This page is credited in full to Dave Cushman who created it. His voice is expressed in black colour text and any additions or comments in blue belong to myself. Credit: Dave Cushman’s website.
PH.
Pollen Stripping Screens
Round Hole Pollen Stripping Screen welded 5 mesh pollen stripper Various types of wire mesh have been used to cause some of the pellets of pollen to become detached. The type illustrated immediate right has every junction resistance welded at a pitch of 5 mm, so that the mesh is rigid and each hole has it’s dimensions controlled as no movement of individual strands is possible.
Woven Wire screens can be used, but they have the disadvantage that narrow strips, such as in required for vertical stripping screens. These are easily corrupted in handling with some gaps becoming too narrow and others becoming wider than required, reducing the effectiveness.
Round holes in plastic sheet are also popular as is shown in the right hand picture. Two colours are shown that are common in Europe (I guess Polish or Czech manufacture), but I have also seen grey and white, as well as aluminium versions.
Star Shaped Pollen Stripping Screen My personal favourite (and probably the most effective) is a plastic sheet one millimetre thick that has a number of star shaped holes punched in it. Simply due to the action of a bee climbing through these holes means that many pellets are removed.
The type that I use is 55 mm wide and 342 mm long, I drill some 3 mm diameter fixing holes along each edge and then use “System Zero” Screws to attach to 6 mm (or 9 mm) plywood panels that have been cut out to take them. See “Rational” Pollen Stripping Screen.
The star shaped stripping screen started life as a hole with four small slots around the bottom part of the circumference. (bees legs are underneath and the original usage was vertical).
The snag with this arrangement is that the punch and die suffered side thrust during the punching action, due to uneven resistance and instead of designing a ‘shear proof’ punch and die it was decided to make the slots radiate in all directions and thus even out the stress. Hence the star shape… Because a star is even in all directions horizontal placement of the screens became sensible.
The photograph itself was too poor to reproduce and so I have drawn a facsimile of it to show how it was used. The mesh that the pellets fall through should be 6 or 7 mesh, although I have had success with 8 mesh. (Which was used, simply because it was available.)
Star Shaped Pollen Stripper, original hole shape, mounted on a trap
Arguably the only way of gaining safe pollen for spring stimulation is to garner it yourself, or rather collect it from your bees. A week is long enough though for a colony to be worked for pollen lest they suffer a dearth.
PH