Originally Posted by Foxbat
The link, unfortunately, is not working for me.
I've seen a modern recreation of the boar sword sketched above by an experimental historian. Apparently the cross piece was made to be removable, possibly screwing together, rectangular on the main piece to fit the slot and prevent rotation, but drilled & tapped for a mating screw on the opposing arm. Each had a shoulder behind the bit that went through the slot to hold it from both sides. Unfortunately there was no pic of it unattached to the blade.
Screen dump: for those of us without the whole book
and a picture of the crossbar on the original museum piece at