Extrusions and Drawn Lines are not snapping to UCS



This happens to me just about every time I’m working on a model after a few days into it, without fail. Say I create a window frame; there are many many ways to go about creating a window frame-like object, but let’s I do it this way… I start with a 3" x 1" rectangular plane and extrude it 3’. I then copy an end-line back towards to origin 1" creating another rectangular plane on top of our extruded box. I extrude that plane up 3’. This gives us a 3’ long by 3’ wide “L” shape… All the while maintaining orthagonality with the UCS snaps. You can see where I am going with this…

The issue: When I am extruding the last plane downwards to complete the last side of my window-frame the planes don’t match up. They are off! They are off by less than 1/64" of an inch but nonetheless they are off. They are off by enough that for the rest of the time I’m building this model I have 2 snap-points that are almost indistinguishable from each other. Two snap points for planes to build from. Two snap points that leave me ripping my hair out because planes that SHOULD be appearing are not.

This doesn’t just happen with extrusions either. I’ll run a line along a UCS guide 25’ and the line will be not follow. It will appear to follow, but when you measure to a supposedly parallel line, they are not parallel. It makes creating a complex model nearly impossible.



How about uploading an example SKP file showing the issue.

I read your description several times and it just sounds like you’re working way to hard to wind up with what you say you are drawing. It also sounds like you have several points where it would be easy to introduce errors.


Unfortunately the file is proprietary. And I agree that I am working too hard on it, lol…

I apologize if I didn’t explain clearly, but the problem arises not just when making objects like I described, but when extruding any object this happens.

Say I have a wall, 1’ thick, 30’ long and 10’ tall and I want to taper the top. Say I draw a triangle along one side with the angle I desire, then extrude that triangle 30’ along the top of the wall… The second extrusion will not be parallel with the wall. By the time it gets to the other side the extruded triangle will be 1/64" to 1/32" below the line it should be coincident with.


I’ve been using SketchUp since 2003 and the only time I’ve ever seen that sort of thing is when faces aren’t square to begin with. I’ve never seen Push/Pull do anything but extrude in the normal to the face being acted on.

Surely if this happens to you, you can make an example file that shows it.


I’ll see if I can pull something from the file I’m working on…


And yes, you’re right, the only time I’ve seen this happen is when the
plane isn’t straight to begin with. Yet they should be straight according
to the UCS guides, hence the infuriation.


Well, I figured it out. Operator error.

There was an object that I was using as a basepoint that somehow became
skewed… Embarrassing.

Thank you for the help though!


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