translating revit drawings into autocad layers

[bnix]

the project i'm working on requires exporting my revit drawings to autocad drawings with percise autocad layers per a layer standard that i must follow (clients requirements). i wanted to know what is the best way, if any way, to assign layers of my choice to the elements and objects i've created in revit. Or is there a way of exporting that can translate the revit drawings to the autocad layer system? I don't know where to go from here, any suggestions?

[sbrown]

Under File Import/export settings, export layers dwg, you can set what layer and color each object style exports to.

[PaulB]

You may well be able to set the majority of layers but there are still quite a few items like hatching, etc. that will not translate directly. There are also items that don't get broken down far enough in terms of layer separation so that may also be a problem.

This has been a common issue now for years even with AutoCAD so in effect you are no worse off than you were in using AutoCAD only. Most of the consultants will do the complete drawings using there own layering system due to having lisp routines etc. that specify certain objects to be on certain layers and would only convert a small proportion of the drawings at the project completion.

So the answer is that the facility is 90% there but you will need to tweak a few layers to get full compliance.

Paul

[sbrown]

Paul is correct. I recommend you either plan in the amount of time it will take to "clean up" you exported dwgs or tell the client you cannot fulfill that portion of the contract. In our experience you will not beable to produce a complete AutoCAD set of documents exported from Revit. The export function works great for consultant backgrounds and sharing workload, but was not designed to allow you to translate an entire document set in Revit to a document set in AutoCAD. The 2 programs work and act diff. I know firsthand the Revit team is working very hard to make the export process work as well as it possibly can.

If I were in your shoes I would not take on a job that had to have DWG's as the final deliverables and use Revit on it. You will spend more time fixing you exports than you took to create the model.( I may be exaggerating slightly, but not too much).

Recognize that when Revit exports a plan for example it only exports exactly what you see of that plan, it doesn't think like AutoCAD where you would have one background plan xreffed into multiple sheets at multiple scales,etc.

So if the client typically uses AutoCAD and knows how it works they will look at your exports and think you have no idea how to use AutoCAD.

So just make them aware that the files they receive will not be what they are used to. Suggest DWF for deliverables.

[Steve_Stafford]

Scott and I have worked together on projects whose terms have tested the boundaries of what Revit can be expected to do exporting to dwg. Both reasonable and un-reasonable demands placed on Revit by the nature of a fairly large portion of our work load. Recently I've personally spent a great deal of time on this issue. I am confident that it will get due attention from Revit's team.

If you care to read more about this, rather than cluttering up this thread with 2 pages of text in-line, I've attached a pdf of a summary of the issues we have identified based upon our experiences so far.