To XRef or Not to XRef

[irneb]

As the bard said: "That is the question." Although actually in this case: "That is the start of the questions." A lot of people use a set of DWG's in which they draw the actual linework. Then have a set of "Layout" DWG's which each simply XRef one of those drawings to make it into printable sheets.

As far as I can determine, it's not truly necessary just for this purpose to use XRefs. Maybe it's a spin-off from earlier versions like R14 where you only had one "Layout Tab". Could anyone please provide other reasons for using this (or alternatively for not using) method of drawing organization, instead of using multiple Layout Tabs in one drawing?

I'm thinking there's no benefit, only extra DWG files and several duplications when eTransmitting. E.g. you have a floor plan, which is split into 4 sheets. If you use the XRef method, you've got 5 DWG files. And if you eTransmit you've got 4 ZIPs, each with a copy of the entire floor plan DWG. Whereas if you use the Multi Layout method you've only got one DWG file and one ZIP.

[mom of 3]

I will just give an idea as to why we utilize the xref command.

at my company, we work with several different disciplines, in addition to outside client drawings.

example:
we (civil) draw our base drawing, survey draws their base drawing, electrical draws their base drawing, architectural draws their drawings, etc. say I need the survey & arch drawings in my drawing. I will create my layout sheet, xref in my base drawing, the other 2 drawings & my title block. that way, I can use the other drawings & not change any of their linework, yet if, say arch, changes their floorplan, it will automatically update in my xref.
take the same instance above, but add a client drawing to the mix. we can not change their linework, so as long as they send us a current drawing, we xref it in to show their work as well.

our drawings will still have multiple layout tabs, also. if we send something out, we still only have 1 .zip file going out.

I hope this helps.

[irneb]

Thanks for the response, I know that when you've got to combine different drawings XRef is the way to go.

I will create my layout sheet, xref in my base drawing, the other 2 drawings & my title block. that way, I can use the other drawings & not change any of their linework, yet if, say arch, changes their floorplan, it will automatically update in my xref.

Now how's it impossible to XRef say the Arch drawing into a combined base/layout drawing?

our drawings will still have multiple layout tabs, also. if we send something out, we still only have 1 .zip file going out.

Now here's exactly why I don't like this method. What do you do with your revision column? It's been noted here that if you use the base dwg / layout dwg route you have to modify at least 2 drawings whenever there's a change. When it's a large prj and 30+ people working on it at the same time this can become a headache. So we've placed our revision columns & a TXT for current revision in Model Space so you note the change in the base DWG. The problem here is that these then clutter up the Model Space, especially if you XRef it into another or have 2 (or more) base files in the same layout.

See what I mean by the questions just become more and more?

[arshiel88]

Xrefs are like blocks. We use blocks if you use this block over and over again. The only difference is that this External block definition does not add space to your drawing. If you don't use xref and you copy each base plan on each drawing, you will end up with a huge file on each drawing. One more thing about layout tabs is that too many layouts also result in significant slow down of regeneration especially when your layout consists of 2 or more viewports.

[jpaulsen]

Could anyone please provide other reasons for using this (or alternatively for not using) method of drawing organization, instead of using multiple Layout Tabs in one drawing?

Your question is a little different than the title of this thread. Maybe you have two questions one regarding xrefs and one regarding multiple layouts in a drawing.

The advantage to xrefs is when line work needs to be in many drawings you only have to update it in one place. It is also the easiest way to manager drawings from other consultants.

Some of the advantages to having many layout tabs in a drawing are time savings not having to open multiple drawings, the ability to change a layer properties in one drawing instead of many and labeling between sheets is generally easier to coordinate.

Some of the disadvantages to having many layout tabs in a drawing are only one person can easily work on all the sheets (layouts) at one time, you can not use xclip anymore with out having many occurrences of the xref.

[Opie]

Your question is a little different than the title of this thread. Maybe you have two questions one regarding xrefs and one regarding multiple layouts in a drawing.

The advantage to xrefs is when line work needs to be in many drawings you only have to update it in one place. It is also the easiest way to manager drawings from other consultants.

Some of the advantages to having many layout tabs in a drawing are time savings not having to open multiple drawings, the ability to change a layer properties in one drawing instead of many and labeling between sheets is generally easier to coordinate.

