precise intersection graph that represents the 3 planar intersections of the part and the CoM. You can use these intersections to check edge measurements, etc. You can also save this CoM shape out to any supported file format.
Apply "Fudge Factor" If CoM Intersection Fails - Sometimes the Center of Mass planes coincide identically with existing edges. These coincident edges are especially common with symmetrical parts and parts that were mirrored. In certain cases this coincident geometry to the intersection planes can cause the CoM intersections to fail. The "Fudge Factor" will be invoked if the intersection fails and it will allow you to slightly shift the CoM plane geometry so that the intersection will complete. If the CoM planar intersection fails the following dialog will launch:
This dialog allows you to shift the CoM geometry via global X,Y,Z translations or by rotations around X,Y,Z global axes. You can apply any combination of translations and rotations. These settings will be saved when you click OK so you don't have to re-enter information every time this dialog is launched.
Note: For reference you can turn on the global X,Y,Z axes on in TransMagic by going into the File->Settings area, select "Appearance", find the "View Settings" section and check the "View Axis" check box.
Note: If the initial CoM intersection fails you may also want to consider applying 
Full Repair to the part first. Many times the intersections fail because of precision issues at the coincident geometry. Running Full Repair on a part will virtually always increase precision in these areas and will usually allow the CoM intersections to complete without applying a Fudge Factor.
Settings
Material Density
Material - This pull-down box allows you to select various materials for your part. Changing the Material Density will change the value of the Mass measurement (weight) in the Volume and Mass section.
Density - This is the value of the currently selected Material.
Enter Custom Density - Check this box if your Material is not in the pull-down list or if you simply want to enter your own value. By checking this you will disable the Material Density pull-down and the system will default to .036 lb/in^3 which corresponds to the industry default of 1.0 gm/cm^3. You can enter your own value in this box.
Note: After entering a new Custom Density you must click the Recalculate button in order to update the Mass value calculation to the new Custom Density.
Recalculate - Click this button to update the Mass value calculation after entering a new Custom Density.
Precision
Decimal Places - Use this pull-down box to change the decimal precision in all Mass Property calculations from 2 to 6 decimal places. This value is saved in the TransMagic system settings and the next time you run a Mass Property calculation, it will calculate based on this precision.
Note: Changing the Decimal Place precision will affect processing time. If you have a very complex part and your Decimal Precision is set to 6 places, be patient as it may take a while to calculate Mass Properties at this level of precision.
Calculate Inertia Properties - Checking this box will enable the calculation of the parts Principal Axes of Inertia, Principal Moments of Inertia and Inertia Tensor.
Note: The Principal Axes of Inertia and the Principal Moments of Inertia are take at the Center of Mass.
Note: Calculating the Inertia Properties of a part will add processing time to the Mass Properties calculations.
Copy to Clipboard - Clicking this button will place all the Mass Properties of the dialog box in tabulated form to the Windows clipboard.
Note: The way TransMagic copies text data to the Windows clipboard is called Unicode and it's very nice for pasting into office documents. For example if you paste the copied data from the TransMagic Mass Properties dialog box to a Microsoft Excel spreadsheet, Excel or any other spreadsheet application will paste the data as a nicely columnized data set.
Reset Defaults - Click this button to reset the Mass Properties dialog box to it's original default settings.
OK - Click this button when you are done reviewing the Mass Properties data.