Empresa CPF Parafusos, Referencia em Parafusos estojos ASTM A193 Gr. B7, B16, B8, B8m, ASTM A320 Gr. L7, Porcas ASTM A194 Gr. 2H, 4, 4L, entre outras ligas!
FreeCAD 0.15 (4671) : Sheet Metal Manual
(Manual) (日本語マニュアル)
https://www.dropbox.com/s/539nnfh9v6bb5q9/Free%20CAD%20%20Sheet%20Metal.pdf?dl=0
(Sheet metal Addon for FreeCAD)
https://theseger.com/projects/2015/06/sheet-metal-addon-for-freecad/
(FreeCAD_SheetMetal)
https://github.com/shaise/FreeCAD_SheetMetal
(Linux for an engineer)
https://linuxforanengineer.blogspot.com.es/2015/06/freecad-sheet-metal-update-2.html