cut and paste from dwg into sketch problem

[SMB2201]

Hi all, Happy New Year.

I sometimes cut and paste from an AutoCAD dwg into a new Inventor sketch. Most of the time it works and saves heaps of time but occasionally curves in the original dwg are turned inside out when I paste, see attached as seen in AutoCAD environment on the right and when it is pasted into Inventor sketch. Anyone know why it does this and how I can fix it?

Regards
Scott
AutoCAD2008
IV2008SP1

[Anonymous]

1. This can be caused by bad geometry in the original AutoCAD file that
cannot be easily detected.

2. You have imported way too much geometry into one sketch.

If you want advice, post the original ACAD file.
--
Dennis Jeffrey, Autodesk Inventor Certified Expert
Autodesk Manufacturing Implementation Certified Expert.
Instructor/Author/Sr. App Engr. Tel. (260) 399-6615
http://teknigroup.com

[Anonymous]

I looked at your screen shot, and had 2 thoughts. Then I read what Dennis wrote, and low and behold, there were my two thoughts! Dennis nailed, copy in parts of they geometry from ACAD at a time, and you'll have a much better result. And you'll likely see the bad geometry in ACAD as you do this.

[Anonymous]

Actually, i thought I used Spikes... 🙂
--
Dennis Jeffrey, Autodesk Inventor Certified Expert
Autodesk Manufacturing Implementation Certified Expert.
Instructor/Author/Sr. App Engr. Tel. (260) 399-6615
http://teknigroup.com

[SMB2201]

Thanks Dennis, I knew that there was too much geometry so it was probably a bad example. I havent used a 3d package yet that doesnt start to wobble if you use more than four lines, you should see what happens if i forget to take the hatching out! I find though that if I want to bring in a busy sketch (if i was going to model the whole thing as a part instead of an assembly) it only has a hard time with the first paste, after that I create new sketches to create individual "parts" by projecting geometry off the busy sketch and its cool. Having said all that, I have had the same thing happen even when bringing in sketches for individual parts. I have noticed its usually curves (fillets) that turn themselves inside out, ie a line can be tangent to a curve in two spots so sometimes it chooses the other side for some reason. In this case I tried removing all curves but one of the lines still moved during the paste. Continually deleting parts of the sketch does fix it but I am sure due to removing the bad geometry more than the simplification of the sketch. So, disregarding point 2, how can you have bad geometry in AutoCAD? Attached dwg.

[Anonymous]

1. In the AutoCAD file that you posted, I noticed a couple of
interesting things. First, in opening the file in AutoCAD I was
presented with a proxy message. (See attached)

2. all of the geometry in this file was created on layer 0. Why? was
this an exploded block at one time? Was this originally from a solid
model or mechanical desktop file? BTW, there was no geometry on the
other layers within the original file, which leads me to believe that
somehow this was derived from a solid model type file.

3. As shown in the video, when I went to import only selected geometry
rather than all, the very first line that I picked was only a partial
edge line.

Yes, AutoCAD can produce bad geometry, as well as good. If this is a
representative file then you're going to have problems importing it and
others in order to turn it into a valid and simple sketch.


--
Dennis Jeffrey, Autodesk Inventor Certified Expert
Autodesk Manufacturing Implementation Certified Expert.
Instructor/Author/Sr. App Engr. Tel. (260) 399-6615
http://teknigroup.com

[SMB2201]

1. I hadnt considered the proxy graphics issue as this comes up on all their drawings so I turned the message off and hadnt noticed any problems until maybe now.
2. Originally it was created "proper" with solid lines on different layers to hidden, dimensions etc but I shifted them all to layer zero and purged for two reasons, a) to see if that would fix it but it didnt (when you paste into IV it brings them all in as the same line type anyway), b) to make the file smaller for posting.
Creating 2-D from a 3-D file could have some merit as when the Inventor person here eventually gets fed up and leaves, instead of learning Inventor the others simply "save as" an AutoCAD dwg and continue to bastardise that.
3. What do you use for viewing the video?
Excuse my ignoramus but a "partial line"? This also why I put them all on layer 0 and made sure they were all "By Layer" so as to put all lines (I thought) on an equal footing.

Original dwg attached.

Thanks,
Scott
IV2008SP1

[Anonymous]

"3. What do you use for viewing the video?" You have Adobe Flash
player on your system?

The other questions, I'll leave to others to answer.
--
Dennis Jeffrey, Autodesk Inventor Certified Expert
Autodesk Manufacturing Implementation Certified Expert.
Instructor/Author/Sr. App Engr. Tel. (260) 399-6615
http://teknigroup.com

[JDMather]

I didn't bother to look at the dwg, but if you turn off autoconstrain on import it will import exactly as it is in AutoCAD, flawed or not.

[Anonymous]

Dear Scott,

I can not find problems with import. Please, see att. picture.
In ACAD I move the left bottom point of geometry to 0,0,0 in WCS.
I use ACAD and Inventor with all SP and HF.

Happy New Year
Andrey
XP SP3 and HF
AutoCAD2008 (ALL SP&HF)
IV2008 (ALL SP&HF)

[SMB2201]

OK so its my own fault for not bringing it in properly.
I am not actually "importing", I highlight the lines in AC I want, copy (Ctrl+C) and then paste (Ctrl+V) into an open IV sketch so I dont know if Autoconstrain on/off is an option doing it that way.
When I do try importing a dwg all I get is "Sorry, this pre-release product has expired".
Guess I cant complain if I am trying to make it do something its not intended to do, but the 99 times out 100 it works it is handy. Thanks all for your efforts. I think I'll just go away now.

[SMB2201]

Thanks, this did work. I selected about a quarter of the lines and a datum point each time and put them back together in the IV sketch, but I didnt notice any bad geometry as I did it. Well, I think it worked, maybe it just didnt move as much as it did before 🙂

Cheers

[Anonymous]

"Sorry, this pre-release product has expired"

There is a fix for this.... While you are there, download and install
all required service packs and hotfixes for 2008:

http://usa.autodesk.com/adsk/servlet/ps/dl/item?siteID=123112&id=9873900&linkID=9242019


--
Dennis Jeffrey, Autodesk Inventor Certified Expert
Autodesk Manufacturing Implementation Certified Expert.
Instructor/Author/Sr. App Engr. Tel. (260) 399-6615
http://teknigroup.com

[SMB2201]

Thanks Dennis for the link, hot fix and service packs installed.
Successful import of dwg data into a new part.

Roger Dodger Over & Out

Scott
IV2008SP3