Does someone know how to lubricate helical in Biotar 58/2

[koji]

My Biotar 58/2 is Exakta mount with aperture button sticking out.
The problem is helicoid of this lens is running out of oil, so focusing is
not so pleasant.

Point me to the some HP site of how to clean "Biotar 58/2" or
how to disassemble Exakta mount lense(s) please.

The reason for asking this is I finally got an Exakta->EF mount
adaptor from Hong-Kong. There is a small problem, but I can fix it.
But the lens is hard to crack it open.

[Attila]

I cleaned years ago my first Biotar 58mm f2 it wasn't difficult to open.
I think if you remove front ring labeled "Carl Zeiss Jena ..." after all easy to open it with spanner wrench . Rare side same thing with spanner wrench.

[koji]

Thank you, Attila.

I will try from the front.
(I was checking the rear side. )

[Attila]

[sichko]

This might be of help

http://rick_oleson.tripod.com/index-81.html