Skewed stl files

I have been using Sketchup for several years and never had this problem. I export an stl file, and it gets rotated. No matter what I do, the same thing happens again and again.

When I am done editing my model, and I’m ready to export an stl, it looks like this:

I export the stl, then re-import it, and it looks like this:

It remains like that when I open it in Meshcam to create my g-code.

I’ve tried everything, including rebooting my computer. I cut and paste the model into a new Sketchup window, I import the stl, edit again to straighten it, nothing works.
Its always about 2.4 degrees off on the Z axis, and .3 degrees off on Y.

Can you post the model? Have you repositioned the axis?

WingBottomRight.skp (286.4 KB)
I’ve been using Sketchup 2017, and tried it in the online version. Same results.

And yes, I tried playing around with the axes. Nothing fixes it.

In the original SU file, your axes are significantly displaced and rotated.

In that model, R-click on any axis, and choose Reset.

That will straighten things out.

After axis reset:

Move the corner to the origin, then rotate the model to align a long edge with the red axis.

The lower front long edge is also not parallel to the red axis, either, after I rotate it round the Blue axis, and the component’s axes aren’t parallel to the edges either.
image

Here’s a fixed version saved back to v2017.
WingBottomRight fixed SU 2017.skp (239.7 KB)
WingBottomRight fixed.stl (43.6 KB)
That imports correctly oriented and on the origin.

3 Likes

OK thanks. That works. I’m just mystified as to why it happened in the first place, and to multiple models.

Check whether the template you use to start a new file has got “Reset axes” greyed out. If it hasn’t, R-click/Reset to fix them, re-save the template, and check any existing files based on that template.

As to how it happened, maybe you accidentally R-clicked intending to change a component’s axes, but Placed the model axes instead?

2 Likes

Thanks again for the help. I have that model carving on my CNC machine right now, and I got it perfect thanks to you.

I am having a problem with the stl coming in on a skewed axis for 3d printing in Cura. I can get it within a degree by rotating in cura, but it still isn’t necessarily flat. I set the axis in SketchUp and it’s getting skewed in the export. Any suggestions on how I get it flat in SketchUp and export it so it will drop on the bed in cura? attached are the skp and stl files.

Add multiple ima

ges

[end cap w raft exploded.skp|attachment](upload://ld38hkx1VPcG89q3SiC91LQ3tfN.skp) (5.4 MB) [end cap w raft exploded.stl|attachment](upload://kU5nXPNbHvxbu8oBIG6OgcrYdhO.stl) (54.8 KB)

end cap w raft exploded.stl (54.8 KB)

end cap w raft exploded.skp (5.4 MB)

You have modified the global axis in this model, the axis lines not being square with the horizon is a giveaway. Right click on one of the axis lines (red, green, or blue) and choose reset. Then orient (rotate) your model to be square with the true global axis and re-export.

1

that was quick, thanks. I think I understand now. the axis can be reoriented globally and it can be reoriented within a group or component. I thought I was resetting axis in the group, but it was globally. It worked. I struggled with this for a while. I had read the post and reset the axes globally then the group was skewed. I reset the global axis then oriented the group axis to align the two.

Pat

1 Like

Yes, they are separate, as you have now discovered you can temporarily move the global axis, but not really, the true global axis for the file is unchangeable and always the same (as evidenced by the horizon), and that’s what export uses. Except for specific occasions its best to leave it alone. If you have rotated your object to be square with the global axis then the quickest way to reset the group axis can be to simply explode it and reform the group.

It’s also simple to align any face to the bed in Cura itself. It’s one of the commands on the left side of the screen.
Why did you make a raft in Sketchup? You have an option to do that in Cura with one click…