Where do you get 8mm strips of wood?

[user 20297]

A 1/4" (6mm) strip of wood is fine. The reason is that the top of a frame should be slightly below the top of a hive to allow for plastic or metal spacers, which is what used to be used rather than hoffman self-spacing frames. The 'slightly lower' bit gives you the extra mm or two you need to get the ideal bee space.

Look at the National hive dimensions. Frame top bar thickness is 3/8" (9 mm). rail depth below top of hive 7/16" (11mm). You've got the 2mm you need with a 6mm rim around the crown board, it was already in the original design oodles and oodles of years ago.
Simples

I think I can see the logic behind that when using thin timber for hives; it might give an allowance for shrinkage and swelling. But polyhives (Abelo at least) are precision made and won't change in dimensions. As far as I can tell, they are almost perfectly 8mm below the bottom bar of a frame to the rim and a fraction of a millimetre from the top-bar to the rim. The imperfection is more likely in the frames themselves.

When I assembled my wooden boxes, I found it easier to construct them with the rails set to match my frames rather at a prescribed measurement involving sixteenths of an inch! Therefore all my frames are as flush with the top edge of their boxes as I can make it.

What works on one hive obviously doesn't necessarily work on another.

 

[blackcloud]

The final word has to be from the bees as ultimately they will decide the correct space - "whatever"

 

[Pembroke]

You can get ply wood in 4, 5 or 6 mm thickness, cut a 1 to 1.5 cm wide strip of that and stick either side of the crown board around the edges. A timber merchant can do you a sheet which should last for ages or the chain stores (Wickes, B&Q Etc) will sell you half sheets that are a bit more expensive. A table saw will make it easy but it can be done with a straight rip saw.

 

[pargyle]

You can get ply wood in 4, 5 or 6 mm thickness, cut a 1 to 1.5 cm wide strip of that and stick either side of the crown board around the edges. A timber merchant can do you a sheet which should last for ages or the chain stores (Wickes, B&Q Etc) will sell you half sheets that are a bit more expensive. A table saw will make it easy but it can be done with a straight rip saw.

If you use plywood I'd give the strips a good coat of varnish before fastening them to the crown board - plywood will aborb water and will delaminate given half a chance - pay particular attention to the cut edges ....

 

[jenkinsbrynmair]

If you use plywood I'd give the strips a good coat of varnish before fastening them to the crown board - plywood will aborb water and will delaminate given half a chance - pay particular attention to the cute edges ....

even after sealing the cut edges it will soon delaminate

 

[Rockape83]

I cut mine from the 9mm x ? cladding that seems to abound many abodes now, just run through the table saw or originally hand saw and cut to length.

 

[sean-a]

If I weren't able to make my own, I think I'd be tempted to find a local woodworker and negotiate to get exactly what I was after, perhaps with a few jars of honey. Or there might even be someone in the local BKA who can do it, but they'd possibly not have their head turned by an offer of honey

James

Having just bought two 2.4m lengths of crappy pine for £11 from Homebase, the rims for each floor have cost me almost as much as the wood for the underfloor entrances!!!
Should have asked the guy to cut an 8mm strip off the wood before he cut it for the floors!
Note for next time!