Naim Olive Knob Base Piece

Naim olive era (mid to late 90's) preamps and power supplies have three-piece knobs for volume and input selection (e.g. NAC62, NAC72, NAIT2) and power (HiCap). There is a cap (plastic), a grip (rubber), and a base (plastic). The base piece contains a grub screw and square washer that secures it to a 6mm diameter shaft.

If the grub screw is overtightened (e.g. to eliminate play), the back part will crack and the knob will no longer be able to be attached.

This is a stronger version of the original base part, with more reinforcement behind the square washer. It also features a cradle to help align the grub screw with the washer when assembling. The photo shows the OEM part on the left (not broken in this case) and the 3D printed part on the right.