After AutoCAD what mechanical designing software is best to learn?

that depends upon which field you are working into.

If you are construction employee Auto CAD & Revit MEP , Primevera is gud.

If in Automobile sector Catia ,ANSYS,  HyperMesh.

If you are planning to move abroad , most of the company ask for Solid Works.

 LOGICIEL SOLIDWORKS

AND SAP

Definitely  Autodesk  Revit!

Try Autodesk Revit. It's good for designing purpose.

revit mep , elite for fire fighting calculatio ,and HAP for HVAC calculation

i recommend Revit MEP and after that Navisworks management 

thank you for invitationI agree with the Colleagues

Hi Again,

I recommend to you this program (SolidWorks2014 x64 Edition)

( NO NEED FOR AUTOCAD)

and it is very easy to learn.

http://www.solidworks.com/

here is the simulation of it as a mechanical.

https://www.youtube.com/watch?v=uNZmLPZHon8

Thanks for asking

SolidWorks ... Microstation ... Inventor are all good CAD programs where SolidWorks and Inventor are modeling programs and are much easier to work than CATIA

Microstation I only have worked the2 D version, however also has an excellent3D version 

Depends upon your area of activity. Autodesk has numerous specialty solutions but it pays off to try your hand at Solidworks and StudioMax first off after AutoCad.

Solid works is the best for mechanical