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quelques tips : le rectangle dessiné dans le sketch "Mapped_Sketch" est une représentation de la zone, ses dimensions peuvent être modifiées, Map on sketch fera en sorte que tout ce qu'il y a dans le rectangle soit mappé de façon proportionnelle sur la surface donc là en le décrochant de l'origine, et en décalant un peu le coin bas/gauche et haut/droit les perçages ne débordent plus de la surface dans les propriétés de Sketch on surface "Fill Face" ce qui permet de... remplir les faces et donc de pouvoir faire une opération booléenne standard sans faire un slice j'ai ensuite fait un Clone de la pièce pour faire l'autre coté que j'ai retourné et positionné "au pif" et pour éviter des chevauchements disgracieux, au lieu de faire une opération booléenne de type "Fuse", j'ai utilisé la fonction Connect qui normalement sert pour connecter des tubes le fichier était trop volumineux, alors j'ai viré le cut, le clone et la fonction connect mais il reste la grille avec des bords pleins et le sketch on surface avec les "trous pleins" : grilleEssai_2 fth.FCStd

How many times should it be repeated?

There is the dogbone dress up for profile and inner corners. CAM Array can do it.

see where it goes wrong: By "it" do you mean your workflow? I don't think I've ever taken 3 hours from sketch to gcode in CAM workbench.

I have been in a chat on ChatGPT regarding defining an arc corner surface in Python, which seems to still be an issue in FreeCAD CAM. Based on my limited understanding on what is needed, ChatGPT created a parametric Python script. These are the requirements I provided (which are probably incomplete): 1st input I am working within a cartesian (XYZ) workspace. I have a 90 degree arc with a radius of 3/4" (19.05mm) on the XY plane centered at 100, 100, 30 from 0 degrees to 90 degrees. I need to convert the arc to equal segments with a max length of 0.1". How would you script this process in Python 3? 2nd input From the same center point, I need a series of 90 degree reference arcs running vertically using the segment end points as the top points and arcing downward. Along the Z axis at 0.1" increments, a new horizontal arc needs to be created that passes through all of the reference arcs. Each interation needs to be converted to segments along the new horizontal arc. I don't have enough experience (yet) to try to implement a solution in FreeCAD CAM. Hopefully, there is something useful in the attached script... Parametric 3D Arc Surface G-code Generator.py

Thanks all for the quick replies, I'm glad to see I'm on the right track! I'll just figure out which pass to do first. @MattTheNoob fair point about the corners, I'd been deferring that, but I know I can clean them up with a hand file, or maybe change tools and do a final pass with a 1mm or something. This is a onetime cut, so I don't have to worry about efficiency too much. I may be able to just leave them also. BUT, speaking of "onetime"; if I were to make 4 of these holes on the same run, is there any way to parameterize the location of the hole and re-run the same 2 operations on each hole, without duplicating the operations 4 times? -John

The Mirror tool in Part Design acts on features (typically the last in the Body). The Part workbench Mirror tool mirrors the Body (technically, the solid represented by the Body) and creates a new solid. You should not select features (Pad/Pocket/etc.) of a Body when using this tool. Neither effects the sketches involved.

Aside from the CAM strategy, you arent going to get square inside corners on a mill.

If I compare the FreeCAD workflow vs my ESTLcam workflow, I can see where it goes wrong: https://wiki.freecad.org/CAM_Vcarve Half of the manuals is preparing the svg file. While in ESTLcam I just import and start selecting the closed boundries. And if I am really lazy I can even imprt a black and white png and just let ESTLcam take care of it. It's kinda scary but I tried it once it and worked pretty good. And off-course it is not optimized but I rather have the machine running 3 hours longer then I have to be fiddling with my CAM program for 3 hours to save 3 hours of run-time. (I often only do carvings once) This is the whole issue with FreeCAD, everyone is so focused on the code, but so many devs don't care about the real world practicality.

You should use more refinement volumes. In the outer regions you dont need a fine mesh, the flow field is nearly constant. In this case I used 2 refinement volumes and 1 surface refinement. It is an older model, done with FC1.0.2. Maybe it does not run on your machine. But you get the idea. BR_66_CFD_RC.FCStd

Prior to came here I have used another CAM CamBam, this was very simple, you draw a 2d shape, the select the closed wires and select if they are a profile or a pocker, then set the starting Z and the Ending Z (or a Depth), stepover and such things, and then generate the GCODE. I would think as a minimum addition to that you would need the ability to leave islands holding the stock or on the final pass much unhappiness will result.

How about: Please read the whole topic.