A thinner grafting frame simply works better.
I’ve used a standard 1 3/8″ frame for a grafting frame. The cell bars were wide and would carry two staggered rows of cells. They added a section of comb above the cell bars. A bottom bar reinforced the frame ends.
This year, I’ve done a little experimenting with a thin grafting frame and bar. The frame is home made and is about 3/4″ wide which is slightly wider than a queen cell with a bee space on each side. It’s a simple frame.
I like the results I get when using this frame.
- bee density is easier to maintain
- the bees have an easier time controlling the environment
- cells toward the ends of this bar are as high a quality as cells toward the middle
It appears, the bees find and tend the cells faster. So far, the acceptance rate on my grafting with these bars is 99%-100%. I normally run about 90%.
This thin frame consists of a top bar 3/4″ x 5/8″ x 19″. The End Bars are made from the same stock as the top bar. They have a dado cut out of each side to hold the cell bars. These frames don’t have a bottom bar.
The cell bars are made from the same stock as the top bar and sides. They have a single saw kerf down the middle to accommodate my JZBZ plastic cups. A little beeswax in the dado cuts adds enough “stick” to keep the bars from sliding out when the frames are handled.
Two frames are used in place of one standard sized grafting frame. This spreads out the cells providing a closer match to natural queen cell densities.
As a side note, I coat my plastic cups with a thin beeswax coating. And I do the same with all new grafting frames and bars prior to their first use.