Kevin Purcell
Well-known member
My (second hand, as I'm in the US) Opticron Mighty Midget 1 twist focusing has just failed.
The outer portion of the EP rotates but is not screwing in or out to focus as it should.
I removed the rubber eyeguard to see if that was slipping (it wasn't) and can see that the collar around the EP is rotating but the EP itself isn't moving. It looks like this collar is held in place by three very small screws.
Digging out my smallest watchmaker's screwdriver I tightened up the screws to finger tight: one was quite loose the others not so much.
Fixed! The EP rotates and the focus works again.
Not sure I like the torque being taken by the friction of three small grub screws but that's the way it works.
Perhaps a touch of Loctite might help to keep the grub screws from rotating under their own steam.
Written up so it might help someone else fix a broken MM1.
The outer portion of the EP rotates but is not screwing in or out to focus as it should.
I removed the rubber eyeguard to see if that was slipping (it wasn't) and can see that the collar around the EP is rotating but the EP itself isn't moving. It looks like this collar is held in place by three very small screws.
Digging out my smallest watchmaker's screwdriver I tightened up the screws to finger tight: one was quite loose the others not so much.
Fixed! The EP rotates and the focus works again.
Not sure I like the torque being taken by the friction of three small grub screws but that's the way it works.
Perhaps a touch of Loctite might help to keep the grub screws from rotating under their own steam.
Written up so it might help someone else fix a broken MM1.
