Kossel column enforcement

I've created those column reinforcement squads for reduce vibration on top.

For 15x15 openbeam

BOM: 9x M3 Screw 0.8mm length
9x M3 Nut
9x Grover washer (1mm max)

The nut on the column is reworked like a T-nut (thin side, but it works) for column open beam).

MOUNTING: Insert the Internal screw (with grover washer) in the hole +nut other side;
Place the external nut in right position in the open beam;
Turn the squad perpendicular to rail (column side out), insert the internal nut in the rail first, then adjust position to fit the external nut. Insert its relative screw (remember the washer);
Insert the column screw + reworked nut in squad and insert it in open beam;
Repeat this operation for all six squads, then tighten (not to death, t-nut aboveall)

Fututre improvement: Connect the two column's squads for reduce printer axial torque.