The fabrication of the light trap is in progress. Here you can see the fibreglass cloth in the female mold, with the fins held in place by strips of balsa while the resin sets.
The light trap will be placed directly opposite the focuser. Its purpose is to prevent any light that may fall on the tube wall that is not blocked by the secondary mirror/holder will not find its way to the focal plane. This is achieved by effectively recessing the wall of the tube and angling the fins such that any light that does manage to strike the light trap cannot be reflected into the focuser.