# Advanced Cross the Beams 3d Puzzle (w/ free SVG)

This is a step up from the original cross the beams puzzle, with twice as many crossbeams. You might think to yourself “Ah, twice as many beams, twice as hard, right?” Not so much. this is surprisingly tough.

Here’s the SVG if you want to try it. Be sure to zoom out to see out-of-frame details about how to scale this model for other materials:

See this thread for more details on how to use the thickness gauge in this SVG :

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you’re on quite the puzzle streak right now.

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We will be long entertained with your puzzle streak! Thank you!

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The variations of combinations would be exponential, not just double; so this one should be much more difficult.

But, I will have try after I get back from a two week missions trip. We are leaving this weekend and I still have so much to do before we go.

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Yeah but I’m not sure exactly which math to apply here. It might be a factorial progression, not exponential?

There are also multiple variables because now you’re also introducing chirality— how you assemble the cross pieces and box can be done “incorrectly”, which makes for even more options. There are ways to assemble the box that make the solution impossible, and there may be ways that make it a complete mirror image of how I designed it. I haven’t tried to figure that out either, but in principle it seems correct.

In the end I have no idea how to quantify just how much more difficult v2 is compared to v1, except to say that it’s significantly so.

I have visions of a larger more complex v3 but just making this one hurt my brain so I don’t know if I will do it unless I come up with something interesting— a new solution type of some other kind of novelty. We’ll see.

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I found this true with the first one also. I assembled one cross axle in a way that it wouldn’t fit with the others once, after having completed the puzzle several times.

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To make the math even trickier: Only 4 of the 6 crosspieces in the new model can be assembled incorrectly. I guess that means there are 2 ironclad and 8 possible piece pairs and you only need 6 total? I don’t even know how to approach that math.

Anyway, I didn’t want to make the puzzle completely impossible so the SVG essentially has the solution baked right in if you choose to use it.

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Thanks, need to fire up the Glowforge! My lid is coming loose, and over been dragging my feet on fixing it

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