Reducing Large CAD file size

[Anonymous]

I have a CAD file that is 280MB and must get it under 20MB to be able to email it. I cannot do a dropbox/file share or zip the file because it will be shared to people inside and out of my company that don’t know how to unzip or use file share programs. The drawing is warehouse layout with a lot of detail blocks for robots and other automatons. The person who originally created it just copied and pasted from other drawings. Mostly what he copied was exploded blocks & exploded hatching. I started out by using overkill, purging, and auditing the drawing. I redrew the 3D objects to be 2D. Then I made a xref of the building, since we only working with the equipment. This got me down to 175MB. Then I just copied it and pasted it into a new blank file. Now by deleting the exploded hatching and redrawing some items has gotten the drawing it down to 76MB. Is there anything else I can do to further reduce the file size?

Also, is it a big deal when working on a 2D drawing if lines/objects are at different “Z” coordinates heights?

[dmfrazier · Accepted solution]

To see if more "stuff" can be removed, try -PURGE with all of its several options.

See this article (and its links) for more suggestions:

https://knowledge.autodesk.com/support/autocad/learn-explore/caas/sfdcarticles/sfdcarticles/Reducing...

"is it a big deal when working on a 2D drawing if lines/objects are at different “Z” coordinates heights"

It can be a big deal.

The FLATTEN command might fix most of this.

[Johanna_Esteban]

Hi @Anonymous, 

You can use WeTransfer for send the file.

Is very easy and the user download the file without user accounts.

Best regards, 

[Anonymous]

I use that and other file share programs. My co-workers are the ones that do not know how to use any file share sites/programs. They are also all over the country. So I can not just put it on a thumb drive, and take it to them.

[Anonymous]

I also tried flatten but this didn't move the lines to one plane. I'm the only one that has full blown AutoCAD, everyone else is using AutoCAD LT. So, they don't even realize that lines/objects can be above or below each other. As I redrew this file, made sure everything was on the 0 elevation. I just didn't know if a totally flat "2D" drawing would increase the file size.    

[Anonymous]

It sounds like you have taken most of the simplest steps to address file size. One thing that I have noticed is that detailled blocks (and revit created blocks) frequently generate a lot of splines, which are fairly space intensive. You can filter those out, and see of that helps. Alsodoes the file have a lot of points?

I also have a LISP routine that I use for serious cases, which I can forward.  The reason I hesitate is that it erases everything below a user specified length, and that can erase whole lines that are made up of little tiny segments.  It can be quite destructive.

For me, the Z coordinate issue only comes up when I start snapping to objects. There are routines that try to reset z to 0, but it depends what the entities are. You can use the view cube to see a side view, which can help you diagnose where the problems are. From there you can window select items that are "flat" but at the wrong elevation, and change the elevation property to 0. That approach doesn't work when the line is drawn in 3d. Because it moves the whole line (not the end)

[dmfrazier]

Another thing to consider (perhaps for the future), assuming the DWG was set up with layouts, is the ExportLayout command.

"I just didn't know if a totally flat "2D" drawing would increase the file size."

A "totally flat 2d drawing" would be smaller in size than a comparable drawing with objects defined with different z-coords.

[LyleHardin · Accepted solution]

Freeze anything that does not need to go with the file.

Use WBLOCK and select what is still showing. This will create a new dwg and leave all the stuff you don't need (on frozen layers) behind. It may not get down to 20 meg, though.

You could also WBLOCK out one or more layers at a time to several dwgs, then they can reassemble everything on their end.

Before all that you could try running OVERKILL to delete duplicate objects. Do a little at a time first. Don't select everything... that might take a while or lock your machine up.

Save first.

[Anonymous]

I work for a large logistics company and just a single drawing goes through so many people. We normally get the building drawing from the architect or landlord. The building being requested could also be a drawing we already have on file. Our sales team draws a very crude layout to sell to our proposed client. No one makes a block or Xref of the building. They just keep erasing and drawing different layouts until we have a contract. It then gets passed to our IE's to erase the concept, and make a new layout that flows better. Then it is handed over to my group, which buys, and installs everything drawn into the building. By this time the file sizes are kind of large, 10-12MB. That's when I overkill, purge, audit, flatten, and split it into 2 different drawings. A equipment xref and a building xref. I try to see if I can get the original building drawing to use that as my xref. This keeps the file size small but every once  in a while we get these huge files.

[dgorsman]

Have you checked for excess annotation scales?

How about DGN line type bloat?

Have you purged REGAPPs (typically a small portion of bloat size, but every bit helps).

Have materials been purged, or at least tracked down to associated objects so they can be removed and purged?

Is there vertical data from Map3D and/or Civil3D coming along for the ride?

[serkancavuslar]

Hi @Anonymous ,

[serkancavuslar]

Hi @Anonymous 

[Johanna_Esteban · Accepted solution]

Hi @Anonymous, 

To lighten the file, basically what should be done is to debug it as you have been doing.

The level of detail matters but is not often appreciated; if what you are looking for is to specify in a large space it is enough to work with light blocks, that will minimize the amount of elements in the file. Everything that is going to be used several times is better to use as a block, in addition to generating additional changes if necessary because there are more than one.

And if 3D is not required, then nothing better than replacing it with new and clean geometry. If possible, avoid ellipses and splines, instead use arcs and lines.

FILTER is definitely a great tool, since it allows you to play with all the content of the file, work it little by little and correct in several entities at the same time if they present the same problem as THICKNESS in the lines, without a 3d.

This is hard work, but it is worth the effort.

Best regards,

[GeeHaa]

Hi,

I'm not sure if this will help, but have you tried the OVERKILL command?

[Anonymous]

Yes. That was one of the first things I tried. I even went into each block used Overkill. After working with Johanna, we figured out that there is just so many items (over 30,000 lines, arcs, splnes, etc.) in each block. I suggested we just have the outline of the robot, and not all the detail, but they didn't want to do that. We finally got it to 40 MB & they are just going to use that. They have worked on this for so long they just don't care any more how large the file is.

So thanks to everyone's suggestions, and Johanna's time to help with my question.