TurboCAD has for the past several versions, included powerful 3D Modification tools which are ideally suited to sheet metal design.
CAD Workflow Integration Between the Office and the Field
Val Carter Reviews TurboCAD Pro Platinum 2017
A quick tip on altering the orthogonal snap.
A short introduction on the benefits of using "by layer"
Brian gives a some advice on scale factors in TurboCAD
Paul start us down the path to the adventure of 3D
Drop YouTube by and take a look at a new video tutorial series by Don Cheke, one of TurboCAD's top power users.
PaulTheCAD gives us the basics of printing.
An introduction to Layers