3D STEP to VRML

Has anyone any suggestions on converting 3D STEP to VRML? Or for simplifying the VRML file?Diptrace uses VRML for 3D models. I can get the smaller example BGA's from the library to work by opening them in FreeCAD and saving as VRML. The resultant VRML files are quite large. For example with the BGA27C100P3X9_300X900X130N the size of step file is 116KB and the VRML file is 10,123KB.This works for BGA4C40P2X2_76X76X50N and BGA27C100P3X9_300X900X130 but not BGA64C80P8X8_800X800X140 or BGA169C100P13X13_1400X1400X155. Diptrace does not import the last two and gives no errors.I can't check the VRML output with FreeCAD, as it will only read back in the VRML file for the BGA4C40P2X2_76X76X50N, it just crashes it I try to read in any of the other three.

At the moment I either grab a 3D model from the manufacturers website or use FreeCAD to knock up something.  I have been meaning to look at the STEP output from FPX but your comment "the generated STEP 3D files can get fairly large, especially the ones with filleted corners and what not" raises a red flag.

Pulsonix works with both IDF and STEP files.  It works with STEP files by importing a STEP file for a PCB that has been output from an MCAD program, or exporting a STEP file of board and components.  Pulsonix will either use an existing STEP file for a component or create one based on the component type and if you've specified anything in the Pulsonix 3D viewer.

If you have an existing STEP model you can place it in a folder, then in the footprint in the Pulsonix library (or the part) place three attributes to point to the STEP file filename, X/Y/Z rotation, and X/Y/Z offset.

The biggest hassle when dealing with STEP files downloaded from manufacturers is the X/Y/Z rotations and offsets which appear to be random and vary between parts, including parts from the same manufacturers.

To be honest we found the more elaberate manufacturer-supplied STEP files and Pulsonix generated STEP models for components to be a hassle for our MCAD Engineers when they imported into Solidworks since Pulsonix was creating a fancy component body with bended legs and terminals on chip components.  They've told me that this is a hassle for them to deal with, increasing complexity and file size unnecessarily.

They are only interested in a simple space model - they don't want or need fancy chamfers on IC bodies that take up file space in the STEP file and when processing the models in Solidworks.

With that in mind I began using FreeCAD recently to create some simple STEP models.  All we need for a chip component is a single cube of the maximum size, whilst all we need for something like a SOP chip is a cube for the body and a couple of cubes for the two rows of legs, and for SOT-23s, a cube for the body and a cube for each leg.

See these examples:

Chip CAP:



SOT-23



SOP or SOIC



I've not got around to asking for a demo of the sTEP from FPX yet but if you're putting the jazzy bits in then I'd probably not be interested in it.

A choice might be useful between a simple block STEP file or a whistles-and-bells STEP file.

It's the "High Quality" label that might be an issue.  It's not me that needs to be persueded when it comes to STEP models from FPX - it's the Mechanical CAD Engineers here using Solidworks.

Here we have two of them (they're nice chaps really, even when they're making the PCB profiles smaller!).  We use Solidworks and they are the ones that are saying that the elaborate STEP models with the modeled terminals are not suitable for what they want.  They have to do extra work on them.

I come from an Electronics background and have only just started to "play" with FreeCAD so I'm not totally familiar with how they are taking and using this data but the feedback they've been giving me is that the simple cube shapes are a lot easier and quicker for them to work with in Solidworks.

Before purchasing the upgrade I had a go at the trial license which is still installed.  It allows only output of BGA STEP files though, and as you say, these can be the larger ones.  I doubt they'd be a good example to show the MCAD guys to convince them.
 
All they are after is a simple space model to check for mechanical fit.  They aren't interested in "nice" graphics, nor interested in the component legs being correct.

This is exactly why we have intro pricing now - won't last for long.