Fix dimensions of imported SVG?

[Anonymous]

Hi all, I'm a brand-new CAD user trying to figure out some basic product design. I am familiar with drawing/illustration apps but have not yet conquered even the basic sketching in Fusion 360 to create the shapes I need (I'll get there eventually). In the meantime, I've tried importing an SVG of my design. In my drawing program (Affinity Designer for Mac) the dimensions are correct. They print at the correct measurement. But when I bring the SVG into Fusion 360, the dimensions are not accurate. Far from accurate, in fact. Is it possible to select a segment of the SVG drawing and tell Fusion "this line is supposed to be XX inches" so that it will scale the entire SVG to the correct size? I have not found a way to do this, and it would be extremely helpful if I could.

Thanks!

BTW, the YouTube videos by Lars Christensen are fantastic. He's really helping me understand the overall function of Fusion in ways that other videos I have watched have not. Everything is still way over my head, but I finally feel like I'm making some progress.

[James.Youmatz · Accepted solution]

Hi @Anonymous,

Welcome to the Fusion 360 Community!

Theres a few ways we can do this. The first is to scale the entire SVG file upon import. After you import the SVG file, there is an option to scale. You can use the Measurement tool from the Inspect menu to see what scale factor your SVG needs. If you want to share the SVG file with me (and some units) I can go ahead and show you this.

The other way you can do this (although it won't scale the entire sketch and will need constraints added) is to dimension each line of your SVG file. If you insert the SVG and press OK, you are automatically now editing the SVG in Sketch mode (as it has now become a sketch). You will notice these lines are green since they are fixed and cannot be edited. If you window select all the entities of the SVG so they are highlighted and right-click you will see an option for Fix/Unfix. Click this and the green lines will turn to blue. Now, you can use the tools in the Sketch menu (such as sketch dimension) to add dimensions to lines. As mentioned though, for the fully model to behave correctly - you will need to add sketch constraints to the model if you plan on using it this way. You can also scale the entire sketch by going to the Sketch menu and selecting Scale.

Thanks,

[Anonymous]

Ah, so based on your explanation it appears Fusion 360 can't automatically scale the entire SVG to the correct size based on the user-input dimension of a single line? If not, that would be a very helpful feature to add in a future update.

In my case I can't add specific dimensions for every line in the drawing as my drawing app does not feature a measuring tool. I would have to go into the drawing app and basically trace my entire drawing line-by-line to get the exact dimensions of each individual line. Not a great option.

For now I will use your first suggestion and hand-calculate the necessary scale factor by comparing the original length of a single line in my drawing to the length shown in Fusion after SVG import. Hopefully the Fusion team will consider making this process simpler in future updates.

Thanks so much for your help!

[drjohnsnKT63F]

This conversation is a bit dated, but I was searching for a solution myself.

With Affinity Designer, you have the ability to change the resolution of the file. This initially makes little sense, given the resolution independent nature of vector graphics, but proves incredibly useful when designing for print or screen or, indeed, CAM.

Fusion 360 assumes 96 dpi. If you change the Affinity Designer document to 96 dpi, it will import as desired.

[iSuat]

Thanks

[tralfazy]

Fusion 360 imports SVGs at 96 dpi while Adobe illustrator saves SVGs at 72 dpi.  Import SVGs from AI using a scale factor of 1.333 and the dimensions will be correct. 

72 * 1.333 = 96

[tralfazy]

This is an old thread but for someone who is trying to fix this now, I am posting information from what I learned about it...

Fusion 360 imports SVGs at 96 dpi.  A.I. saves SVGs at 72 dpi (rediculous!)  No monitor uses that low of dpi since the 1980s!  Neither app lets you change that setting.   (at least not on my old version of A.I)

That throws off the measurement scale in A.I. for just about everybody.

If you are importing SVGs into Fusion from A.I. set the scale factor at 1.333

72 * 1.333 = 96

For Inkscape .9x set Document Properties --> Scale 3.77953 units per mm.  Save it as your default.svg

For newer Inkscape 1.2 set Document Properties --> Scale 2.64583 units per mm.  File->Save Template, set it as your default template and give it any name.

For other apps that export SVGs, change the dpi to 96 for use in Fusion 360, otherwise you probably need to scale it coming in to Fusion at 1.333 if they are also using 72 dpi in their output scaling.

[sjweir76]

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@tralfazy wrote:

This is an old thread but for someone who is trying to fix this now, I am posting information from what I learned about it...

Fusion 360 imports SVGs at 96 dpi.  A.I. saves SVGs at 72 dpi (rediculous!)  No monitor uses that low of dpi since the 1980s!  Neither app lets you change that setting.   (at least not on my old version of A.I)

That throws off the measurement scale in A.I. for just about everybody.

If you are importing SVGs into Fusion from A.I. set the scale factor at 1.333

72 * 1.333 = 96

For Inkscape .9x set Document Properties --> Scale 3.77953 units per mm.  Save it as your default.svg

For newer Inkscape 1.2 set Document Properties --> Scale 2.64583 units per mm.  File->Save Template, set it as your default template and give it any name.

For other apps that export SVGs, change the dpi to 96 for use in Fusion 360, otherwise you probably need to scale it coming in to Fusion at 1.333 if they are also using 72 dpi in their output scaling.

---

Thank you, I found this very helpful. Not sure if it was a typo but, I had to set it to 0.264583 for the newest Inkscape 1.2

[bedmonson85]

@sjweir76 

"Thank you, I found this very helpful. Not sure if it was a typo but, I had to set it to 0.264583 for the newest Inkscape 1.2"

This (0.264583) worked for me in the latest version of Inkscape (v1.3).

Thank you so much for clarifying this... this scaling issue has been driving me crazy for months! 

[emilyortoneco]

Thank you! The scale factor for importing svgs from inkscape .9x was exactly what I was looking for

[bbaley]

For whatever reason, in my Inkscape, version 1.3, I had to use the following instead;

0.2585857853324514 per mm
0..010181 per in

Not sure why the difference.

[william_staceyT]

Thanks. That worked for some other SVG I am using. Worked.

[fabien.huetYMNAA]

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@tralfazy wrote:

Fusion 360 imports SVGs at 96 dpi.  A.I. saves SVGs at 72 dpi (rediculous!)  No monitor uses that low of dpi since the 1980s!  Neither app lets you change that setting.   (at least not on my old version of A.I)

That throws off the measurement scale in A.I. for just about everybody.

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The ridiculous part is to look the the dpi. This is massively stupid. Dpis are for raster graphics. SVG are vectors.

In the svg, if the drawing puts a point a the coordinates 1mm,1mm, why would you want to put it anywhere else that at the 1,1 location? This is absurd. Thanks for the lost time.

[swolfington]

If you're coming from Inkscape, I've found that exporting as .DXF (and making sure setting the base unit to match your document) will import 1:1 into Fusion. I'm not sure why they are making scale assumptions based on DPI when importing SVG (if Autodesk is listening, please fix this, or at least let us specify a DPI on import), but at least with .DXF it seems to respect the declared units in the file.