calling all Rokkor experts

[vintageslrs]

Can one of our Rokkor experts tell me the best way to get to the 2nd element from the front of a 58mm F1.4 lens?

thanks much
Bob

[Peter S.]

Hi Bob,

I would try to get some inspiration from here:

sa-ss.hp.infoseek.co.jp/index1.html

This is the best place I know. I've been in the MC W.Rokkor-HG 2.8/35 (success) and in the
MC Rokkor 1.9/55 (pretty identical to the MC Rokkor 1.7/55 - spring broken during disassembly
that presses the tiny ball into the aperture stops). These lenses should look like the
MC Rokkor 1.4/58).

Good Luck! And best regards
Peter

PS: not much time to spend here anymore - need to look for a new job :-(

[vintageslrs]

Thanks PeterS.


All I really want to do is get to the element right below the front element....if I can do that without removing all the rear elements, that would be ideal.
There is a spot of what I assume is fungus on that 2nd element from the front one---just wanna get at that and try to clean/treat it. It is a lens that came with a recent purchase.
Any suggestions would be appreciated.

thanks
Bob

[Peter S.]

Hi Bob,

on the site I referred to it is shown how to unscrew the complete front element. I'd start
in this way. Obviously I would not remove the aperture mechanism as for less
experienced lens mechanics this easily can result in difficulties to get the thing reassembled
(not to speak of the high probability of loosing the tiny steel ball).

I would then disassemble the front element from the first element going deeper. The construction
code is PF - 6 elements in 5 groups, and I think three should be three individual lenses in the
front group. I.e. unscrewing the holding ring for two lenses will be enough to completely
disassemble the front group's elements.

Of course You could also try to individualize the lenses from the mounted front group - but
unscrewing the front group seems to be simple for all these older Rokkors - so I'd start like
that.

Best regards
Peter

[Peter S.]

PS: prior to removing any screw, I'd loosen it a bit and carefully check, whether it really holds
the part I am about to get off. It is also wise to mark all tubes and rings that might have to
do with focus or aperture control - just in case You unscrew them unintentionally, then You have
a fair chance to get it back without the need to readjust anything.

[vintageslrs]

Hi PeterS

I read the instructions on the site and looked carefully at the photos...but as is often to case for me--I cannot get the first step accomplished. I do not have a rubber tool like shown. I tried using a rubber kitchen glove to no avail.
So I cannot get that original Minolta decoration ring off---and without that done---I cannot go anywhere.
Any other suggestions?

a frustrated Bob

[casualcollector]

Frustrated Bob,

Go to the local Aubuchon hardware store. In the aisle that has the little drawers full of screws, nuts and screen door hardware is a drawer full of black rubber stoppers. The #10 stopper is about 42mm at the narrow end and 50mm at the wide end. Grind some of the rubber out of the center if the glass of the front element protrudes too far. The whole front group of three or four elements should unscrew as an assembly. I haven't had to go further than that.

Bill

[vintageslrs]

Bill

Thanks much...we have an Aubuchon's next town over..so I will get one probably tomorrow...and have a go at it.

thanks again
Bob

[vintageslrs]

Bill and PeterS.

I went to Aubuchon's today- bought the correct rubber O-ring and tried and tried to get that trim ring on the front of the lens to move----no luck...still can't budge that @#&*@* thing!

Any other suggestions?

thanks
Bob

[Peter S.]

Then I'd carefully drill two 1.0mm holes into the opposite sides of the ring. Use a sharp needle to
prepare a small round mark so that the drill won't run away. It might be best to fix the drilling
machine and move the lens. All in all I would expect the ring to consist of pretty soft aluminium.
You should be able to move the ring by getting into these small holes.

Sorry, this is the hard way. ;-)

[mickeyobe]

Bob,

Before attempting anything drastic that might compromise the value of your camera try this.
Put a drop of lighter fluid on the very top edge of the retaining ring where it meets the lens barrel and another drop on the opposite side. Wait a minute or two and then try your rubber bumper again. It might work its way between the threads and act a a lubricant.
It can't hurt and it might work.

Are you sure it is not a reverse thread?

Mickey

[vintageslrs]

PeterS

Oh boy! Not sure I am up to that challenge .

Mickey

I will try that...and yes, I am sure it is not a reverse thread.

Thanks Guys
Bob

[Peter S.]

Hi, no it is an ordinary thread. The same as for the filters.
Yupp, try it with the lighter fluid first.

P

[vintageslrs]

Sorry folks.....lighter fluid did not help.

Maybe I can get a very thin bladed knife between the trim ring and the body of the lens and sorta pop it out of the threads?


Bob

[mickeyobe]

Bob,

Before you slice the camera or yourself like an 8 year old cheddar please try one more thing.
Cover the glass with a tissue or cloth and try applying to the obstinate ring in the same manner as the lighter fluid some WD40. Make a little puddle of it in a bottle cap or thimble or watch glass and apply with a needle or toothpick. Then wipe away any that might be on the ring and, once again try the rubber bumper.

As you can tell, I really hate to see a camera or TCC member mutilated.

Mickey