Chopper disks are well known for their use in optical physics but also are fixture of neutron research. Choppers are a mechanical method of repetitively switching light or in our case neutron beams on and off - thereby turning said beam into signal. They consist of a slotted rotating disc through which the beam passes producing the chopping action. Said action can be adjusted to the researchers needs by varying the rotational speed of the disk.

Unfortunately choppers used for experiment with light sources are not directly transferable to neutron research - a simple metal or plastic disk will not be sufficient to block off the neutron beam. A material that has a much higher density like boron is needed as an absorber.

The problem with boron-carbide or boron-nitrate is that there are just a select few materials which can be homogenously combined with it and even those few that can (aluminium, rubber) are very restricted in the geometries they allow for. Additionally due to the high hardness of the boron any post-processing such as drilling and milling can become from prohibitely expensive all the way to nigh impossible. 3D-Printing is therefore the logical next evolution of use-case specific neutron application.

This led to development of PANApps first chopper disk which combines an aluminium disk with machined grooves and mounting holes with 3D-printed boronated plastic inserts as an absorber. The top piece with the aperture slot is interchangeable with a multitude of differently sized inserts to allow maximum flexibility during daily use. The chopper was successfully tested December 2022.

An improved design is already in the works and is expected to release mid-2023.