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# Adjacent cubes (pixels), do they print well?

Adjacent cubes (pixels), do they print well? [message #47131] Tue, 17 April 2012 23:39 UTC
Hey guys, quick question... If I print a series of cubes, all touching each other at the edges/faces, but not actually as a single combined object, would that cause any trouble in the printing?

For example, if I want to make a pixel-art of cubes, with cubes like this:

[ ][ ][ ][ ][ ]

The cubes are individual objects, they are touching but not intersecting. I don't want separate cubes printed, I want one continuous object.

Does anyone know if that'll cause a problem or does the printer see it as one single continuous shape?
Re: Adjacent cubes (pixels), do they print well? [message #47133 is a reply to message #47131 ] Wed, 18 April 2012 00:35 UTC
Anything you want stuck together should really get hit with a boolean union and be a single mesh.

Sometimes union fails, faces that are just touching can be especially problematic. But often, if you just flip the cube onto a different side, it will work again because the triangles will be different.

[Updated on: Wed, 18 April 2012 01:29 UTC]

Re: Adjacent cubes (pixels), do they print well? [message #47135 is a reply to message #47133 ] Wed, 18 April 2012 01:18 UTC
If you have two faces that both have exactly the same coordinates, you are going to get a "Manifold Error"

It's better to have either a microscopic gap or a microscopic overlap. Just don't make them congruent.

Patience, Persistance, Politeness - the 3Ps will help us get us to Perfect Printed Products
Re: Adjacent cubes (pixels), do they print well? [message #47196 is a reply to message #47135 ] Wed, 18 April 2012 23:28 UTC
Understood. I'll make my "pixels" overlap just a tiny bit then. I can just select them all at the end and scale them all up at once, hopefully that'll work.

Thanks guys!
Re: Adjacent cubes (pixels), do they print well? [message #47207 is a reply to message #47196 ] Thu, 19 April 2012 05:08 UTC
You might still run into trouble I think. With two cubes next to each other, then scaled up a bit, there are still faces of each that lie in the same plane. I think it can get confused when taking the union. You might be ok though.

The best way would be to start with a set of points that will be at the centers of the cubes, then build a mesh that figures out the right shape of the union of the cubes. This shouldn't be too hard if you can write a script somehow.

All the script has to do is for each point, look in the 6 directions away from it. If there is a neighbouring point next to it in this direction, do nothing, otherwise put a square into the mesh between the point and where the neighbour point would be.

Then all of the squares taken together make the correct mesh.

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