V4 Import STL circle size error

[ve3sjk]

I have an stl exported from Sketchup that has a diameter of 508mm

When i bring it into Simplify 3d version 4 and click on the model file to get dimensions it shows 508mm in the X size but only 507.69 in the Y size direction.

Untitled picture.png (5.99 KiB) Viewed 164 times

Would this not mean that i would not be printing a true circle?

I can scale it independantly to get it right, but I would think that a circle at 508mm would be 508mm under both x and y.

Can anyone explain why it would give me a smaller dimension in the Y axis for a circle?

Horizontal size is turned off in the slicer and this works out to a 0.06 percent scaling error in the Y-axis.

I have attached the stl I am loading into the software.

[parallyze]

I have an stl exported from Sketchup that has a diameter of 508mm
Can anyone explain why it would give me a smaller dimension in the Y axis for a circle?

Because depending on the quality settings your objects will be segmented. There's no arcs
or circles inside STL files.

Horizontal size is turned off in the slicer and this works out to a 0.06 percent scaling error in the Y-axis.

...I highly recommend checking out what horizontal size compensation is for.

I have attached the stl I am loading into the software.

Seems fine. S3D will tell you the size of the bounding box. And that's 508.0 x 507.69 because
of the segmentation: