This project started out as an idea for producing small quantities of this rare commodity by utilising an existing queen excluder manufacturing jig belonging to B. J. Engineering.

As demand was greater than originally anticipated it became sensible to make a jig just for the exact requirement of drone exclusion (retention). I produced a drawing of a panel of gridded wires that could be manufactured to suit frames sized for B. S. National (& Smith) Deep, B. S. Commercial 16" x 10" and Langstroth Deep.

The limited size drawing below gives an overview of the design, if you would like to see a more detailed version that has a greater definition... Click on the picture and you will be taken to a drawing that is represented at a little over life size, but you will need to scroll across the extra wide page.

During jig manufacture for this project, several snags arose, that caused changes to be made and it was decided to make two jigs one for National and one for a composite grid that could be cut in two different ways to give both Commercial and Langstroth versions.

The shallow versions of any of these types of frame can either be manufactured at shallow size (if a large quantity is required) or cut down from full grids.

The grids have 2 mm wire on a 7.2 mm pitch giving a window space of 5.2 mm. The wire material is hard drawn steel and has a copper coating (the same as is commonly used in making lamp shades). Fabrication is by resistance welding.

The grid at right is a half width panel of a National sized specimen and is rendered at 50 pixels per inch resolution. Such a panel can be used either on half width National frames or on the drone frame that has been devised with four 'compartments'.