Infinity Loop Tube Design

[engineeringYR7JU]

I am trying to make an infinity loop out of 1.25" tube for a dance studio. These are basically two identical rolled tubes that are attached together. The problem I am having is where the loop crosses itself in the middle. I am trying to form the tube where it is offset at the point of intersection. I hope this makes sense. I have attached the sketch of half the loop. Its overall width and height are critical.

Thanks for any help you can give.

Inventor Pro 2025

Casey

[kacper.suchomski]

Hi

You should also include a hand-drawn sketch of the desired outcome.

[engineeringYR7JU]

Hope the sketch helps.

[kacper.suchomski]

Just draw a side sketch that shows the bending of the material, then use the curve intersection tool in the 3D sketch. This will give you a path that will look like an 8 from above and a slight trough from the side.

[engineeringYR7JU]

Is there a video somewhere on how to do this?

[kacper.suchomski]

[Pineapple2024 · Accepted solution]

IV2023

[engineeringYR7JU]

Pineapple2024,

Thank you very much for taking the time to do this. I have never had to do anything like this. Even though it looks fairly simple. I am used to flat parts only. I will look at this more after the weekend. Again, I thank you very much. 

[engineeringYR7JU]

Pineapple2024,

The only issue I am having is with the constraints and getting all of the parts to align and miss each other.

[Pineapple2024 · Accepted solution]

Model it flat.  Whoever welding it should be able to "twist it" to fit.

Make the 2 loop and fit straight to them.

[SBix26 · Accepted solution]

Here is what @kacper.suchomski was suggesting, a 3D sketch curve created by the intersection of two 2D curves.  After creating half of the loop, I simply patterned it 180° to a new solid body, ready for welding at each end as you showed in your sketch.

The attached file is Inventor 2025 format.

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Sam B

Inventor Pro 2025.1.2 | Windows 11 Home 23H2

[engineeringYR7JU]

That is exactly what is supposed to look like. I appreciate you taking the time and effort to do this. I will take what you have shown and explained and use it for future projects.