So i've recently noticed that some of the material is OFF in the Solidworks material calculations. HOW can i make a new material code so that the calculations are CORRECT. Its only off very little but this is critical for the work i'm doing. THANKS for the help guys.
Open up your material property dialogue box in the history manager.
Down at the bottom of the list there should be (user name) materials or "Custom Materials"
Make a (right click) Create "New Category" in the Custom Materials file
Right click on the new category file
Create New Material
That should allow you to enter everything you need. This is the same for as long as I can remember.