Question regarding dwg file import and edit
-
Hello,
I am a beginner of sketchup. I tried to import a dwg file into sketchup, but I got some problems.
Since the imported drawings are in a group, I exploded the group by right click. Some lines are broken into pieces. I planned to make 3d model by a imported 2d dwg file, but the selected lines cannot be extruded by the push/pull function, no matter I made the lines into a group or not.
My questions:
1, Should I do something before editing the 2d drawing? And how can I extrude the 2d imported drawing by push/pull?
2, How to avoid the lines broken after importing dwg file?Thanks a lot!
William
-
When you import the DWG and there is preexisting geometry it comes in as a component [older versions made it a group] you can edit its contents by double-clicking it: there's no need to explode it. If the model is empty then you can group what is imported...
Assuming the CAD information is just lines then it will never 'extrude' using the native tools; e.g. PushPull works on Faces.
Edges [aka Lines] that form continuous coplanar loops will take a face if you draw over one of the edges with the native Line-tool. Sometimes if the outline loop is complex you might need to draw a 'diagonal', which can then be erased after the faces form.
Use a Style that distinguishes profiles as thicker and shows end-points - this helps see what needs fixing.
Many CAD drawings are sloppily made and you might find small gaps in a loop of edges that mean no face can be made ['profile' thickness edges], sometimes this can be fixed by drawing the adding pieces...
Sometimes the CAD-lines are not coplanar and can therefore never form a single face.
There are some scripts to 'flatten' lines to z=0 [there are AutoLisp tools to do this too].
There are also some scripts to add faces to selected edges which can automate at least some of the effort.
It is often recommended that you use the CAD import as an underlay and draw rectangles over the main shapes, these are guaranteed to be coplanar and combined with the Offset, Line and Erase tools you can quickly recreate a quality SKP equivalent to the CAD plan - usually better and faster than messing on with the CAD lines themselves...
See this http://www.youtube.com/watch?v=MtqJh-DUG30 for some tips... There are many similar videos too... -
@tig said:It is often recommended that you use the CAD import as an underlay and draw rectangles over the main shapes, these are guaranteed to be coplanar and combined with the Offset, Line and Erase tools you can quickly recreate a quality SKP equivalent to the CAD plan - usually better and faster than messing on with the CAD lines themselves...
TIG-- I often find that the above is true (though sometimes other users and some instances of my own imports argue otherwise).
There's so much to say on this, and usually you have the best info. (don't use ACAD myself but you have a full explanation on that end). It would be great for everyone if this were codified somehow as some sort of Sketchucation resource.
Peter
-
Certainly an organic shaped carparking layout from CAD, for example, will not be readily 'fixed' by using SKP rectangles - these suit building plans quite well though - for free-formms using the Make-Faces-tool approach, or the Sandbox-Drape-tool onto a sigle large flat rectangular face can do the job: although these shapes are even more likely to have sloppy CAD techniques in them... as you will have see from recent a thread, if the CAD file is full of poo, then many hurdles appear and bugsplats can ensue... in that recent case there were three lines only 0.002" long... and unsurprisingly these and a few other things caused issues... There are tools [see thomthom et al] that help sort this kind of thing too...
-
Thanks A LOT for TIG and Peter's quick reply and response. I really appreciate your patient help!!
-
Does this belong under "bugs"?
It doesn't seem so to me. -
I'll move it into Newbies...
I didn't notice the parent forum
Advertisement