Half shading on face?

I’m exhausted. I get different problems every time I try something new. On the attached, when I make it into a group, it’s solid, so I feel like I’ve done it correctly. But when I click on one of the faces, half of it appears shaded - diagonally from one corner to the opposite corner. As a result, if I try to alter that face, my alteration affects half the face, but not all of it. Very weird. What’s happening?End Cap 10.skp (149.1 KB)

If you turn on hidden geometry you can see the edges that are dividing those faces. Somewhere along the line you move one side out of alignment so the faces had to split.

KEn, turn on Hidden Geometry in the View menu. You’ll be able to see diagonal lines that have been hidden dividing up a couple of the surfaces. I’ve highlighted them in the attached screen shot. How did you make the model?

Box was faster by a nose!

Well now what am I supposed to do with this?


Aw, @Box and @DaveR beat me by mere seconds. I was just about to post my screenshot and explanation, hehe! This community is really good and caring. Good job guys! Maybe I’ll have better luck next time.

Several of the edges are out of alignment. For example, the edges of the top surface are not parallel (draw a rectangle on it from corner to corner and then zoom in close, or label the vertices with their coordinates). I don’t know what process you followed to construct this model, but it appears that at some stage you either didn’t pay close attention to inferences or dragged something slightly askew. The misalignments forced SketchUp to split those faces because they are not planar.

Thank you all for the pointers. But I don’t know how to correct it. Dave - I drew it from scratch trying to duplicate the part we worked on yesterday, but elongated by about 1/8". I see now that every time I start working, my specs go back to default (architectural, 1/16", etc) That’s kind of a pain, but now I’ll look every time I start up.

This is a great group. Doesn’t anyone sleep? :grin:

Set up a blank model with all the settings you want and purge it. Then Save as Template and make it your default.

Sleep, it’s early afternoon for me.

Good idea! And, I redrew the model and now it’s fine. Work work work… Thank you!

Luckily the world is round and there is only one sun.

Wow… @Box @DaveR @Gully_Foyle @slbaumgartner

This was like a SketchUp Sage quick draw match…

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What I think is strange, or at least improbable, is how similar are the views framed by Box and DaveR.


He copied me. :smiley: :smiley: :smiley:

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So I figured out that when that arc follows around the curves and the inside is rectangular, I get a lot of instances that have to be deleted. And, why is it that when I use the two point arc, the curves are very smooth? Much smoother than using the circle tool at 48 segments.

Could you explain more, or better, upload an example? I don’t understand what you are saying…instances of what?

I don’t see the effect you describe. An arc and a circle using the same number of segments per degree (e.g. 12 for a 90 degree arc and 48 for a full circle) use exactly the same geometry. There should be no difference in appearance. Again, can you upload an example that shows what you mean?

Ken, depending on the exact profile, the width and the radius of the curves in the path, you can end up with some excess geometry in the corners as you do with the rounded bottom on your plug. If the radius of the corners of the path were larger, you wouldn’t get the excess geometry. Doing the intersect faces step and erasing the edges will take care of those extra bits of geometry.

As for the arcs and the circles, I’m guessing you’re seeing the exploded edges on the small circles but the 12-segment arcs with their longer segments aren’t exploded so those surfaces appear smoother. Soften those edges and you’ll see the surfaces do appear to be smoother with the larger number of sides.

Check your PMs.


Here’s more on the extra edges and faces. I took the model we worked with the other day and got rid of the rounded bottom so it is back to the stage before running Follow Me with the round over profile. The profile is getting swept around the outside of the shape. Suppose the extrusion is from left to right around the arc. The profile gets extruded slightly beyond the inside corner before it starts around the curve so you get some additional lines on inside. Then on the transition from the arc to the straight line on the right, the same thing happens so there’s another bit of excess geometry created. As I mentioned before if the radius of the arc was the same as the wall thickness, this wouldn’t happen. You could think of it as the profile could then pivot around the inside corner.

sl - Here’s an upload on the smooth corners I mentioned. I’ll try to show the inside corners of the Follow Me piece later if I have time.

End Cap 13.skp (178.4 KB)

As you can see, one corner is jagged like the ones above it whereas the other three appear smooth.

And, why is it that every time I draw a circle I need to input the 48 segment spec. It doesn’t hang on to it.

Dave - the radius is the same dimension as the wall thickness. But I seem to get overlap in the inside corners. Weird.