SketchUp DWG/DXF Export Options Issue

[a.tennant1]

Hi there,

I’m trying to export my SketchUp Pro 2024 file to a DWG. I have set the view for the model to parallel projection and the ISO view.

When I’ve viewed the exported DWG in AutoCAD 2025, I’ve noticed that the dimensions are off by about 20%, and after a bit of online research I found changing the Export Options to have Full Scale 1:1 ticked would solve this issue and export the model to scale.

I click File, Export, 2D Graphic, and choose AutoCAD .dwg. When I go into Options, and make my changes to have Full Scale ticked, then press OK, the export scale is still off by 20%.

I tested this, and If i make the changes in options and then press OK, then press options again to view my changes immediately, the options have reverted back to what they were before I made my changes.

I’ve tried running SketchUp 2024 as an administrator, and have freshly installed 2024 (I was using 2023 before), but the issue is still persisting.

Any help with this is much appreciated.

[Anssi]

@a.tennant1

I have set the view for the model to parallel projection and the ISO view.

@a.tennant1

I click File, Export, 2D Graphic, and choose AutoCAD .dwg. When I go into Options, and make my changes to have Full Scale ticked, then press OK, the export scale is still off by 20%.

2D image exports to DWG are accurate, but along the picture plane. Edges and objects that are not parallel to the picture plane are naturally foreshortened. For an ISO view, you can calculate the scale to use for the export to get lines that are parallel to the SketchUp axis to be to full scale but anything that has another angle still will be off.
Is this the time of the year that first-year students are given the ISO drawing assignment? The same question was asked a couple of days ago. School assignments are the only thing ISO annd other parallel projections are used today.

[ateliernab]

@Anssi

Is this the time of the year that first-year students are given the ISO drawing assignment? The same question was asked a couple of days ago. School assignments are the only thing ISO annd other parallel projections are used today.

probably, I remember drawing my first axonometries during stormy autumn nights.

@a.tennant1 see my answer in the other thread, withe explanations and solutions

Dimensions change when exporting as .dwg

there is. you’ve already found it. an isometry deforms the model so the 3 axis are now 120° appart. And often, to avoid visual deformation (the thing looks bigger than it actually is), a scaling is applied. A standard ratio is √(2/3) so about 0,816. looking at the dimensions in your DWG, that’s the case with sketchup. you could probably try scaling up by √(2/3) before hand to test. Turns out another architect student (back then at least) had the same question, and she came up with an extens…

[Anssi]

To get a “full scale” ISO drawing use this setting when exporting:

My old pocket calculator gave 1224.744843 as the scale but the dialog doesn’t display the decimals.

@Anssi

School assignments are the only thing ISO annd other parallel projections are used today.

In my student days I used to be a great fan of James Stirling so I drew quite a lot of axonometric views but that was before the personal computer revolution.

[a.tennant1]

Hi there,

I’ve tried ticking this option so that it exports it at a 1:1 scale, but if I press OK and then click back on options to view my changes again, the changes have disappeared and the settings are back to what they were before. It’s like the options are not being saved when I’m pressing OK.

Thanks for your help by the way, really appreciate it.