Gary, is that the Xara QuickShape Hexagons?
If it is my construction then I have tried with this: SVG - Cubes.xar
I did get some very faint lines appearing at some Zoom values across the cut Blue face so I simply added a blue background.
These will be browser and graphic card artefacts that usually only appear at scale so use a small background-size also sorts this.
Acorn
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