Translations:PartDesign Bearingholder Tutorial I/42/en

From FreeCAD Documentation
Machining the top and bottom of the holder
Machining the inside of the bearing holder

Now we can cut away the material that will be machined off the raw cast part. This is very easy with the skeleton geometry defined. The idea is to create all machining features (Pockets and Grooves) using datum features only. This means they will be totally independent of the solid geometry of the bearing holder, which gives us some big advantages:

  • No matter how you change the solid geometry, the features for the machining can never fail.
  • You can create the machining geometry before finalizing the solid, which gives you useful visual feedback.
  • If you move the skeleton datum planes, then both the solid geometry and the machining will adapt automatically.
  • If you make a mistake in your solid geometry, the machining will still be in the correct position, and very likely the mistake will become glaringly obvious (e.g. a wall thickness becoming 2mm instead of 5mm). Whereas if you reference the machining to the solid geometry, it will adapt to the error in the solid and e.g. maintain the 5mm wall thickness, just in the same wrong location as the solid is.