FreeCAD News

The Draft Work­bench has an inter­est­ing tool called Face­binder which can be used to per­form actions like loft­ing or extrud­ing from faces rather than from sketch geom­e­try or wires. Whilst a some­what niche tool, it can be incred­i­bly use­ful when needed.

As an exam­ple we have these two parts that form the end of a wing design. They are an inter­est­ing exam­ple as they have been cre­at­ed from an import­ed .dat air­foil file which imports as a wire, so the parts have no sketch ele­ments. The wire import has then been extrud­ed on the part work­bench and then a sec­ond copy of the part has been copy past­ed. The sec­ond part has then been posi­tioned using the trans­form tool. The posi­tion it is now in forms a dihe­dral (angled) tip for a wing. We want to cre­ate a part which con­nects the two ends of the wings. As this is at an angle we can­not sim­ply length­en the extru­sions of the parts, and as there is no sketch geom­e­try, we can­not use addi­tive loft­ing tool approach­es. Sim­i­lar­ly as the parts are not cre­at­ed in Part Design and are not body items we can’t sim­ply use Shape­binders or oth­er meth­ods to loft between the faces. We could cre­ate sketch geom­e­try from the air­foil but using the Face­binder tool will be most straightforward.

If we switch to the draft work­bench we can click on the Face­Binder tool. In turn we can select the inter­nal end faces of our two wing sec­tions. This will cre­ate 2 “Face­binder” objects in the mod­el tree. 

Mov­ing to the Part work­bench we can now click on the “Loft” tool. In the loft dia­logue we can high­light the first Face­binder object in the left hand col­umn and click the right arrow to move it to the right hand col­umn, we then repeat this with the sec­ond Face­binder object. Then when we click “OK” we see that our loft­ed part is made.