Corrupt DWG exports from REVIT?

Hi all, I have a problem with a laggy autocad file that has been created from revit. Basically, what I have done is exported the revit title block to autocad so I can use it in dwg’s, hence keeping all of our drawings looking the same across the project. A little further down the line I have noticed a few anomalies when working on this revit-born dwg…

Firstly, the smallest (but most annoying!) thing is that when working on the drawing, selecting and deselecting ANYTHING will result in a half second lag. The program simply freezes for half a second.

Secondly, I notice that snaps are hindered, cad not recognising intersections and endpoints etc showing that ‘fragmented’ looking icon you see when snapping at a funny angle in 3D. Flattening does not vet this problem either. I picked up a lisp some time ago that takes a more forceful approach to flattening, which worked at first but then two days later the problem recurred, obviously where I had added to the drawing.

Thirdly, I duplicated this cad file and worked on them both for a period of time, then tried copying & pasting at 0,0 world coordinates from one drg to another only to find the copied items disappear! Deleted absolutely everything in one of the files, re-pasted and zoomed all in a bid to find the lines but still nothing until I use qselect to indirectly select them.

Purge, -purge, Audit & Recover all seem to be ineffective in solving this problem so i thought I would post it on here and see if anyone else has come across a similar scenario?

So much for a happy new year!

Wow, quite the dust up you created there.

Re: Snaps. Have you enabled the Dynamic UCS feature?

Are you sure all your geometry has a "Z" of "0"?

Are there xrefs involved?

You don't have Snap enabled do you?

Haha, Revit started it…

I wasn’t familiar with this setting, but looked into it and the parameters within seem to be enabled in my favour already (I’m using Revit & Acad 2013 by the way, my account’s outdated). Are you thinking there could be some behind the scenes coordinate arrangement that’s bugging my drawings out?

Why would you have Dynamic UCS enabled if everything now is 2D and flat?

Can you post a copy of the drawing?

Try exporting to an earlier version of .dwg to simplify the file a bit.

A title block should not have anything 3D in it, unless it's a keyplan or something. Are there any hatches or custom fonts? Check the text items. When Revit exports, the formatting is done in the MText editor. You may need to create text styles and remove that formatting.

Thanks for the interest guys!

Remark,

As I say I’ve not had any experience with dynamic UCS and so on discovering it this is what was the default. Toggling around with it doesn’t return any immediate results though… I’ve posted the offending file stripped down to just two lines and you’ll notice the deselect lag mentioned earlier (albeit it seems a little shorter now I’ve stripped file size right down). A flatten cures the snap problem, though if you work on the file for a couple of days the problem returns. I can’t seem to reproduce the copy/ paste to 0,0 scenario, this seems less persistent than the other two.

Rob,

Interesting, I saved down to ver. 2000 without a hitch, but saving to R14 crashes CAD every time? There’s only two lines in the drawing, of which have been Wblocked from my working file so there shouldn’t be any clutter in there.

Oh and mentioning the text, we did have the standard arial revit text at first, and it did start showing up slightly differently as it got copied around the drawing (ie some texts seemed slightly thinner than others, albeit they were all created from the same text box)… That was early doors though and it was soon deleted and purged out.

Edit: Can't seem to get the drawing uploaded?! Keep getting a popup telling me that 'The following errors occurred: new block.dwg: Upload of file failed.'.

Tried at work thinking it was choppy internet/ restriction etc but now at home and still no luck... Am I missing something?

I was trying to suggest that when you export it from Revit that you could try having Revit save it to an earlier version to see if that helps. Alternatively, you could try converting the .dwg to an early version using Drawing TrueView.

Ahh I see. That could do the trick I guess, though my drawings have now been created and any copying/ wblocking etc. only transfers the problem to whichever drawing it ends up in!

Oh and by looking at it dwg trueview only converts back to version 2000, which I managed in ACAD anyway...