Some of the disadvantages to having many layout tabs in a drawing are only one person can easily work on all the sheets (layouts) at one time, you can not use xclip anymore with out having many occurrences of the xref.

All of these reasons are why we use them. We even have multiple XREFs for different aspects of the project. A drawing for the property, one for the existing topography, one (or more) for the design elements. We work in the Civil field, and this seems to work for us.

[mom of 3]

Now here's exactly why I don't like this method. What do you do with your revision column? It's been noted here that if you use the base dwg / layout dwg route you have to modify at least 2 drawings whenever there's a change. When it's a large prj and 30+ people working on it at the same time this can become a headache. So we've placed our revision columns & a TXT for current revision in Model Space so you note the change in the base DWG. The problem here is that these then clutter up the Model Space, especially if you XRef it into another or have 2 (or more) base files in the same layout.

our revision column is on our titleblock. if a change is made, it's made in the base drawing to which it applies. the revision is then clouded on the layout tab to which it affects, numbered, & the revision is noted on the title block - all in paperspace. it has never caused any headaches for us.

[irneb]

our revision column is on our titleblock. if a change is made, it's made in the base drawing to which it applies. the revision is then clouded on the layout tab to which it affects, numbered, & the revision is noted on the title block - all in paperspace. it has never caused any headaches for us.

I'd have liked to use this method as well, unfortunately the protocol here is to describe each and every change, give a reason for it & indicate which of the consultant's (or other e.g. Client, PM, QS, etc.) caused the change. This is due to previous problems with projects, i.e. to cover our backside. So you can imagine the revisions column gets a bit long by the 5th revision. The issued drawing only shows the latest few revs but has all the history in Model space, we either move the table in MS or pan the viewport in PS.

Your question is a little different than the title of this thread. Maybe you have two questions one regarding xrefs and one regarding multiple layouts in a drawing.

You're correct, the title doesn't exactly describe what the question is about, maybe it should read XRef vs Multiple Layout. I'm trying to gather as much reasons for and against this as we're now considering formalizing the idea of how we organize our drawings.
You're all correct about the general use of XRefs, having several advantages to drawing everything in one file. I should have made it more clear, that I understand the reasons for XRef in general (multiple users, re-use of one DWG, etc.) However I'm more concerned with why have 2 files where one only has the PS and the other only has the MS? The reason is that we've had so many problems with eTransmitting XRefs that we want to have a particular drawing number for each DWG file. If you use one of these as an XRef in another, so be it, but still each DWG is a full fledged drawing in its own right - i.e. an issuable numbered & revisioned drawing in the Drawing Register.

[dxarhoulakos]

Our projects are very large. Usually somewhere between 2 and 5 million sq. ft.

Typically we have anywhere from 5 to 20 people working on a project at the same time.

Our drawing sets can have close to 1000 sheets...

We use xrefs quite extensively...

All sheet files are built with xrefs
We also xref whren building different views: for example when drawing an elevation, we xref in the floor plan. When drawing the floor plan we xref in the elevation...

We also use this for checking consultant files, which has been mentioned a lot here already. (actually we're moving away from this though. we're beginning to share DWF files with consultants instead...but you need '08 to do this affectively)

I tell people this basic rule of thumb: If you have to draw it more then once...xref it

I guess, if you're one preson working on a project. and you dont have too many sheet files, i can see using your method. But as soon as you add another person to the team, you're unable to do this anymore.

[vtmiii]

if it was not for xref's and tabs we would increase the amount of hd space on the server.
xrefs make it easeier to update the drawings vs re-inserting base plans as blocks (i 've been using autocad since version 2.6) which take up time to do verse working on the actuall drawing itself (saves us about 3 to 5 hours a with updates unless the architect changes filenames). In other words xrefs, save time 99% of the time.

Now for tabs.
besides the model tab and the first layout tab, which we try to rename to the sheet number
(ex:E-1.0). if we need to revise the sheet and send it out as 8-1/2" x 11" or 11" x 17: sheet to be attached as a adendum item. we cretate a new tab (ex: E-10R1) to show the changes to the drawing with correct title block for the proper size sheet to used in the addendum. On the main sheet (E-1.0) we still put all the revison information in the main title block which is usally the only thing in paper space.

I hope this helps