It does look like a duck call.
I cheated and hooked the vacuum cleaner up to my metal lathe and faced off three scrap end items with a parting tool turned at a 45, worked like a champ.
Since I have spent a lot of time grinding knives for wood working machinery I have somewhat of an edge on folks that have never done this stiff before.
I can also grind and sharpen the cutting tools free hand where I have seen a lot of folks need to use a jig or holding fixture.
My next step is to put some round tool steel in the lathe and bore it out on the inside to the right size and then cut or grind off one side and sharpen the outside.
I might have to heat treat it to get it to hold an edge.
Here is the old file I used to cut this stuff with it is enough to make a wood turner cringe.
Worth
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