Something that popped into my head (not a real solution but hey) - if things really got bad I could export to dwf, then convert back to dwg again xD. Did that some time ago on another project for an unrelated problem and it vanished for good! Haha cheap and dirty one that

Doing a SAVE AS is not the same as exporting or converting.

Whoops! A slur on my words there. I meant to say that I converted it down to 2000 in acad

We can tell the difference between your posts and ours just by looking at your screen name. Is the light blue smaller text necessary?

Really? It must be slow in your world today or you got a bug in you coffee. Pretty petty to comment on that, even for your standards.

Ahh poor form!! My bad chaps - wasn't trying to make a statement with the blue, just a straight snip from my outlook so formatting must have remained.

Incidentally, I sussed the upload problem – Wblocking just two lines creates a 3.5 megabyte file?!?!?! The upload limit’s only 1mb

Don't worry about it. I don't think there are any rules about formatting you posts. Remark is just very critical. Often to the point of being inane.

If you had used hot pink and made it extremely large, then there would be justification for comments about your choice.

Hi all, I have a problem with a laggy autocad file that has been created from revit. Basically, what I have done is exported the revit title block to autocad so I can use it in dwg’s, hence keeping all of our drawings looking the same across the project. A little further down the line I have noticed a few anomalies when working on this revit-born dwg…

Firstly, the smallest (but most annoying!) thing is that when working on the drawing, selecting and deselecting ANYTHING will result in a half second lag. The program simply freezes for half a second.

Secondly, I notice that snaps are hindered, cad not recognising intersections and endpoints etc showing that ‘fragmented’ looking icon you see when snapping at a funny angle in 3D. Flattening does not vet this problem either. I picked up a lisp some time ago that takes a more forceful approach to flattening, which worked at first but then two days later the problem recurred, obviously where I had added to the drawing.

Thirdly, I duplicated this cad file and worked on them both for a period of time, then tried copying & pasting at 0,0 world coordinates from one drg to another only to find the copied items disappear! Deleted absolutely everything in one of the files, re-pasted and zoomed all in a bid to find the lines but still nothing until I use qselect to indirectly select them.

Purge, -purge, Audit & Recover all seem to be ineffective in solving this problem so i thought I would post it on here and see if anyone else has come across a similar scenario?

So much for a happy new year!

Have you tried Overkll as well?

I thought I put it nicely.

Yes, I find the color and size of the text difficult to read.

Tried overkilling also, no luck!

I’ve managed to spend some more time on this today, and thankfully now I think I know where the problems are coming from…

If you open up a fresh acad template drawing and go to purge it, but instead of doing so go to the ‘view items you cannot purge’ dialogue, it will show you a few of the elements you can’t remove. Not a lot though right? Well, in my wblocked file consisting of one 500mm long line on layer 0 (the only layer) I have a HOARD blocks and line types lurking in there! Now, I tried copying this one line into a fresh one. I do this and all the hidden blocks and linetypes come along for the ride! How on earth is this happening?

I can see the problem now, just no means to fix it…

NB: Before the file was wblocking to 3mb, but after xreffing it into a new drawing, using the in-place xref editor and then the ‘remove from working set’ button to extract that one line from the file it seems to be wblocking to about 1mb. Another unexplained quirk! I’ve managed to get the offending file uploaded now thanks to that though. ---> new block.dwg

I got your file size down to 53KB. Maybe you should hire a cleaning service. I recommend Maids-for-a-Day.

It took me a couple of tries to crack the file but when I finally ran the command line version of Purge on it the result was 1174 unreferenced linetypes were deleted. Then when I ran an Audit on the file it turned up 12,322 errors. No wonder why it came in at a file size close to 1MB.

"-exporttoautocad" in acad -> 52kB

then http://www.theswamp.org/index.php?topic=43362.0 -> 48kB

Thats what I do with every revit,mep,archi,... .dwg

Be careful^^