Why is an exact square only "~2ft" when I made it exactly 2ft?

I’ve lately been running into a bizarre issue where SU seems to be displaying “approximate” (tilde) measurements for exact whole length sizes. For example, if I draw a 2ft x 2ft square (typing the measurements in exactly) and then use the tape measure tool to measure the width, it then shows me the width is “approximately” 2ft.

Screenshot 2021-03-23 080918

I’ve played with a bunch of different Model Info settings and still can’t seem to find a way to make that measure “exactly” 2 feet. What am I missing here?

Screenshot 2021-03-23 080934

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Disable length snapping to start with.

Can you attach your model so we can check it.

I’m not seeing what you are. As Box instructed, turn off Length Snapping. It wouldn’t hurt to increase Display Precision, too.

Here, with Length Snapping off.

@Box Here is the model with a 2’x2’ square added toward the middle of the screen (reverse faced). Appreciate the help!

Sketchup_Upload.skp (514.1 KB)

When I run the tape measure tool from one side to the other, I get “~2’”

You have display precision set to 0" and the square is 1/64th off.

If I type 2’x2’ in the measurements box, how can the square be anything other than that measurement? Also what does Display Precision throw off specifically in this case?

Why did you set Display Precision lower? If You set it higher, you’ll get a more precise display of your dimensions. Display Precision is just that.

Here’s what I get when I draw a 2’ square.

Found the problem. I think.
You have changed the axis and it is very slightly off.

You can see here just resetting the axis removes the tilde.

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For the floor plan yes, but I can’t yet see this for the little rectangle.(**)
(added: I can see that the rectangle isn’t square, no 90 degrees)

@wilschroter , Typing 2’,2’ for me results in 2’x 2’, irrespective of precision settings which in fact does not affects how precise SketchUp works. It only affects displaying measurements.

(**) edit; Due to exploding the imported model the shown axes reverted to the systems axes.
The imported model as a component itself revealed its slightly rotated axes as far as the rectangle. Good catch @Box )

Wow that’s a great catch. What can I do to get the benefit of shifting my axis while assuring it has an accurate reading? Right now I have been grabbing an axis from the original cad model but I can now see how that could cause problems.

Whats a good display precision if I’m never going more than 1/32nd of an inch? I’m assuming 1/32 but just want to be sure.

You may already use a good display precision. You could see the value wasn’t exactly 2 feet, but you didn’t need SketchUp to say 2.0004516 or something to know that.

My preference is to set Display Precision as high as I can for the units I’m using. In Architectural units that would be 1/64". That doesn’t mean I have to create things to 64ths and it doesn’t make the model anymore precise. What it does is allow me to see those tiny dimensions if they occur and deal with them before they become onerous to fix. If you are going to later add dimensions in the SketchUp model you can change the make the display precision more coarse. And this setting has nothing to do with dimension precision in LayOut.

But with Display Precision set to 0" it’s not easy to tell if the dimension is 2.0046 or 1.944 so it’s harder to fix.

And of course in reality those discrepancies would matter. The actual build is likely going to be off by much more than that anyhow. But a little error here and a little error there can add up to a big error down the line that might need to be fixed. Easier to keep thigs right from the beginning instead of having to go back through and find the problem child and correct it.

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And in the case of this specific model it is actually snapping out of square, so it would lead to a nightmare down the track.

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If I type in a 2x2 measurement for a square, how can it not be “square”?

But if I only typed in 2x2, how did I get this bizarre long value?

Here’s the result of the out-of-square @box pointed out. I doubt you can get all sides equal with this strange distortion!

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Who knows? With little mistakes like this it’s often harder to tell where things went wrong in your work flow than explaining how to avoid them in the future. We all went through these mistakes.
And believe it or not, I’ve spent many houres finding out about limitations of SketchUp while modeling. Creating a rectangle 2’ x 2’ isn’t one of them. Somehow (but how?) the user must have done something odd. Don’t take it personally!

I’m on my phone now so can’t look at the model, but there is something very odd with it. Perhaps a .dxf import, even the coordinates of points have tildes.