CAD drawing and crop question

[Iainy1961]

Hi all, I working with a very big CAD drawing but on ly needing one hall of this mamouth exhibition centre. The imported CAD has hundreds of classes and is really slowing my computer down every time I have to zoom or move around the drawing. I have been trying just to crop out the one hall I need to work on, this is proving way more difficult than it should be I think. It is a 2D only document. Any ideas how I can crop out the piece I need? I have the CAD layer and classes set to modify but I just can't seem to find a way to crop out. Also I tried to put it into a PDF and crop from there but the vectors in the CAD just about shocked Adobe into submission. Anyway, any ideas would be very welcome.  Thank you.

[markdd]

Two options. 
 

Import as a reference inside a design layer-referenced viewport and then add a crop object to the viewport. This will also exclude all of the hundreds of classes from your file.

 

If that isn’t an option, then try using the clip tool in the second mode to crop away geometry outside of a rectangle that you create with the tool.

Edited September 5 by markdd

[mjm]

or secondarily, try to copy paste what you need from the original doc into a fresh VWX drawing

[Pat Stanford]

Or if you want to delete the objects rather than just crop the view of them, draw a marquee to select the objects you want to keep then choose the Invert Selection menu command. This will deselect all the selected items and select all the deselected items so you can delete them.

 

[bjoerka]

use the purge tool to ensure that there are no coiincident object.

delete everything that you don´t need. often in dwg imports there are hundreds of unused symbols which blow up the file size.

and check the line styles inside the drawing. sometimes there are styles that seem to be continuous but consist of small dotted lines and slow down the whole system...

 

[Iainy1961]

@bjoerka @markdd @mjm @Pat Stanford  Thanks guys, I don't know what is going on in this CAD drawing, the deeper I get into it the worse it gets. Nothing works like it should, or rather, I can't make it work like it should. There are so many viewport classes and it took me ages just to sort out the origin of the drawing. I think it might have been clipped from a master CAD of the whole site. The site is around a mile by a mile and a half. The scale was set to 1:2e+00. So I am going to look for a PDF of the venue.  Thanks again

[VIRTUALENVIRONS]

I had the same trouble,  Below is the plan view of Australia's Olympic Park.  Quite large.  Could not break it down.  Eventually exported an image file to the size I wanted and extracted elements required.

Sheet Layers seem to be problematic.

 

 

 

 

[VIRTUALENVIRONS]

16 hours ago, Iainy1961 said:

any ideas would be very welcome.

There is one more thing you can try.  It does depend a bit on the file.  

DXF separates components based on line color.  So, export your file as a .dxf and then import it again.  This did work for me on the file I showed, but I only thought of this after I completed the project.

 

On this file, it separated all the components.

Edited September 6 by VIRTUALENVIRONS

[grant_PD]

Referencing will bog down your computer. 

I would keep the master document in its own file, select only the 2d stuff you need from it and copy/paste in place into your file.  

[Iainy1961]

@grant_PD  This file is all 2D. I will ask the venue for a PDF print out and scale it from there. Also this CAD file is from 2016, so I don't know what that is doing to the conversion. Thanks for you help though.

[bjoerka]

just for those who also replied.

i looked into the dwg. whoever was the owner of that file - he never checked this file.

even autocad became sluggish.

symbols scaled down by the factor 0.034xx somewhat. drawing contents inside these symbols that have been place on the first corner on the moon .-)

dashdotted linetypes that you can´t see even when zooming in as near as possible...

and finally - whatever units the file was imported - it never came in in real world measurements .-))