I am a strong advocate for Langstroth and especially 10 frame Langstroth hives. One of the primary issues I have with the eight frame standard adopted in Australia is the frame spacing and internal volume. Consider the following measurements which have been converted to metric for an Australian audience:
A 10 frame hive containing 10 Hoffman 35mm frames has a total frame width of 350mm. The internal size of a wooden 10 frame hive in Australia is 362mm. Using this sizing, the additional 12mm can be attributed to the spacing provided from the firmly centred frames to the internal sides of the hive wall, 6mm on each side.
An 8 frame hive containing 8 Hoffman 35mm frames has a total frame width of 280mm. The internal width of an 8 frame hive in Australia is ~310mm. This wider dimension provides a total of 30mm additional spacing from the firmly centred frames to the internal sides of the hive wall, 15mm each side. If this measurement is derived from the total frame width, it should surely be less, not more.
Speaking to several manufacturers of wood ware in Australia, there was some level of acceptance that something is ‘off’ with the spacing of 8 frame hive boxes, and it has been this way for some time.
The following article extracted from ‘Gleanings in Bee Culture’ from 1891 suggests ‘some time’ may be closer to 125 years. The attached article possibly provides some insight into the path that resulted in this persistent anomaly with 8 frame hives.
The article discusses the improvements and changes to the ‘dovetailed’ hive design which was a popular benchmark for improvements and developments with the Langstroth hive.
The specific points of interest are the following:
The hive and supers are 1/2 inch wider: instead of being 11 5/8 inches wide inside, they are 12 1/8. This makes room for the addition of a dummy or division-board in the brood-chamber, which is to be first removed before handling the frames. This additional 1/2 inch gives room in the supers for a follower and wedge making it possible to have side pressure on the section, which is so desirable.
In the late 1880s and early 1890s division/follower boards appear to still be an integral part of Langstroth hive management. The division board is designed to actively manage the brood space by having a movable wall (the division/follower) on one side of the hive that is pressed up firmly against the end frame to reduce the brood space. This adds the flexibility of variable brood sizing eg. from 5 to 8 frames without increasing the brood cavity volume with empty frames. This division board can also be used to split the brood chamber if the beekeeper wanted to host two colonies in the same hive box eg. two smaller nucleus hives.
The measurements that are discussed in the article convert to the following metric measurements:
11 5/8 = 295.3mm
12 1/8 = 307.9mm
This suggests that the 8 frame super was originally closer to 295mm, and the addition of a 1/2 inch division/follower board and increased spacing pushed the internal width out to 308mm.
Although the 308mm internal width isn’t the current standard (although very close), it should be noted that the current measurement of 310mm is closer to the ‘wide’ measurement of 308mm (+2mm) than the ‘original’ measurement of 295mm (+13mm).
Frame width of 280mm for 8 frames with a 295mm internal hive width provides 7.5mm spacing from the side of the centred frames to each side of the hive. With rounding considered, this falls eerily close to a valid bee space measurement (http://www.dave-cushman.net/bee/bsp.html).
So why wasn’t the 10 frame hive modified in the same way and widened for a follower board? great question.
2020-02-09 - Fix transcription of 12 1/2 to 12 1/8 after feedback in thread from @FreeBee. Remaining references updated to reflect change but no change to conclusion
2017-03-07 - Re-phrase again for 10 frame sizing and use 362mm measurement as base for calculations
2017-03-06 - Include feedback from Laurie on 10 frame hive sizings in Australia