Problem with instanced mesh precision?

I’m making blocks out of instanced square faces so that I can modify the sides of the blocks individually. The square mesh has exactly 32 length on each side. I create the instances in exactly the right transforms to make a cube:

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There is a small barely noticeable seam though. I’m not really sure the best way to get rid of that, but I’m dealing with it for now.

The problem comes when I scale up the instanced mesh. It creates huge gaps at the corners and edges:

One possibility is that my square mesh is not importing so that the vertices are in precisely the right locations. How to I check the individual precise locations of the vertices of my mesh asset in Unreal?
The other possibility is that the instance transforms become inaccurate when you scale up an instanced static mesh. I’m trying to find out if this is the case and what can be done about it.
Or could it be some other issue that I’m completely unaware of?

Okay, so far I’ve found some threads where the instances get shrunk when they’re rotated. Haven’t found any solutions but it might be my problem.
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Does your mesh have 8 vertices? You can always use starter content from unreal for something like a cube.

no. It looks like I’ll have to figure out which rotations decrease the mesh scale by which amount in which axis and then when I create an instance, raise the scale I give it by just the right amount so that it gets shrunk back down to the scale I’m looking for. bleh.