Trouble on place 3d shapes

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I found some wrl modules at grabcad.com. I scale those wrl files using meshlab to fit my PCB. But some wrl module is so complex to adjust position, like below picture showed. if anyway easy to solved this? Or any suggested software?

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Check out:

Also, if you use the development branch you can use STEP/IGES models instead and forget about VRML. However, if you want things to look pretty, VRML is still the best option.

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I did download some step/iges modules, but I don’t know how to use. So i convert a wrl from stl module to use in kicad.

Does WRL file is not more advanced than the others, STEP/IGES?
Does any 3d file format support pin define? I think this is an advanced function. If can define pins, the module can automatic rotate and scale to fit in PCB.

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STEP is a mechanical format for 3d models … so it is the best to be used for kicad… Kicad 4 supports only VRML, then the best option is to get a STEP model and convert it to VRML.
The easiest road is to use kicad StepUp
You can load the step model and kicad footprint in FreeCAD and then align the model to the footprint. After that just export your aligned models with the export button and move your models to the right folder on your library

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To answer this one, no.
MCAD is not ‘aware’ of ‘ECAD’ (yet) and probably wont be for the next 10 years at least (never say never).
The information link that you ‘want’ is just not there.

KiCAD (and with that I really mean the librarians and people behind better MCAD support in KiCAD - say hello to them here) are already working on getting most of the 3D shapes created parametric in FreeCAD to fit out-of-the-box with the footprints in KiCAD (footprints affected by this are also being created via scripts).
So even if there is no ‘awareness’ of STEP models and footprints of each other, the people who create them ‘are that link’ and work on getting this right.

For any other case (were a user of KiCAD needs something out-of-order) you have to do it yourself unfortunately - especially when it involves 3rd party 3D shapes supplied by a manufacturer.

PS: STEP models have ‘scale’ built in (actually it defines proper units like 1 unit in the file correspond to 1 mm for example), VRML doesn’t - it just ‘knows’ units. That’s why there is a scale value in KiCAD at all. It is not needed for proper MCAD models really, but VRML needs it.
Orientation and position is a matter of origin and which plane the MCAD modeller used as basis… KiCAD expects the XY plane to be the basis and the z axis sitting perpendicular on the pcb. MCAD programs don’t force that (nor is there a common ground), so every operator is free to chose…

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Do you mean something like constrains? The feature where you can tell the mcad software that two parts are positioned relative to each other in a special way?
Example: In most mcad systems there is an assembly workbench where you can “bolt” together multiple parts by defining coincidence, contact, coaxial, angle or distance constrains. (not an exhaustive list. I’m sure there are more possible constrains)

I think aligning 3d models to footprints is best done outside of kicad in the software where you design the 3d model. Example in freecad by using kicad stepup and maybe the assembly2 workbench for constraining the part. (or use the tools provided by kicad stepup itself as @maui already suggested.)

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It’s interesting to let FreeCAD do the right thing. thanks. I will try it later.

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Thanks all. I am not skill at CAD mechanism. Just a guess, please don’t care.

My means is as you see the wrl file is just a text file with structure defined inside. Maybe we can add one structure like this. File save as wrl or kicad_wrl.

Hotspot {
    XYpoint
          [ -4.05892 -1.6764, -6.05892 -1.6764, -8.05892 -1.6764]
}

Here we defined 3 points (omitted Z axis, Z=0), or say hotspot in a line. That’s 3 pins axis position.

The other standard software will ignore this segment. But kicad can understand, automatic rotate and scale it, let 3 points fit into 3 pins of component.

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but if you need to add something (which is just not a standard around) to the WRL file,is it not simple easier fill the footprint module with these values? or better just align correctly the model to footprint and save it?
But in general I would suggest not to download WRL files, get instead STEP model which is normally scaled 1:1 in mm
After that align the STEP to your footprint in kicad (dev release) or in freecad, align it and export it 1:1 STEP and 1/2.54 WRL scaled … the FC solution works both for kicad dev and stable

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