To create a Stack-Up of 2D files for a six bay by twelve bay structure with nine mechanical levels is a feat I'd like to see.
How did they used to do it before 3D?? Guesstimate
A LOT more work because the files were LESS usable.
The same way you check any 3D model, you check it.
So your machining is deadly accurate? I'm sure if that were the case there would be many manufacturers banging down your door.
How do you get your tolerancing and datum structure for checking? Doesn't that come from the 2D??
Our models are deadly accurate, our machining is within tolerances which are noted in the spec. Keep in mind that I did NOT say that 2D was useless.
Oh? Even out local hardware store uses a 3D modeling tool to design kitchens and bathrooms with customers, right in the middle of the store (there's the MORE useful part). Then drawings are extracted from the models with complete parts lists and installation instructions for the DIY'er.
Isn't that 2D?? So they are building from 2D, yeah? Also the 3D viewing is for Joe Consumer to get a visual of what his kitchen will APPROXIMATLEY look like. (note: not accurately)
Keep in mind I did NOT say that 2D was useless, just that 3D was MORE usable, just as this case points out. The 3D model was much MORE usable showing the client what his kitchen looked like than 2D drawings would have ever been.
We have several stations in out shops for viewing the models during fabrications and several more on-site during construction. It is the norm in our business. Seems it would be a lot easier to accomplish for the average architect.
I don't know many Archs that do routine site visits unless there is an issue. ( I don't think they like to get dirty 
) They do the design and let the GC do the building. In the last 3 years I have yet to see a GC with AutoCAD in the field.
That will change as the work force changes, as it has done in many other fields. My father in law was a machinists, his hands were permanently blackened by oil, grit, scale and steel. My younger cousin is a machinists, and works in a white shirt, his hands are never dirty.
Not at all. I have some parts (so do many machinists) that are cut directly from the model without EVER existing on a 2D drawing.
So have I but with out the tolerancing or means to accurately check them,getting them to preform with other parts is a problem.
We have that data, why don't you?
My drawings are of the 3D model if you flatten the model, the steel that used to reside in the view slice at elevation is now at zero and my plan viewport is empty (all my plan viewports are empty), the steel in the elevation of column line A now appears to be a single line at the bottom of the screen as it does in all the other elevation views. Others have used similar routines to do just that.
But is the plan view still accurate??
Not anymore, all nine levels of the structure now interfere with each other at elevation zero.
If you flatten a dwg to the plan view, does it make the plan view any less accurate than the 3D plan view? If I took the 3D plan view and printed it to 2D paper. I then flattened the 3D to the plan view and printed it to 2D paper, would they not be the same?
The plan view of the 3D model at Top/Steel Elevation 109'-0 will show only the framing at that level, as will the plans at TOS 112', 122', 126', 136' and so on. Once flatten all the steel will be at the same level (zero) and all running into one another. As I said, it will destroy the file.
And that is my point about the supplied sample.
So you would agree that an accurate 3D flattened to plan view would produce and accurate 2D plan??
[/quote]No I don't, never have. It may in some cases for some users, in our case it would be disastrous.
