Rhino blocks to revit family, Issue with mirrored blocks

I am trying to convert rhino blocks and place them in revit as family instances. Everything is working as expected, except when the block instances are mirrored, all mirrored instances do not keep the correct orientation.

Is there another way to solve this issue without limiting the use of the mirroring blocks in rhino?


This is really tough, in general Mirroring produces inconsistent ‘handedness’. A part that is mirrored may not be able to manufactured as the same part. Say a mullion cap with a milled out edge.

Rhino flips the Z, which is what actually happens, two parts that if manufactured would not be identical.

Revit uses a Flipped Face Flag, or Handed Flag depending on the element. So the Z remains the same but it internally flips per one Axis of your choosing.

If the Block/Family is conceptual and symmetrical then rotating the Block 180 via the center is recommended, vs mirroring.

Thanks @Japhy ,I’m setting this workflow only for early design/conceptual phases. We will be using different families if it makes it past the Schematic design phase. Good to know about this. I will rotate the blocks 180 degrees from the center of the geometry.

In this example this is a simple mirroring on a flat surface.
Can this rotation logic still be applied to 3d rotations and then mirroring of blocks?

Sahil, The process for a symmetrical block would be to copy the block, Rotate 180. The family creation would still remain the same. Transform block geometry to 0,0 (if its not there already) to create the Revit Family. Then using a Work Plane based Family in Revit place instances of that Family by the Rhino Block Instances Planes. I think you know most of this but want to make sure we are on the same page.