FLATTEN PROBLEMS - Does anything in AutoCAD work the way it's supposed to?

[Anonymous]

This software is once again becoming extremely frustrating. There are limitations, I know, but a command should do exactly as it is supposed to.

OK, done venting for now.

Here's the problem - I've got a floor plan that has many objects at different Z values throughout the drawing (much to my chagrin after working for countless hours on the plan). So, now my snaps don't work, I turn the drawing and Hello to multiple planes. I check out discussion groups to find a good answer to my quandry. My knight in shining armour is the FLATTEN express command.

Now the fun part.

So I initiate the FLATTEN command, select all visible objects (crossing window), remove hidden lines and step away from my machine for a few to let the command work its magic (it takes a short while to do a whole drawing). When I return, everything seems great. All my objects are now on the Z=0 plane. Back to work, right?

Wrong.

So I begin drawing with my recently flattened drawing and now all my dynamic blocks are dumb. No handles, no attributes, to dynamic properties (blocks that were dynamically rotated amazingly went back to 0). I select one and go into block editor and see that the block is still a fully functioning dynamic block - with attributes - the whole nine. I exit, drawing still represents dumb blocks. Turns out that I needed to reset all the "position Z" values in the blocks to "1.0000" to get my functionality back. OK, disaster averted. Then, I go to snap - my snap settings all disappeared - needed to be all reset (nuissance, but no big deal). Then, (see the trend?) I go to place a block and the Attribute Verify Dialog Box doesn't come up, despite the ATTDIA=1. OK, a little troubleshooting, found the problem (ATTREQ reset itself to value=0).

Now for the one that really bakes my noodle.

Upon further inspection, FLATTEN not only flattened the drawing, but moved and skewed geometry all over the place. I now have disjointed walls, columns that look like the Star of David, toilets that all have their own shapes and walls that look like they have shadows (and they're not supposed to).

Any suggestions before I destroy a perfectly good computer over a piece of defective software?

[Anonymous]

FLATTEN has always done funny things since it came out. Express tools is
(free now) add-on put out by Autodesk but is not supported by them other
then this newsgroup. I've found that if you use "remove hidden lines" it
does what you have described (more). You probably be better off retrieving a
backup copy and trying other methods that are described on these newsgroups
first (on a temp copy).

[Anonymous]

That was such a good post.

But I question: Why can't you just select all and then with your Ctrl+1 Properties menu change the Z properties of respective entities? Select arcs alone because they have a center point. That's how I do it. I still need to find out what that button is for in the status bar.

Also (these notes may be out of date.)
; 1) FLATTEN doesn't support all of AutoCAD's object types. It Works on the following
; types of objects: "3DFACE" "ARC" "ATTDEF" "CIRCLE" "DIMENSION" "ELLIPSE" "HATCH"
; "INSERT" "LINE" "LWPOLYLINE" "MTEXT" "POINT" "POLYLINE" "SOLID" and "TEXT."
; 2) FLATTEN has no idea how to handle application-defined objects, so it leaves ADT
; and similar programs alone.
; 3) FLATTEN doesn't flatten objects nested inside of blocks. (You can explode blocks
; before flattening. Alternatively, you can WBLOCK block definitions to separate
; DWG files, run FLATTEN in each of them, and then use INSERT in the parent drawing
; to update the block definitions. Neither of these methods will flatten existing
; attributes, though.
; 4) FLATTEN flattens objects onto the Z=0 X-Y plane in AutoCAD's World Coordinate
; System (WCS). It doesn't currently support flattening onto other UCS planes.

[Anonymous]

I don't know, but perhaps when you select objects, you don't have to remove
anything, and no select visible objects with crossing. Only, when ask yoy
select objects, print "all" ??? (try this!!)

[Anonymous]

Remember to always work on a copy of your drawing. The advantage is obvious. Include a revision number in the drawing name. Change it every time you close. When you are through with the project delete or zip up all extra drawings. You will always have something to fall back on.

[Anonymous]

Hi, I know this thread is a little old now and there maybe insights elsewhere but just to help those still coming to terms with this great but annoying tool. I’m on 2010 and this is still not resolved.

If you FLATTEN a group of lines and select YES to remove hidden lines your geometry is flattened but will most probably be corrupted - ie rectangles grow or shrink by apparently arbitrary amounts and arcs/ circles split or disappear.

However, select NO to remove hidden lines and your geometry should be fine.

[Anonymous]

What about checking into your OSNAPZ and TREEDEPTH variables?

