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The positive and the negative: The positive: Using the concept "Sketch-on-face" I think is the best way to create models. This macro allows you to use FreeCAD and design using sketch-on-face without having a topolocical naming problem (TNP) when designing a model.

The negative: The macro can give you some stability adding/moving features during design. Once you get to the point of adding fillets or drawings (TechDraw) you can't add any more edges to the early model, you can still add stuff, just don't edit something previously created. Because of TNP the vertex and lines will continue to get renumbered. This means that some very important parts of FreeCAD can't be used reliably like Datum objects, external geometry. Most users can work around many things but TechDraw is very important and the drawings will get messed up if new edges are added to a model on a previously generated feature. For instance you can create a new sketch on a face and make a hole anywhere, this is of coarse adding new edges to the end of the model, not to a previous feature.

Instructions.

First thing, while in Sketcher don't use the "Auto update" option in the Combo view panel, it can cause a TNP event just by adding one extra edge. Instead we will be using the bottom button of the dialog "Update Model".

In the first few lines of the macro there is a global "widget width", increase it if you need to for your style sheet. I have made changes to try and get many style sheets to work but I do like No sytle sheet the best.

Limitataions: This macro uses placements to process models, it cares little about edges or vertex. This means that external geo. and fillets can be a problem. We can do without external geo. but fillets are required often times, do them last and expect to recreate them if you edit an early sketch because the edges that are filleted will change and can also cause an error. There are many ways to model-in a fillet instead of using the fillet tool, because the macro stabilizes and stops the(topological naming issue) on faces we can use Sketch on-face Pocketing to make many fillets.

How to use it: Start the macro, create sketches and then features using "Sketch on face" modeling. When a sketch is closed you will see the dialog process for a short time (see the two bottom buttons), wait for it to finish. There really isn't anything you need to do other than model. Once you get to a point you can go back and edit the first sketch (any early sketch) and add a hole (or any shape) or dozens of holes. Close the sketch. No TNP!

While in sketch edit mode you can add something like a hole for instance, you can then click the dialog "Update model" button, this will process the model immediately so you can see your changes, an update will also occur automatically when exiting sketcher so you only need to click the manual update if you want to see the changes made right now.

If you get an error then click "Undo" and then "Update model" until you get to a "Model OK!"