I have downloaded a simple drawing as a DXF file to use on a laser cutter. My problem is that the components in the downloaded file are not the correct size.
When I inputted the DXF file back to Sketchup all the objects are bigger than their original version.
What version of Sketchup are you using? Your profile indicates SketchUp Free which doesn’t have the ability to import or export .dxf files.
Are you exporting a .dxf file? Do you have the camera set up correctly? Share your .skp file so we can see what you are working with.
When importing, check in the import options that your import units are the same that have been used to create the DXF file.
I purchased Sketchup for Web specifically for this purpose. This makes my inability to use the system successfully particularly galling.
Roger
Anssi
I cannot see where you do this. When I expost to DXF the Full Scale option is greyed out but I specify
In Drawing
1.0 cm
In Model
1.0 cm
When I import the resulting file back, I specify cm
Scale
Units
the same as the original.
Roger
So SketchUp Shop, not SketchUp Free? Please correct your profile.
So we can help you sort out the problem if you want. Upload the associated SketchUp and .dxf files so we can see what you’ve got going on. I expect the fix is simple enough.
A 2D view must use Parallel Projection and a standard view to be able to be to scale. 3D model is always to full scale. A perspective view cannot be to scale.
Thanks. I’ll try that.
I have tried that. I initially thought it had solved the problem as when I imported the DXF version back into Sketchup it was the same size as the original. However, when I downloaded the DXF file to the laser cutter over the weekend, the output was the wrong size (12mm x 3mm) rather than 31 x 8.
I’m at a loss for an answer; could it be Sketchup is using inches and the laser cutter mms?
I’ve tried using the 3D option of the DXF file and I thought that had solved the problem but I found out at the weekend that it had not. I’ve attached the files
quilting - house template.dxf (1.3 MB)
quilting - house template.skp (128.1 KB)
Thanks for your help
Roger
Your .skp file shows the overall length at 12.327 inches long. When I import your .dxf using inches as the import units, I get the same. 12.327 inches translates to 313.105mm. The fact you are getting 12mm indicates you exported this file using inches and imported it to the laser in millimeters. You either need to change the units in SketchUp to millimeters before exporting or you need to change the import units on your laser to inches. If you want the thing to be 31mm long instead of 313.105mm as you’ve modeled it, you also need to scale it down in SketchUp.
Your .skp file:
Your .dxf imported into SketchUp:
Imported into LayOut:
And imported into LibreCAD.
I think you could be right. Hopefully on Wednesday when I will be able to use the laser cutter again will provide concrete evidence.
I couldn’t see any way of converted in the units in Sketchup for Web. (I had to move it to the old, free version of the app to achieve the change to mms.)
Here’s hoping.
Many thanks
No, I’m a glass half-full type of guy. 
I couldn’t find Model Info. I tried searching for various terms, such as millimeters, convert, units with no success.
You don’t see the i in the circle below the eye glasses icon over on the right?
I hate to a pain but I’m still having problems. When I import the DXF file to the laser cutter additional lines appear on some diagonals. These additional lines doe not appear if I import the DXF file back to Sketchup bu do appear when I load the file into the CAD, DXF, DWG Viewer for Google Drive.
I have attached the original Sketchup file, the DXF version created by Sketchup and how it appears in the viewer
20220401.skp (144.4 KB)
.
20220401.dxf (612.0 KB)
Thanks for your help.
Rpger
What happens if you set the Camera to Parallel Projection instead of leaving it set to Perspective?
See this from last week.
Your model is set up this way with the Camera set to Perspective. First clue is the blue axis is visible in the Top view. You can also see that Perspective is chosen in the Scenes panel.
Parallel Projection. No visible blue axis.
I think I’ve made that change but there are still additional lines.
20220401 (1).skp (143.5 KB)
Roger
Being in perspective or parallel projection doesn’t basically matter if you are exporting “3D”, but someone opening it in CAD may be confused if it opens in a perspective view.
The triangles probably come from the limitations of the receiving software in depicting faces. I don’t see them in Autodesk TrueView but they show up in Rhino. I don’t know anything about lased cutting, but are the faces needed? Looking at the files discussed here previously, most people exporting for cutting etc. export only the edge loops.
I am not an enormous Autodesk fan, but when it comes to DWG and DXF compatibility I tend to trust them more than other parties. There is no Trueview for the Mac, but Autodesk has an online viewer at https://viewer.autodesk.com
Thanks
I’ll try that.
Roger
