Open a lens to cleaning fungus question

Hi..

 

I already open one of my lens to clean some fungus but now I have another one

that badly needs a cleaning but can't unscrew the front glass. I called Nikon to

ask for what tool they use and they told me that I shouldn't open a lens because

they need a very pricise calibration that can only be done by them.

OK. I did it once with a AF ZOOM lens and the lens works no problem and the only

tool that I used was a screw driver.

 

OK.. I have two questions about this:

 

1- you know what tool I need to unscrew the front ring to take the front glass out.

2- I got lucky the first time I cleaned a lens? anyone here also open there lens

to clean it and if so can I get some tips.!

 

Thanks for the inputs

 

Juanjo

by the way, the lens in question is a Nikon 180mm 2.8 AI and I'm going to also open a Nikon 300mm 4.5 AI as well.

 

Thanks

1) I don't have my 180mm in front of me, but will it take a spanner wrench?

 

2) I've read on these forums that fungus can spread to other lenses and equipment, but you might want to find out for yourself.

 

3) I've got a good friend that used to work for Nikon (corporate) and has a whole series of special jigs and tools to take apart lenses and put them back together again properly. Yet I hear of people doing this on their own and cringe because there's just no way you'll get them back together the way that a Nikon repair station would.

Most Nikon lenses can have the groups removed intact. Reaching for a spanner wrench first is almost always a mistake and the sign of an amateur lens butcher. Fungus usually happens on the accessible inside surfaces of the groups, not between the individual lens elements. It's usually not a big deal to get the groups reinstalled without compromising performance. That isn't the case if you remove individual elements. They all come apart differently, but many let you remove the rear group by removing the mount for access to additional screws. Others can have the front group removed by unscrewing a ring, but you really need a diagram from someone who's done it before. I don't have any experience with the focal lengths you mention.

Aiii! If its a 180mm Ai with a thick 'square' chrome ring, or a 180 Ai with more of a Ais ED

180 makes a Huge difference. The older thick 'square' chrome ring P 180mm Ai is a very

very tough lens to do work on. This lens is an overbuilt tank, with Tons of precise set

screws, a very very hard lens to get to the fungus to clean it.

Sure, you say, since you did an AF Zoom and that was easy (don't say which one, some are

easy and some are hard) but let me tell you, you haven't seen anything like the internals of

a thick 'square' chrome ring P 180mm Ai. If its like the later Ais ED with the smaller

thinner 'round' chrome ring it *may* be a bit easier, that particular subtle 'cosmetic' lens

change Pre-ED Nikkor is one lens I haven't done, but I've done an Ais ED as well as 2 thick

chrome ring P lenses and one was so difficult it became the parts lens for the other one,

which was only slightly (and I mean slightly) easier to work on. Probably due to the

learning I did on the first one and the second one was so photojournalist worn-out the

screws were loose (er).

If your lens is in decent shape execpt for the fungus, send it to the oldest Nikon shop

around, there may still be somebody alive that knows the tricks to working on it. If not,

either you live with the fungus and deal with that or run the 90+% chance of ruining

(DEstroying) the lens by attempting to fix it.

If you decide to attempt, contact me and if its one of those, (and your really really want to

try it) I'll see if I dig up the old carcass to help to get started. It will be tough, this lens is

about 9.2 on a scale of 10 in terms of repair.

The front lens element should just pop off using a spanner, as others have said. If it isn't too tight just a jewelers screwdriver will work. If you have to go deeper into the disassembly, Nikon is right that you need to realign the lenses. Again, the front lens just pops in place on just about all of their models, so no adjustment is needed.

Forgot about the 180 square ring. Could be trouble. There are set screws under the outter ring, 3 if I remember. Send an email to Christiaan. I haven't repaired one in over 10 years. It's a good lens to fix.

This is the lens I have http://www.photosynthesis.co.nz/nikon/ai18028.jpg and the fungus seems to be in the front..

Already open the back of the lens and made some basic cleaning, I can see the fungus after the aperture blades so it must be in the front. but the front ring is very tie and look like I going to need help there.

I was thinking on getting this tool http://www.amazon.com/Lens-Spanner-Wrench-Camera-Enlarger/dp/B000HRD0K8

 

Anything I should know about this lens before open it..?

www.micro-tools.com

 

http://www.micro-tools.com/store/SearchByCategory.aspx?CategoryCode=LNS

 

The gum rubber tools at the bottom of the page to remove rings without using a spanner which can cause damage.

Thanks for the rubber tool idea...

I called them and they have all the sizes but mine (72mm)

Any idea of any other place I could get that tool..?

 

I did some google search but no luck.

 

Thanks.