Hello,
The horizon mirror of a Tamaya sextant which I recently borrowed is not straight: The boundary line which separates the coated from the non-coated half is not parallel to the sextant frame, see the area circled in red in the pictures attached of the front and rear of the horizon mirror.
How am I supposed to straighten up the mirror?
Thank you! 
I have exactly the same problem with a Tamaya sextant I just bought
The seller provided instant support, you can rotate the circular mirror by hand in it’s frame,
I was just a bit nervous about doing anything I wasn’t sure about.
I now have a beautiful new-condition zero non adjustable error Tamaya 633 at the fraction of the price of a new sextant such as an Astra.
Got it from a seller posting on this forum
If you want a contact PM me
