I ripped up a 2x4 into 1 1/2 squares, then ripped it again at a 30 degree angle to make an equilateral triangle. cut them into 18 inch lengths. Then cut a flat edge with the band saw so it will rest flat on the top bar hive, and also it will fit on the lang hive the short way. Hope you can follow this, I will take some pictures. Then I melted some wax and brushed it on the down edge.
I have one TBH with cross comb that will not go straight. It was one that I delayed removeing the queen cage and the combed in the cage. The comb on either end is perfect but the middle is a mess. So I replaced 4 bars of cross combed bars with this new top bar.
The "design" is based on an old Kelly style foundationless frame that my supplier has at his shop. Jst a triangle shape.
Advantage will hopefully be twofold. First it is so big and straight that it hopefully will be hard for them to cross comb.
Second, that it will permit interchanging brood into a lang style (although the frames will necessarily be criss crossed from the standard frames).
Third it is a lot quicker and easier to build.
Interested in comments.
I had some capped brood along with the capped honey that was necessarily removed. So I just removed a frame from a honey super of my lang hives and threw it in. Hope it works. Anybody ever try that? There was honey on the edges of the brood comb and they were all over it. My Langs were also started from 3 pound packages, but were started a month after my TBH's and are not nearly as strong.
Best part was the harvest payoff. WOW what great stuff! got about a pound of honey. My first harvest! Even the wife said, wow that is good stuff.