Please tell me why this happens



I am creating a simple model.
Can you see the image clearly?
Sometimes diagonal lines appear on the model.
What is the cause of this?
Thank you in advance.

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Errors in the way it was drawn, the faces are not coplanar.

Also, go to Window > Model Info > Units and uncheck ‘Enable length snapping’


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!! 同一平面上に作成していると思っていました。モデルを確認してみます

!! I thought it was created on the same plane. Let’s check the model.

I have the impression that you’re drawing from a CAD plan, and this may be the reason if it’s badly done.

Go to Styles > Edit > Colors > By Axis, to see if the lines in your plan are aligned correctly.



I unchecked it. What effect does unchecking it have?

This option adapts what you draw to the nearest unit. Deactivating it allows you to draw freely, without constraints. But you won’t need it here, I don’t know why he suggested you disable this option.

I suggest you go to Styles > Edit > Colors > By Axis to check that the base of your plan is properly drawn. I’m willing to bet that’s where it comes from (I often receive poorly drawn plans).

Not necessarily.

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It could help you in the future to avoid a certain type of error. But the way you draw remains the basis.

Create the 3D model using the 2D plan only as a general reference, do not rely on it as it can be poorly drawn.

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You need to go to edge editing (the little cube on the far left).

Yes, I agree on this one, but it’s always a good idea to start there. Here, I have the impression that his mistake comes from the fact that the two walls on either side of the opening are not aligned.

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I see. Thank you!
I am still searching.
Please give me your time.
Go to Styles > Edit > Colors > By Axis, to see if the lines in your plan are aligned correctly.

I am still searching.
Please give me your time.

Precisely because there are situations like these, using that style creates a false impression of correctness/security and deceives a beginner in the way he draws. Especially since he doesn’t know it’s wrong.
There are other examples in the forum with such situations.


Don’t rely on the ‘Color by axes’ style!

I’m not sure I understand what you’re saying, but I think I agree with you anyway.

I’m just saying that you can only trust yourself, and so whenever I receive a CAD drawing that I haven’t drawn, I always start by checking it by displaying the edges by axis. In 90% of cases, I find mistakes, correct them, and this allows me to start modeling on a correct basis.

If it works for you, it’s ok!

I’ve been using SketchUp for a long time, but I’ve never solved this problem.
I’d like to thank the two of you for asking this question and letting me know so quickly.
Thank you very much.

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