Thursday, 21 November 2013

Copy/Monitor & Batch Copy for MEP Update

In the previous post, I made a partially correct statement and want to elaborate more on it. I said that re-hosting doesn’t work, but turns out it just failed in my particular test files due to some special circumstances. In general it should work.

When re-hosting fails

In the test files, ceiling-based fixtures were used. When this model was linked and I ran Copy/Monitor, Revit took that ceiling-based fixture and modified it without my knowledge (no warning was ever issued). The copied fixture was not the same version as the original one and it turned into a pseudo-version of a face-based family that is different than a true face-based family: Geometry was on the bottom of the face rather than the top, and there were “remnants” of the original ceiling-hosted fixture, such as a “Ceiling” reference plane. When I tried re-hosting the pseudo face-based fixture, Revit complained and wouldn’t do it.Cannot HostI suspect that the above is due to the trick that Revit is trying to play. Here is the original fixture:


The following is the modified copy/monitored fixture. There is a perfectly valid reason Revit did this, because in the host model there is no ceiling geometry:


However a true face-based family would be like the following image. Note how geometry is built on the top face and there is no “Ceiling” reference plane. I think this is the reason that Revit is unable to re-host the family shown above.

Face-Hosted family

When re-hosting works

When copy/monitored fixtures are face-based from the start, Revit does not need to do modifications on the fly as described above. In this case, re-hosting works as expected. So if you are faced with copy/monitoring of hosted fixtures other than face-based, such as ceiling or wall-hosted, make sure to use the type-mapping feature, so hosted fixtures are substituted with pre-loaded face-based families.

Final thoughts

There is definite room for improvement in linked model workflows, especially for the MEP disciplines. The recommendations for transferring light fixtures from a design model to the final documentation model are as follows:

  1. Use face-based families whenever possible and name hosted fixtures clearly so they can be recognized and substituted;
  2. Use the batch-copy feature and specify the type mapping so hosted fixtures can be substituted with pre-loaded face-based fixtures;
  3. If you are not going to monitor fixtures for changes in location, do not use the dedicated Stop Monitoring tool. Instead, remove the link and re-link again when needed. This way copied fixtures can be moved around freely without the need to re-host them.

Wednesday, 20 November 2013

Copy/Monitor & Batch Copy for MEP

The Copy/Monitor tools tend to be a Love/Hate relationship in that very order. In fact we have recently been using the batch copy functionality because we sincerely love it due to its flexibility. But that love is fading quickly due to some unexpected repercussions.

A common scenario to employ this tool on, has been when a Lighting consultant/designer is working in a separate model (for design purposes only, not for documentation) and our Electrical Engineers need to circuit these lighting fixtures and document them in their power and equipment drawings. These fixtures need to be hosted in the electrical model for proper circuiting. Copying and pasting fixtures one by one from the linked lighting model is highly inefficient. Opening the source model to copy and paste into the documentation model also doesn’t work due to hosting issues (most of these families are face-based and cannot be pasted) and also due to the fact that Paste >> Aligned to Same Place uses the Internal Coordinates to determine location and this is not always consistent between models. On a side note, best practice dictates that you link other discipline models via Auto – Origin to Origin to avoid these problems.

We have received several reports and anecdotes of performance degradation when copy/monitored fixture counts are high, so we have been disabling monitoring soon after the copying is complete and resume with manual coordination from that point on.

Stop Monitoring

Unfortunately when you stop monitoring by using the dedicated tool, MEP categories become pretty much useless as they can no longer be modified!

Cannot moveNo Host

EDIT: Refer to this post. If you try re-hosting, you have to use the workplane positioning option, which is not desirable. I am not sure why Revit even asks you to do this because copy/monitored elements do not have a host in their properties.

There seems to be no work-around, short of deleting all fixtures and starting over, which is really bad. Lesson learned: Do not stop monitoring with the dedicated tool! If you want to stop monitoring, remove the link. Once you do this, none of the MEP categories will behave as shown above and you can freely move them around and re-monitor at will. These categories then pretty much start behaving as Levels, Grids, Columns, Walls and Floors, which we can stop monitoring at any point without experiencing the same repercussions.

At least we now have a plausible workflow for future projects and the love for the batch-copy tool has been (cautiously) restored.

Coordination Settings

The nice thing is that you can specify type mapping and only batch-copy one fixture type at a time. Just make sure that if you want to use this as a pure copy tool with no monitoring, to then remove the link soon after. You can re-link it back in, but this is currently the only safe way to stop monitoring without putting future revisions to the position of these fixtures in jeopardy. Autodesk has recorded this behavior but there is no estimate when this will be addressed.