Portcullis or Round Bee Escape Board

The escape is made from translucent plastic and is 99 mm in diameter with the exit slot having 7.5 mm clearance so that drones may have an easy passage.

The device has multiple plastic fingers (the yellow items in the drawing). Each finger is light enough for a bee to lift by running underneath it, but it is heavy enough for gravity to hold it in place.

I found in practice that as supplied there was so much play between the bearing holes within the fingers and the pin that forms the bearing that the fingers could be pushed sideways and a gap opened up that was large enough to re-admit a worker bee. My cure for this was to fit small brass washers between the fingers so that the play was taken up.

If I ever make any more pollen stripping boards I will use this type of escape to allow the drones out... I currently use porter escapes for this purpose, but sometimes drones are a tight fit in these and get stuck.

Owing to the fingers being held closed by gravity... This form of escape can only be used in a horizontal plane.

When used to clear bees from honey supers it is possible to entirely empty the supers, but this takes 48 hours or maybe more to achieve.

To mount this unit through a 9 mm board you will need to cut a 70 mm diameter hole.

I use two escapes per board, one on the centreline and one halfway between the centre and the edge.