> From:    Murray McGregor <[log in to unmask]>
>
> Moisture certainly can get into the material. I wondered why our
> polystyrene feeders were turning black on the outside and clumps of bees
> and wasps were hanging about on them....
> .... as the syrup migrates into, and right through the polystyrene
> between the beads.

This need not happen. I haven't painted any of my hive parts inside.
It's true I got a few feeders that behave like you say, but they have
less density that the others. This mostly happens when I have given a
one box split too much feed in autumn and they can't find room for it
all so it's left in feeder over winter. Apparently the manufacturing
process is quite difficult to control when it comes to density. Almost
every batch that's made is a little different and density varies 10-20%
between batches and can also vary in the same batch. Producers say
+-10%, they can't get closer. 80 grams is in my opinion too soft, so you
would have to aim at near 100 g/l to make sure it never gets below 90.
Feeders are more difficult to make and often have less density at the
top. You need min 90 g/liter. I know some producers try to cut cost by
making them softer.
>
> Roofs taken from store in spring are surprisingly noticeably lighter
> than those on the hives, but as summer comes on they are about the same.

I haven't experienced it with a roof, but with bottoms if they are soft.
Water stays at the bottom all winter and when freezing it expand and
break up the material. The small cracks are getting wider and more water
leaks in and freeze-expand until the whole bottom board is like a
sponge. Doesn't really matter, but when going to estimate feed amount in
spring by lifting hives you make errors and don't realize the hive might
be low on feed. Don't know what hive you have, but there seem to be some
difference between makes. Bottoms from Finland that Juhani Vaara makes
have sloping surfaces that makes water run off and probably will last
longer in a climate like mine. Time will show.

--
Regards

P-O Gustafsson, Sweden
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