This would NOT be a bug in SketchUp. When you import the .dxf into SketchUp did you choose the correct units in the Import Options panel?
You can resize the geometry of you know a specific length in the model. Open the imported component for editing. Use the Tape Measure tool and measure the known length making sure to click at both end points. Then type the correct distance and press Enter.
I’m already using the correct units, I have also used some units but the result still same like in the picture
I can’t resize because I don’t know the real size of the surfboard, in software Shape3D is only view the size on Top/Bottom. The DXF file from Shape3D can view the size of the surfboard curve.
Your screenshot indicates that the file uses Millimeters. Your SketchUp screenshot indicates that you have used Inches or even Feet to import. The import unit setting is behind the Options button on the Import File dialog box.
No you don’t. What units are chosen in your Model Info>Units dialog are irrelevant.
Open the Import File dialog. Select DWG/DXF as the file type. Push the Options button.
In the Options dialog, select Millimeters as the unit to be used. This has no connection to the Units dialog. Click OK
This is what I got when I imported using Millimeters. If you find that something is missing, try using a larger unit (Centimeters, Meters) and scaling the result down with the Scale tool. DXF_Import.skp (327.2 KB)
(BTW, My first SketchUp forum question was about this same thing, about 20 years ago. The Options button is well hidden in plain sight.)
First you have to select the file you want to import so SketchUp knows which options to show in the Options panel. Then to Options button will show at the bottom.