Thank you Patrick. I appreciate the interest and kind words.
I did my sinew/ hide glue wraps and will post pics soon. I still haven't decided how the handle will be done. I am leaning toward cordage for a handle wrap.
Lessons learned:
Shell freshness matters. I placed my 15 shells on a 1/2" dowel (13mm) uncemented, and rubbed them over a sandstone rock. This worked well for sanding and grinding. From time to time an edge would flake off taking a layer off with it. Below is a picture with break points identified on the eight I chose to finish with. I truly think this happened because a few of my shells may have weathered for part of the year before I came along. When I first started, any shell that flaked off a layer while I was cutting out the rough blank was discarded. I thought I had only good blanks but i think a few still got by me. If ever do this again, my intent is to work with shells that show no sign of deterioration. The dark black/green pigment layer on the outside can't be flaking off even a little. Don't get me wrong I like the final product but those little details catch my attention. This has been a lot of work and I want to be proud of it. I intended to only make one mussel shell weight replica like this. This one may have been my practice run. I really want an authentic mussel shell atlatl weight.
At some point you have to commit to adhesion. While rubbing this stack of shells over the rock I had trouble sanding them on their triangle edges. Why? the shells would rotate slightly at irregular intervals making it hard to give them all the same shape. So i either had to use hide glue to keep them in place temporarily, or just use the pine pitch glue or asphaltum adhesive. The bottom line was the shell segments can't move while you are giving them the final shaping and sanding. What this meant was I had to step back from my notion of gluing in 8 finished shell segments and glue in partially done segments - then finish them in order to get the look I wanted. Not an earth shattering lesson, just something I note for future projects.