my first hives were marine ply and 25 years later still in use,
This says it all. If you put the effort in (if you have the inclination) plus the time, tools, patience, budget etc to make an
excellent job, the result will last longer. This is a basic concept that applies beyond bee-keeping. To clear up a point, shuttering ply
is WBP - just an inferior grade. Ply is graded a,b,c etc on each face, the reason being that some applications need two good faces but in most scenarios, one face can be a lower quality (ie wall covering?) There is also the situation that lower quality ply has gaps in the layers that only become evident when you rip it and expose those flaws? I've had sheets from a wood merchant (as opposed to a DIY store) that I have ripped to a plan (obviously to avoid waste) and whilst they look great on the faces they have been crap on the cut surfaces with numerous long deep voids. These voids can seriously affect the integrity of the structure, such that when moved sideways on the hive ( as you do) the face surface (which might only be one layer) can split away.
The obvious answer is to take the bits back to the retailer and demand a refund. The route I have followed in the past has been to line all the exposed edges with a (10mm) sealing edge. A lot of fiddly inconvenience but I should reap the reward in a longer life (the boxes not me
)
Which is the point I made when I started
I thenk yew
BTW
the best ply I have ever seen was some beech lined, mahogany ply, school benches ( rescued from a skip, yes) They spent 10 years on an allotment in the open and have just been made into sparrow bird-boxes. Ripped up a dozen of them and not a single flaw in the construction of the ply.
Caveat Emptor
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