[Anonymous]

Yes, Flatten it is dangerous, if you check dimensions also will change after the command've been used, try this lsp (found at Cad forum) just to move all your entities to '0', just edit the lsp and change the name for 'flatten' to any name you want, to don't conflict with the express tool flatten comand

[Anonymous]

I used to use the flatten command, but I don't really use it too much anymore. Instead, once you are finished doing what you need to do in the drawings, use AECTOACAD command, and that will save another copy of your drawing, flattened correctly (verify), but if it isn't already, it will at least be much more safe to use the flatten command on the 3D objects.

Flatten is just terrible, in my opinion, because of the things you've described. I've experience these, too.

It took a lot of face-to-keyboard contact before figuring out that you need to use the AECTOACAD command first (I usually just hit [ENTER] until ACAD saves my new, converted drawing in the same path w/ prefix "ACAD-" in front of the original file name), then I open the newly converted drawing, and then I use the flatten command, which will now work as intended.

That's what I always do now. Try that out, and see if that helps!

Also, I don't yet know if this has already been answered, so there was my input, just in case.

[CADmonkey_UK_Building_Services]

Hi, I used to deal with incoming files a lot. Flattening was one of the first orders of business. I have had the good, the bad and the ugly.

Like you, I soon discovered Flatten and its strengths and weaknesses. Don't ever use it on a Block! It also destroys 3D Polylines.

Some tips:

1. If you select the whole drawing, and pull down the Properties pull down where it says something like "all(22343)" you'll see the list of all the different Object Types. Pick one!

Dtext, Mtext, Lines, Circles, Polylines, blocks....once you isolate those, then the Z-insertion points becomes available for each type. It's not as long winded as it sounds.

2. Blocks might be inserted at 0,0, but that doesn't mean that the contents are! One at a time, you can edit the block: open the Block Editor, draw a line from 0,0,0 to your current insertion point, move everything from one Endpoint of that line to the other Endpoint, Copy the Line to the clipboard and delete it. Exit the Block Editor, paste the Line into the drawing anywhere you can see it, select all instance of the redefined block and Move them all from one End of the line to the other. Be careful of your UCS.

3. FILTER command is well worth learning. You can Save filters here and they remain even when you open a new drawing.

4. Save layer states so you can type LAYTHW, LAYON, LAYUNLK before you get busy.

[Anonymous · Accepted solution]

If you want everything at the same Z value:

CHANGE

ALL

P (for Properties)

E (for Elevation)

0

[CADmonkey_UK_Building_Services]

Brilliant!

I used to use that years ago but I stopped because it seemed like Autodesk changed the command in some way so you couldn't avoid opening the Properties Palette. They must have changed it back.

This is a great command for 'clean-up' scripts. Kudos to you!

(PS Maybe 'script' command doesn't work in LT but it's always been simpler to cut'n'paste from a Notepad file into the Command Line.)

[Anonymous]

Fastforward to 2017, and it STILL doesn't work correctly. It's a nightmare importing to Revit, needless to say. 

[Anonymous]

hmmm.... couple of questions ....

If you're working in 3D why do you want to step on all the extra time and intelligence and make it less intelligent 2D??  Use clipping planes, or VIEWBASE (for simple models)

If you're NOT working in 3D, why are you having a 3D issue??

BTW, FLATTEN is not a core function, it's an express tool, which probably hasn't been updated in years.

[RobDraw]

---

@Anonymous wrote:

Fastforward to 2017, and it STILL doesn't work correctly. It's a nightmare importing to Revit, needless to say. 

---

Flatten is not a cure-all for your 3D to 2D woes. Depending on the content of the file, there are usually a couple steps involved.

If you would like some help, start a thread. I'm sure people will help guide you with your specific needs.

BTW, importing into Revit is usually not a good idea.

[Anonymous]

Thank u so much! very useful tips 🙂

[jackshield]

hadnt seen this name in a while ...

[Anonymous]

Hello

What used to work with flatten no longer works in 2016. This is a fact that I know for sure. Used to use flatten all the time. There was a project command that also worked, but does not seem to work the same way.

The only thing that seems to work is to change the Z points of each line. Way to tedious.  When globally selecting the line in properties the pull down only says Varies and does not seem to allow globally projecting Z points to XY. 

Thanks for any links on how to flatten or project onto the XY. 

[Anonymous]

Yup..

For my problem

When I flatten 3d objects.

Everything became 2D but the scale become humongously huge

Like a thousand times larger than the actual scale.

If someone can help me to flatten3d objects normally.

[mnorris843]

i dont even mess with the flatten command. It should flatten EVERYTHING but it doesnt. I selected everything in the drawing using a crossing window. then go through all the properties and change the elevation or z coordinates to 0. Hope this helps.