1890s Antique Willcox & Gibbs Sewing Machine w Motor base.
Whoever put this one together did things s bit differently.  They put the motor to the side, and had it rub against the lower piece.
There is rust and wear with the bottom turner.  Everything moves up and down.  I have not tried the motor- did you see the plug?
I cleaned a bit of the chrome metal.  There seems to be a piece missing where the thread goes.
Please see pictures and ask questions!