The Post Pentax 6X7 300mm Repair Round-Up.

I had quite a time opening the front section of the forward group.  The lens is made up of a few sections and the front group's parts are the outer sleeve/barrel and the hood and inner sleeve/barrel as well as a hood that slides around.  The front and first element is easily removed via under the name plate and retainer.  The next two require the separation of the front group sleeves.  The spanner would be about 100mm wide and clear the third element which could be damaged by the attempt.  So I did get the thing open, but with a scratch to the inner barrel and lucky it can't be scene.  Inside the outer barrel was the first and second lenses and facing in is the retaining ring.  It took two and a half full turns to lock the element back in place.  In the optical world a millimeter gap would be a chasm and I think this was closer to two millimeters.  The ring was turned back in place and may need a thread lock to hold for a long time.  For now it is a quick fix as this lens will not be riding helicopters anytime soon.    How is the lens now?   It works nice!  First test was to sight-in using the city skyline just out the window.  I could see the tall buildings clear enough to see the antennas as well as the junk on the antenna.  The city being six miles away, so it was not a bad bit of glass performance.