Dwg import and deleting unwanted classes

[MarkS-Novak]

We often receive dwgs where viewports are set up with the desired classes visible but the design layer has hundreds of undesirable classes all visible all jumbled on top of each other. How can we delete these unwanted classes without hunting and pecking one by one?

Sadly the organization menu allows you to see those invisible in the desired viewport, but you cannot select and delete these en masse.

Custom selection tools do not seem to offer the kind of help needed either. You would think there would be a way to simply "tag" these clases for deletion in the design layer mode.

Any help is greatly appreciated.

[mike m oz]

This illustrates the problem of with the DWG import and export process. The focus is on the integrity of the DWG information rather than the communication intent.

In this instance all the user really wants is a DWG file containing only the information that is contained in the view. Unfortunately that is not what he gets.

[gmm18]

Import the DWG into a new blank file. Save it.

Then in a separate file (you actual desired file you are working in and want to show that DWG info):

Create a referenced Viewport selecting that DWG import file as the source. This is great because it doesn't bring all of those classes into your file, keeping your class list nice and clean, but you can still adjust the visibility of the original DWG classes by selecting that reference VP and using the Object Info Palette.

[D Wood]

Tools>Purge Unused Objects may be useful.

[mike m oz]

gmm18, David - both of those are good strategies to use with DWG, but neither of them will solve Mark's problem.

Mark, one way of simplifying the process might be to look at the Viewport and note which Classes are turned off in it. Then go back to the Design Layer and turn off those same Classes.

You could do the opposite ie. turn on only those classes which are off in the Viewport and then delete all of the objects with those classes. The problem with this though is you may have deleted information you later want. You also need to be mindful of "container classes". Deleting an object of a particular class may also delete objects within it that are a different class.

The focus with DWG import and export needs to be changed to communication intent rather than lets translate everything:

- With DWG export the user wants the recipient to get the information that they have shown the way they have shown it.

- With DWG import the sender wants the user to get the information that they have shown the way they have shown it.

The DWG import and export processes need to have both options - ie. communication intent and complete import / export. Communication intent should be the primary option though, because 95% of the time that is what the user will want.

[Jonathan Pickup]

class and layer mapping can help out here when you are receiving dwg's from the same consultants.

the online user group covered class and layer mapping last month:

http://www.archoncad.co.nz/usergroup/join_int.php

[brudgers]

I've sent and received files both ways...some carefully edited to just what the sender thought was relevent, some which are just a 'data dump.'

At this point, I lean toward the data dump when I send files.

I have concluded that trying to guess the workflow of other people is a waste of my time...and more importantly a source of excuses for those with whom I share my data.

Sometimes I long for the old days of sending a hardcopy and just letting the consultants cowboy up.

[David Bertrand]

As gmm18 suggests, can't you simply import the dwg into a new drawing, purge it, and then save and insert it into your project?