How do RCNC,

Below is a pic of how they will be mounted, the bed will be 60mmx25mmx3mm wall,mild steel box section.

The flange will fit through a 25mm hole in the 60mm wide part of the box section and the shoulder will either be held in place by 4x nut&bolts or self tapping screws? the little red boxes are 2x grub screws and the rail counter sunk to accept those grubs.

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