Notes on 3D footprints

Misc. notes on 3D footprints:

  • One “Wings unit” in Wings 3D equals 0.1 inch in PCBNew. (I was expecting metric, but no.)

  • In Wings, the Y axis is “up”, while in PCBNew, the Z axis is “up”.

  • When you change the 3D model of a footprint, PCBnew won’t display it until you reload the footprints. See “Reloading Footprints in PCBNew” for the very obscure location of the dialog button which does this. (Hint to developers: in pro tools such as Autodesk Inventor, there’s an icon that lights up when you’re in some out-of-sync condition. Clicking on it tells you what’s out of sync. This would be a good way to handle KiCAD’s many out-of-sync conditions.)

  • Without Internet connectivity, you can’t edit footprints. The footprint editor will stall trying to reach Github.

The .1 inch is historic - then again VRML is also historic. The Z axis = up is common for ECAD/MCAD - in the case of ECAD the x,y coordinates are the locations of features so of course z is the vertical dimension.

You can edit the instance (local copy) of a footprint or you can edit the copy in the library collection. If you edit the instance then you see the result right away. If you edit the library copy then you have to tell pcbnew to replace its instances with a fresh copy from the library.

You can always remove all the github stuff; just edit the per-user fp-lib-table file and remove all references to github. I never use git hub so I never have these github problems that people complain about.

That 1 unit in wings = 0.1 inch in KiCAD is KiCAD’s ‘fault’.
On the other hand VRML doesn’t know units for dimensions, so really anybody can interpret it as they want.
STEP (which is what KiCAD will be using in the future) comes with unit’s, so no more dis ambiguity there :heart_eyes:

You’re right about the sync button. In KiCAD the ‘read-netlist’ dialog essentially does the update part, but there never is information if stuff is different from the libs (except for EEschema if your projects symbols differ from the libraries you use at startup you get told).

As for the github thing - I’m with @cbernardo on this one :wink:

STEP import would be nice, if it works. KiCAD’s VRML import is very limited. Mostly, only stuff from Wings 3D works, although I had a successful import of a VRML model of a CUI 2.5mm jack from the vendor. (It’s sized wrong, being metric, but that can be worked around.)

The 3D renderer in KiCAD is quite nice when you provide all the 3D models.

Being tied to Wings is a big limitation. Wings has such a limited and useless set of import filters that it’s hard to get any existing model in. It can import STL, but that’s a raw mesh; you lose any colors. Wings’ 3D Studio import crashes on most modern 3D Studio files. I look forward to STEP import.

Hi,

Step 3D models ARE supported by Kicad with cbernardo plugin.

Hi,

  1. if you are using kicad stable 4 you may need to try kicad StepUp tools to convert STEP 3D models to VRML and then have your models in kicad; then again with kicad StepUp you can convert your kicad board to STEP for having a 3D mechanical model of your artwork
  2. if you are using developer release you can directly manage STEP models inside kicad through the OCE plugin; to align models to footprint you can still use kicad StepUp tools or just the kicad 3D interface adding offest and rotation as required; to export your board and parts you may use again kicad StepUp tools (the tools can handle VRML, STEP or IGES in a mixed way and have many options to export) or just the internal kicad menu to export STEP model.

Wings3D (or any other mesh modeler) should not be used as a 3d modeler if you are planning to have an ECAD MCAD collaboration
FreeCAD is a robust and open source solution for this kind of collaboration and may would be useful to substitute FreeCAD to Wings3D in the kicad installation package suggestion :smiley:
Maurice

a quick search in this forum for STEP would have you pointed to these options
https://forum.kicad.info/search?q=STEP

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