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CAD Forums => CAD General => Topic started by: ArgV on September 12, 2009, 03:05:19 PM

Title: HOW many XREF's can be used.. and..
Post by: ArgV on September 12, 2009, 03:05:19 PM
I'm wondering if it is possible to, like solidworks, make complete drawings with nothing but xrefed parts.. even if a drawing  contains hundreds of blocks? and also if this would be a reliable way of doing things, or even a preferred way of building models.

thanks!

-ArgV

Title: Re: HOW many XREF's can be used.. and..
Post by: James Cannon on September 12, 2009, 03:13:49 PM
Absolutely.

I can't speak as to an actual limit on the NUMBER of XREFs ALLOWED in a drawing, but using many many XREFs in a manner such as part libraries in Inventor/Solidworks is a great way to organize and reduce error.

The guys that do our piping design for some of our larger processing plants do this.  They'll have a separate .DWG for 6" Butterfly Valve, 4" Flange, etc. and will just XREF in the necessary parts to complete their piping design, apparently.  It creates a bit of a large folder/subfolder/subfolder assembly of XREF files, but it's actually not hard to manage at all.

One of the -BIGGEST- benefits I find, is that you don't have to mess with the layer manager when needing to turn some things off.  Having a large tree of XREFs allows you to simply "unload" the things you don't want to see at the moment.

For instance, if I'm working on updating finish grades of my foundations under the tank pads, I can turn off all of the piping model except the tanks, equipment, and leave all the civil and structural series XREFs on.

For larger projects, I would never go back to doing it all as blocks and simple drawings... having a large number of XREFs is the only way I can keep my sanity when managing the CAD work for such large projects (large to me) 

In fact, some files contain nothing except XREF data... the overall PIPING XREF has no objects (lines, plines, blocks, text, etc) in it... simply XREFs of sub-assemblies.  The overall STRUCTURAL XREF has no objects in it... just hte xref's subassemblies for each platform, pipe support, foundations and other structural elements.  Then there is one large container file that XREF's in all of the discipline files to create the entire model of the project.  So the top two levels in my XREF tree, really has no objects other than XREFs in them.
Title: Re: HOW many XREF's can be used.. and..
Post by: ArgV on September 12, 2009, 03:56:32 PM
Absolutely.

I can't speak as to an actual limit on the NUMBER of XREFs ALLOWED in a drawing, but using many many XREFs in a manner such as part libraries in Inventor/Solidworks is a great way to organize and reduce error.

The guys that do our piping design for some of our larger processing plants do this.  They'll have a separate .DWG for 6" Butterfly Valve, 4" Flange, etc. and will just XREF in the necessary parts to complete their piping design, apparently.  It creates a bit of a large folder/subfolder/subfolder assembly of XREF files, but it's actually not hard to manage at all.

One of the -BIGGEST- benefits I find, is that you don't have to mess with the layer manager when needing to turn some things off.  Having a large tree of XREFs allows you to simply "unload" the things you don't want to see at the moment.

For instance, if I'm working on updating finish grades of my foundations under the tank pads, I can turn off all of the piping model except the tanks, equipment, and leave all the civil and structural series XREFs on.

For larger projects, I would never go back to doing it all as blocks and simple drawings... having a large number of XREFs is the only way I can keep my sanity when managing the CAD work for such large projects (large to me) 

In fact, some files contain nothing except XREF data... the overall PIPING XREF has no objects (lines, plines, blocks, text, etc) in it... simply XREFs of sub-assemblies.  The overall STRUCTURAL XREF has no objects in it... just hte xref's subassemblies for each platform, pipe support, foundations and other structural elements.  Then there is one large container file that XREF's in all of the discipline files to create the entire model of the project.  So the top two levels in my XREF tree, really has no objects other than XREFs in them.

Sweet! That sounds like what we need, as we share many parts between drawings, and it gets tough to figure out which parts we have where, and then the biggest thing is when we need to update something, we have to go change everything in EACH master drawing for these parts.

As far as managing Xrefs (a HUGE amount of them!) I see an advantage of just keeping all blocks and xrefs in ONE folder to minimize duplicates, and make searching very easy. Does that make sense? being kindof new to autocad and Xrefs in general, not quite sure how to go about this.

thank you for your reply!

-ArgV

Title: Re: HOW many XREF's can be used.. and..
Post by: James Cannon on September 12, 2009, 03:59:13 PM
The number of XREFs you have, I think, will depend on how you organize them.

The piping guys have a LOT of files they use as XREFs routinely, and have created folders to organize types.  They  have a folder for FLANGES, a folder for VALVES (then a subfolder for TYPE of valve) and a file for each size, in each of those folders.

Your organization is entirely a personal choice, I believe, as to what you think is best and how you prefer to work.

It -may- cause slightly less problems with pathing the XREFs if you have them all in one folder that never changes, but I honestly haven't had a problem with XREFs using a number of folders/subfolders to organize them logically... and even if I did, I imagine the REFERENCE MANAGER would make quick work of it.
Title: Re: HOW many XREF's can be used.. and..
Post by: mjfarrell on September 14, 2009, 12:07:43 PM
I'm wondering if it is possible to, like solidworks, make complete drawings with nothing but xrefed parts.. even if a drawing  contains hundreds of blocks? and also if this would be a reliable way of doing things, or even a preferred way of building models.

thanks!

-ArgV



That is the Theory anyway, I would advise that you use RELATIVE pathing for your XREFS, and get aquainted with eTransmit.
Title: Re: HOW many XREF's can be used.. and..
Post by: James Cannon on September 14, 2009, 12:11:19 PM
Seconded on both accounts.

Very much so!

Relative FTW, and etransmit is a handy, handy tool :)
Title: Re: HOW many XREF's can be used.. and..
Post by: CHulse on September 14, 2009, 12:44:23 PM

That is the Theory anyway, I would advise that you use RELATIVE pathing for your XREFS, and get aquainted with eTransmit.

Wise words, me thinks...
Title: Re: HOW many XREF's can be used.. and..
Post by: Dinosaur on September 14, 2009, 12:55:35 PM
Ad never, ever, EVER put an XREF on Layer 0 ... I would further advise using a separate layer for EACH XREF.
Title: Re: HOW many XREF's can be used.. and..
Post by: CHulse on September 14, 2009, 01:12:23 PM
Another point of caution:
Keep the UCS set to WORLD...
Title: Re: HOW many XREF's can be used.. and..
Post by: Tankman on September 14, 2009, 11:19:36 PM
Another point of caution:
Keep the UCS set to WORLD...

Always the UCS is set to "world."  Piping, is on a layer, tanks on their layer, etc.
UCS is "world" on all layers.
Title: Re: HOW many XREF's can be used.. and..
Post by: t-bear on January 26, 2010, 09:46:33 AM
Ad never, ever, EVER put an XREF on Layer 0 ... I would further advise using a separate layer for EACH XREF.
I have to agree strongly on this point.  Many of our xrefs have multiple layers within the xref.  If the xref is on layer "0", it becomes a real mess to deal with turning off or freezing layers within that xref.  ALWAYS place your xrefs on their own layer!
We often have xrefs that go 5 deep or more.  The only way to handle large projects!!!