how to dismantle an atomic bomb... biometar 80mm P6

WolverineX · Last edited by WolverineX on Fri Jan 28, 2011 9:15 am; edited 1 time in total

or at least czj biometar 80mm pentacon six mount

first unscrew the nameplate

now you can see two metal rings, first unscrew the outer then the inner ring and take them out along with third ring

now turn the lens to the back and unscrew 4 screws,and take off the back plate

now you can extract the glass assembly out of the rest of the lens. you can remove the aperture ring but be careful not to lose the ball bearing.

if you need to clean inner glass you can unscrew front glass from the glass assembly

to put it back together, just go backwards. glass assembly has a groove you have to match with a small pin on outer shell of the lens and slide it in, then screw back the three rings in the front to fix the glass assembly to the rest of the lens, but you need to be precise to do it right, rings must screw in smoothly, if there is a tension or resistance then glass assembly is slightly tilted and you won't be able to screw the rings back...

Gonzoo · Joined: 29 Mar 2010 Posts: 231

Thank you WolverinX for providing this guide! It will prove useful!

Sami Loukiainen · Joined: 21 Jan 2011 Posts: 7

I Did this, but lost the ball bearing. Do you recall, what sort of a mechanism was that. I assume that there is some kind of spring underneath that ball bearing, but how big are those, the spring and the ball?

Attila · Expire: 2025-11-18

Title is funny but it is hide your valuable guide from search, please fix it to right one.

WolverineX · Posted: Fri Jan 28, 2011 7:13 am Post subject:

WolverineX · Posted: Fri Jan 28, 2011 7:14 am Post subject:

mo · Expire: 2016-07-30

Just use your edit button on the first post and you can change the title. Very Happy

WolverineX · Posted: Fri Jan 28, 2011 9:16 am Post subject:

indianadinos · Expire: 2011-12-05

Hi,

Thanks for sharing this nice tutorial ...

Cheers

Sami Loukiainen · Joined: 21 Jan 2011 Posts: 7

I went to a clocksmith. He found a spring from that aparture ring. luckily it had been so dirty that it has not fell of from that hole where it was. Spring is aprox. 2,5mm.
I also got new ball bearing from the same shop, it is 1mm, and works like a charm.
One thing that was weird, was that there were no thread on the other side of that hole, as the hole pierce the ring. Before I dismanteld my lens, there was a screw, but clocksmith said that there hasen't ever been threads. Our wise conclusion was, that it is intended for maintenance; adding grease.

Sorry for my poor english, but the point was clear?