Fan Panel, 1U — 40 mm, 7.5-inch

A 1U fan panel for our 7.5-inch rack, for one to three 40 mm fans.

Three, not five. A 40 mm bore plus the walls either side of it needs 44 mm of panel, and the field between the mounting slots on a 190.5 mm panel is 160.6 — so three fit and four do not. Three 40 mm fans in one unit is still more air than most of these racks ever need.

Round bores, not square holes. A 40 mm square opening in a 44.45 mm panel leaves a 2.2 mm rib top and bottom; a circular bore leaves 3.2 mm at its thinnest and the full panel at the edges. The printed guard over each bore is concentric bands cut by radial webs, and the webs are the same width at the hub as at the rim rather than wedge-shaped.

Choose: how many fans, and the guard — rings and spokes, or none at all.

In the box: the panel and four M4 x 30 self-tapping screws per fan. The fans are yours: every make is different and anybody cooling a rack has opinions about noise.