I started building my own equipment in 1977 including building deep Langstroth frames with 31mm end bars. At that time, I was using Langstroth 10 frame equipment. Since I was doing deeps, I decided to make shallow frames also with 31mm spacing. I could just fit 12 frames into a shallow super so off I went to the hives and put a few on with 12 frames. The bees would draw the frames from foundation with no issues, but when it came time to extract, I had a problem. Most of the combs had one thick side and one thin side which caused a lot of grief extracting. The thin side of the frame was lower than the wooden parts so a knife would not uncap the cells. I figured out that 31mm frames are a waste of time in extracting supers. Since I have square Dadant equipment, I now put 13 frames in a super to get them drawn and then cut back to 11 or 12 frames for honey storage. Thick combs make extracting much simpler.
When I started building frames for the Dadant deeps, I made the end bars to allow for 32 mm spacing. This factors in a bit of propolis between them with 14 frames in a box. This configuration combined with 5.1 mm cells results in faster spring buildup by about 2 or 3 weeks. I can usually split my hives by mid March with the main flow starting about the 20th of April.
