The indentations for nuts in the middle layer for Ergodox tenting kit are too large

[vjraitila]

Guidance for using the Ergodox tenting kit on an Iris instructs choosing a set of M3 nuts for attaching the legs. The standard width for DIN 934 M3 nuts (across the flats) is 5.5mm. However, the indents for the nuts have a width of 6mm in the design for "Iris R4 Middle Layer - Ergodox Tent Kit for 1.5mm Plate".

As it is already difficult to get the legs fastened tight enough that they do not become loose, this makes it next to impossible as the nuts are allowed to spin freely in their slot. Or have I missed something obvious here?

I tried fixing it myself, but lack the skill to do this neatly with just the mesh file being available. I thought about even switching to a 5.5mm square nut instead in order to make it less likely to spin.