Tolerances are + 0.1 mm
Material... Most softwoods are suitable, but the type 2A and type 2B
were always made in hardwood for extra strength and resistance to
Standard Top bars... upper is the alternative type, lower is
the original 'standard' type.
Apex type 2B Top bar
In order to limit the places where wax moth could pupate,
the central groove did not run to the ends, but finished at a point
that was covered by the sidebar.
Apex type 2A Top bar
This 2A type was manufactured in two forms... The one shown
here was used for cut comb production. The other type (future link)
was without a groove, had drilled holes and was used to mount pairs of
half width breeding frames for use in full sized brood boxes.
Top bar for drone frames
Written... Summer 2000,
Revised... 03 October 2001,
Revised... 20 August 2002,
Revised... 07 June 2003,