Clamping Support (PartDesign, SheetMetal & TechDraw)

This tutorial explains how to model a clamping support for pole mount antenna in FreeCAD 0.19. Through this example, we will see how to design a basic sheet metal product with PartDesign and SheetMetal Worbenches (WB). Then how to made a drawing of unfolded sheet metal with TechDraw WB.

  1. Step 1: Install SheetMetal WB (optional)

    (optional - if you have not yet installed SheetMetal WB)

    1) Go to -> Tools,

    2) -> Addon Manager,

    3) Select sheetmetal from the drop-down list,

    4) Click on Install/Update.

  2. Step 2: Made a first extrusion

    1) Go to Part Design WB ;

    2) Create a new Sketch on XY plane in Part Design ;

    3) In Sketcher WB, reproduce the sketch below : first, use Rectangle and Slot functions to made the shape, then add constraint ;

    NB : To add a cotation between the two arches of a Slot you can use construction lines tangent to the arches.

    4) Extrud a solid form the created sketch with Pad function ;

    5) Sheet metal thickness is 2 mm as showed below.

  3. Step 3: Add Bends

    1) Go to Sheet Metal WB ;

    2) Select a edge of the previously created Pad and create a bend with Make Wall function ;

    3) Set parameters :

    • angle to 90,00°,
    • Bend Type to "Material Inside"
    • lenght to 17,00 mm.

    4) Select the opposite edge and made same bend with same parameters.

  4. Step 4: Draw Pocket shape

    1) Create a new sketch on XZ plane ;

    2) Reproduce the sketch : below at the side of the part,

    3) Then on the inside of the part.

  5. Step 5: Add symetrical Pockets through the two bends

    1) Leave Sketcher and make a Pocket with step 4 sketch ;

    2) Type is Through all, in order to reach the two bends.

    3) Use Mirrored function to add symetrical pockets ;

    4) Mirror must be executed on the YZ plane.

  6. Step 6: Add Fillets (optional)

    1) For more realism, you can add round edges with the Fillet function ;

    2) Fillet can be set at 0.30 mm on all protruding angles.

  7. Step 7: Flatten Sheet Metal

    1) Once the part is finished, we will be able to unfold it by returning to the Sheet Metal WB ;

    2) Select the base plane of part and click on Unfold function ;

    3) You have to chose a K-factor before cliking on OK. Here ANSI.

    It will generate a solid and a sketch as below, that correspond to unfolded sheet metal.

    This will allow to insert an unfolded view of sheet metal with TechDraw WB :

    4) Create a new Page ;

    5) Select a face of Unfold body ;

    6) Use Insert View function.

  8. Step 8: Drawing Example

    Below you can find an example of drawing for the Clamping Support with TechDraw default template.

    1) Functions used to insert views : Insert View - to add five views of the part ; Insert Detail View - to insert detail A ;

    2) Functions used to place dimmensions : New Horizontal ; New Vertical ; New Radius ; New Angle ;

    3) Functions used to add annotation : Insert Annotation ; Add Centerline to Face - to made symmetry lines ; Add a cosmetic line - to add bending line.