Here's one I made out of bocote this weekend. Changed a few things up with this call. Some of it I like, some of it I don't.
The toneboard part of the insert was turned out of some 5/8" Delrin rod that I recently got. Lots cheaper than acrylic and to me it sounds the same. I drilled it into the bocote square before turning the insert and secured it with CA glue. That actually worked out really slick.
I hate the proportion of the insert in comparison to the barrel. It is 1/4" to long in my opinion, and a bit too fat.
Something happened to me on this one that hasn't happened to me before, although I have read about it happening. I turned the barrel, turned the shoulder for the aluminum Gouldman band to go over. Finished the call, then went to put the band on it the next day. Loose!!! Too loose to salvage unfortunately. The wood shrunk up overnight. I once swore that wouldn't happen with dried woods, so I'm eating crow on that one.
Sooooo, I had no option but to make an acrylic band for it. That was a challenge, and I hadn't tried it before. Had to create a wood tenon that went into a mortise in the acrylic band. Polished it and CA glued it on. Worked out slick, but the band is a bit narrow for my taste. Didn't have a choice on that.
Aside from the band diameter and the insert length I'm happy with it. At least it sounds good! Feedback welcomed!