So this blog is a brief discussion on why it's great to receive 3D fab shops, especially if the engineer is using Revit or any other BIM tool. To start, one of the latest projects we have been working on used correct 0,0,0 reference points all the way across the board! Even our civil had the model in the right place! We had a great kickoff and coordination meeting, which helped and we tackled quite a few of the issues regarding,
What is our project's reference point?
What is true elevation vs. level elevation?
And how in the world do you model a giant sombrero? (this last one was for fun and the answer was with sweeps)
Here is where it got fun, our subcontractors were all using 3d in one form or another. Cue drum roll........model overlay!!
So forget the old way of maybe having an MEP model or trying to cram in a thorough clash detection using the fabricators model towards the end of the project. This time we had all pistons firing. And Brian and I had been dying to try this, thus, we loaded into Navis, the engineers model first (which we had worked through the clash detection on) then we loaded in the fabricators model.
Next words out of our mouths, "Holy buckets!" this is off here this is off there...etc. Also finally got a chance to use NavisWorks' "reverse" clash detection tool that let's you know when one model is not aligned to another by the defined tolerances! (I recommend the old F1 button to learn how to do this correctly but it helped us out immensely.)
I digress... The end result of this was that we found the fabricator had taken some "shorter runs" that worked out fine and saved the project money in length of ductwork runs and some that didn't because the engineer required a longer drop, certain friction for their flow rates, etc..
So ductwork got cut by about 23%. Reran the clash using the approved fab model and went from there.
I love collaboration.