lens problem

[vintageslrs]

Folks

I got off ebay a package of 4 CS lenses (3 Mamiya and 1 Osawa) for the NC-1000.
My plan was to give the wide angle, telephoto and the Osawa Zoom to my wife for her NC-1000 and for me to keep the 50mm F1.4 lens for my 2 NC-1000's.
Well, anyone care to guess which lens is no good. And which 3 are perfect? ;D
So, the 50mm F1.4 Mamiya lens has an ugly stain or fungus or damage to it. It is under (at least) the first element...as I cannot clean it off from the outside element.
It looks like nothing I have ever seen before.I have seen the start of fungus before and this looks nothing like that. It is large streaky and has a bit of an oil slick look (prism effect) to it.
Seller says he doesn't remember it being there and he ain't gonna nothing about it. So I guess I will have to ruin his feedback and file a complaint with paypal.
But in the mean time, can anyone guide me thru a lens disassembly and re-assembly so that perhaps I can actually get at this stain/damage and maybe get it cleaned off?
Any help would be appreciated.

Bob

[John Parry]

Sounds like oil Bob - maybe someone has been too enthusiastic with a CLA. The Mamiya/Sekor M42 lens I have here doesn't have the usual slots in it for removal, so (if it's the same) you're looking at a soft(ish) rubber tool such as the piece off the end of a crutch or walking stick. If you can get it off like that try washing up liquid to remove the stain but WARNING - don't drop the lens in the sink!!

That's as far as I would go - if any more appears you are looking at a CLA by someone who has more skill than me. Sound like a seriously nice lens though, so probably worth it if you have someone local?

Regards - John

[vintageslrs]

Well, the spanner wrench I ordered from MicroTools arrived late this afternoon. I had already removed the ring and was ready to start removing the rest.
Well, the good news is that it all came apart easily and the oil stain or whatever it was ........was on the backside of the 3rd element. I cleaned it and it disappeared.
It is gone!!! Yay!!! ;D

So, this story does have a happy ending and many thanks to Ron Herron for his suggestions, recommendations and help.

Bob

[herron]

Glad it worked out OK, Bob! Bet you'll be glad many times over that you got that spanner wrench!