i am a drafting studend and recently got auto cad mechanical 2010  i need to know how to save my drawings as older versions of autocad so my master cam x3 can read them thanks for any help 

Hi hazetroy,
When you save an AutoCAD file, at the bottom of the save screen it will say what you are saving the file as (AutoCAD 2007) for example. Just click on the arrow on the right side and it will bring up a list of different file types and versions you can save your file as. Select the one you want and that should do it.
I hope that helps,
nameci

If you are saving for older version of Mechanical (not plain AutoCAD), make sure you use the "mechanical" format - see the tip:
http://www.cadforum.cz/cadforum_en/qaID.asp?tip=5982