While I’ve been around a while, I’ve never before faced needing to import a .dwg file.And while I at least skim every post on this forum, with topics having to do with importing .dwg, I admittedly haven’t paid much attention! So, instead of going over a plethora of topics, I thought I’d ask this forum the specific questions I’d most like answered!
I’m commissioning a survey of a rural property I just purchased. Boundary, topographic, and location of existing buildings, power poles, septic tank and field. The surveyor intends the “deliverable” to be an Autocad DWG file.
Given my vague recollection (from my skimming forum posts) of potential problems importing .dwg files produced by Autocad, I’d really appreciate advice from people here who also work with Autocad - or at least, frequently import .dwg files. What I’d like to know is:
What features of Autocad don’t easily import to SketchUp? I’ll ask the surveyor to avoid using those features.
What should I use for my import settings when I receive the .dwg file?
I’d like to get this right with minimum back and forth with the surveyor. The survey will become a “base map” (ultimately in Layout) which I overlay with plans, as built utility trenches, etc. I’ll also be overlaying it with SketchUp Geolocation overview picture as the overhead imagery is sufficient (with my near real time update) to determine the vegetation and tree density - so I’m EXCLUDING those from the survey (for budgetary reasons).
You know perhaps that text is of no use, it won’t come in. Check out the help sections
The main think I generally need from a surveyor is the contours. But the map of existing features is good too. Just I like to keep the file simple .
Surveys often come in with a TIN 3d terrain, but I find it is better to use their contours with Fredo’s Toposhaper. The TIN usually is cruder. But I often have to clean up the contours in CAD first. Simplifying and checking for cross-overs. But it doesn’t hurt to get the TIN if they are generating it, and you may like it.
Clean up can be done in SketchUP and Toposhaper itself does “clean-up” as well. I’ve just noticed it doesn’t catch if the contours are crossing over, which is a CAD error sometimes.
If your surveyor uses AutoCad Civil or another topo-related add-on he should use the “export to AutoCad” or similar feature to make sure that the file he delivers to you contains only standard AutoCad objects and no special objects that can only be read with the add-on that made them or an “object enabler” in AutoCad.
in general:
• in ACAD: select model space (not paper space)
• opt.: for getting rid of weired attributes or extended ARX objects etc. select everything and ungroup (ACAD: explode) at least once.
• save down to the DWG version 2000 (supports all relevant entity types) by doing a “Save as…”
• opt.: check content with a DWG viewer as free ODA Drawing Explorer or free ADesk DWG TrueView (a stripped down ACAD) which also enables you to save down by yourself
• ask creator for (or assume) the unit used and import in SketchUp accordingly by configuring the used unit (before importing) at “Window > Model Information > Units”
All as Sketchup_3D notes, but I would save back to r14 version of DWG.
No dynamic blocks - or explode them before importing.
All to be simple lines, polylines circles, no complex dlines or other complex geometry