Dealing with Incorrect STEP Linear Unit Scale

• Back to VTube-STEP or VTube-LASER

How Wrong Scales in STEP Files Affect VTube

After an import of a STEP model of a tube. if you attempt to calculate a centerline and find that the calculation takes much longer than usual, and the resulting values are extremely large, then there is probably a problem in the original STEP file setup.

For example, this STEP file imported the following values:

The import required 28,539 loops which is much higher than normal.

How to Fix the STEP File in a Text Editor

Open the STEP file in a text editor and search for SI_UNIT.

In the import shown above the line with LENGTH_UNIT shows this:

#815=(LENGTH_UNIT()NAMED_UNIT(*)SI_UNIT($,.METRE.));

In this line, we can change the "$" character like this:

#815=(LENGTH_UNIT()NAMED_UNIT(*)SI_UNIT(.MILLI.,.METRE.));

Then save the file, then re-import the STEP file.

Import After Fix

This is how the imported part shows now: