[Kevinf]

I want to build a robber screen for my two top bar hives which have entrances on the front, but to the side. As a result of being on the side, I have a 60 degree angle to contend with which does not allow me to build a traditional Langstroth robber screen as I quickly hit the sidewall with the screen. I certainly cannot go the 4" that I oftentimes see recommended as the minimum height.

If I build a screen that is enclosed on the top and bottom, but has gaps on the side will robber bees be able to more easily access the hive? How small should the gaps on the side be?

When I eyeball it, it seems like the gaps are fairly large and might prove ineffective.

Thanks for any thoughts.

Kevin

 

[little_john]

If I understand your entrance configuration correctly, it may be worth considering having enclosed sides and top to the screen, and leaving the bottom open for access ... ?


Fwiw - here's an example of a tricky anti-robbing screen install ...

Some years ago I built a WBC-looklike cover to fit over a standard British National Hive:

Dunno about it's looks, but the uPVC certainly keeps weather off the boxes, and should last for 100 years. However, I couldn't see any obvious way of providing a simple, detachable anti-robbing screen - so, as a temporary measure a piece of fine aluminium mesh was glued to the underside of the bottom lift, which then hung down until it touched the landing board, thusly:

The hive access slot was centralised and reduced to around 1.5", so that there was then somewhere around 4" to the access points at either end of the mesh. It has worked so well that I haven't bothered to change it in any way.

There's probably about one square inch of access at either end, but I don't think that's important - unlike the horizontal distance between the actual hive entrance itself and the edges of the mesh.

'best
LJ

 

[Kevinf]

Thanks, little_john.

To be clear, your escapes in these photos are to the side, correct? They are just located 4 inches away from the hive entrance?

Does it matter where the escape is? Could I have an escape to the bottom if necessary?

Kevin

 

[little_john]

Thanks, little_john.

To be clear, your escapes in these photos are to the side, correct? They are just located 4 inches away from the hive entrance?

Hi Kevin - Yes, and yes. I've just been outside to measure the screen (as that cover is not being used at the moment) - the side entrances are actually 4.5" away ...

Does it matter where the escape is? Could I have an escape to the bottom if necessary?

I've never tried bottom access, but I don't see why that wouldn't work ok - there's a hive called "The Sun Hive" which has the main hive entrance directly underneath it - i.e. from below - (the hive itself hangs in the air), which the bees are happy enough using.
LJ

 

[little_john]

Kevin - just curious (I might have an idea or two) - what shape are your entrances - slots or round holes ? A sample photo would also be handy, if you have one.
'best
LJ

 

[Kevinf]

Hi little_john,

Here are a couple of photos but after thinking about this a little more I don't think my solution is all that difficult. All I need to do is cut the bottom of two strips at a 60 degree angle as that is the angle of my exterior side wall. The angled bottoms of those strips will be on the landing board with the rest of the strip extending vertically up the wall. I then cut two horizontal pieces of sufficient length which I will attach to the two vertical strips with the mesh screen in between. I will need to screw the completed robber screen into the hive since it can't stand on its own due to the angle vertical strips.

What do you think?

Kevin

 

[little_john]

Hi Kevin - I'm attaching a graphic showing what I think you're describing (might have misunderstood you, of course) ...

(Wood coloured light brown, mesh coloured grey.)

If I've got that right, then it would be better (imo) to have the entrances to either side of the screen, as a top entrance would appear to be offering something of an 'invitation' to all approaching bees. If you really want to stick with a top entrance, then making the sides triangular so that the mesh then presents a vertical face to oncoming traffic would be one way of dealing with this.

Attachment ? - screws are one way, hook and eye another. I use magnets and broad-headed tacks to provide a clip-on, clip-off solution - handy for cleaning-out dead bees dumped behind the mesh. http://heretics-guide.atwebpages.com/beek06.htm

Thanks for the photos - I didn't realise you had made a projecting bottom board, and there's a chance that this horizontal surface might cause pooling of water if you ever get rain with some serious wind behind it, although of course the KTBH overhang should prevent this from happening during lighter conditions. Just thought I'd mention this as being something to keep an eye on. We have the same issue with the end boards of our 'National' boxes, the bottom batten of which is bevelled (coloured light brown in the above graphic) to allow rain to run-off rather than pool.
Sometimes I make boxes with this bevel and sometimes I don't - it doesn't appear to make a whole lot of difference in practice. But then I paint my boxes and always attach the lower batten with waterproof glue, and even apply an additional sealing bead of glue along the top of the bottom batten to prevent water ingress there.
'best
LJ