How do I start repairing/cleaning/adjusting lenses?

[sdotkling]

I've got a few dog lenses that I'd love to try to fix up myself...like my moldy El Nikkor, or a dreadful old Petri 50. How do you learn to disassemble (and the all important re-assemble) lenses? Where do you find the tools? Does each lens require a separate tool? How do you clean the elements? Are all lenses sorta put together the same way? Where do the parts come from? These questions and more rattle in my brain.

 

[Phil_F_NM]

Lenses in-shutter like your Petri tend to be a little more complicated as the mechanism is coupled to the camera body. I really dislike working on fixed lens cameras.

Your EL Nikkor will be easy to fix as it has no focusing helicoid, just an aperture.

You need a lens spanner and a few very high quality screwderivers which will keep their edge for a long time. I use a set of French screwdrivers with replaceable blades.
Keep some small suction cups around as well as a pliable sheet of thick rubber for gripping lens barrels and unscrewing elements.

Solutions for cleaning should be naptha, denatured alcohol and pure grain alcohol. You can use something like WD-40 for rough cleaning of lens helicals but it leaves a residue and should be flushed with a cleaner like naptha.

If you soak a lens barrel, you'll likely lose the paint in the engravings so have paint available to refinish the markings.

Get some tweezers and a small stand (like the kind used for tying fly fishing lures) for holding delicate parts.

Very fine bristled brushes are used for applying small amounts of lube. Buy a bunch of good toothbrushes as you'll go through them quickly with some of the solvents.

Very aggressive solvents like denatured alcohol, acetone and MEK can remove some coatings, so beware.

Go to a watch repair shop and get some silicone sealant. This is very thick and you can either thin it with liquid silicone or add it to a product called SylGlide (available at auto parts stores) which is a non-petroleum distillate silicone lube used for bushing installation. This stuff is quite thin but doesn't evaporate and inside a lens helicoid can provide a good damping grease.

You'll need plenty of paper towels and find a work surface you can roll up and clean. I like using an automotive chamois. You need something that is going to not allow tiny screws to bounce. Also a few little trays or cups for your small parts. A silicone baking tray for tarts or cupcakes is an awesome part organizer.

Good luck and have fun!

Phil Forrest

 

[Robert Lai]

Get a digital P&S to document

Get a digital P&S to document

To Phil's comprehensive advice, I can only add that you should document all of your disassembly steps with a digital camera. A view of how components looked prior to your taking apart that next level.

With helicals, scribe a line across the alignment so you get the right starting helical.

 

[Richard G]

Phil and Robert, you almost have me wanting to service one of my lenses. This should be a sticky.

 

[Robert Lai]

Don't be so eager to DIY, especially if a leaf shutter is involved. I tried to service a Moskva 5 by myself. I couldn't get the slow speed train back in position without a spring constantly flying out. I finally had to send it to a well known repairman to put it back together.

"Who was the idiot who did this?"

(sheepishly)

"Me."

 

[alienmeatsack]

Phil pretty much covered it. I can tell you that the quality of your jewelers screwdrivers is paramount and do not skimp on them. The cheaper ones will lose their tip quickly, especially the flat head versions.

I also second Robert's suggestion to document with a digital camera. I personally do this when I do any work on electronics, cameras etc. I take notes and photos, making sure that I get more then 1 photo of each thing I'm doing for perspective.

I'd pick a lens you don't mind losing if something happens to start. Or, go find yourself some super cheap lenses at a flea market to practice on. Then have at it and good luck!

 

[Phil_F_NM]

Sometimes you just have to jump in and learn to swim in the deep end.
I nearly destroyed my Leica M4 when I was out in Iraq in 2004. I overwound the winder and stripped the brass shaft underneath it. Since there was no Leica repair in Fallujah in 2004, I decided to borrow a set of channel-locks from the machine shop (I was in a combat engineering battalion) and with my Swiss army knife and a set of jewelers screwdrivers, I took the camera apart and found the problem.

One of the machinists helped me make a brass shaft and then press-fit it into a collar and I was good to go. The only problem was that the winder lever return spring didn't have enough tension to fully retract the lever but the camera worked! (later on while in Spain, working with the public affairs center in Rota, I fell into the Bay of Cadiz and the camera was locked up with salt water. Sherry K. took care of it after I got back to the states and I still have the camera and use it once in a while.)

I digress!

It just takes a bit of courage to learn how these things work and you can do it. They were designed and built by people, just like you and I. Just go slow, keep records of which parts go where and in what orientation and you'll be fine. Just don't force anything. Be prepared to ruin a lens, so you might want to do your first tear-down on a thrift shop special instead of a regularly used or rare lens.

That said, I have fixed a few 21mm f/3.4 Super Angulon lenses and once I had the first open it was a revelation of simplicity. The worst lenses to work on are big, longer than 50mm Canon FD mount or the Nikon 85mm f/1.4. That nikon uses a double helicoid that is incredibly easy to get wrong when reassembling. The SLR lenses also have auto-apertures which add another level of complexity to the rear of the camera, while RF lenses have aperture controls up at the front with no springs or stop-down linkages which couple to the camera.

Phil Forrest

 

[sdotkling]

Gee, thanks! It actually sounds doable. I see lens spanners on e-bray, with several points. Assuming several would be more flexible. Jewelers screwdrivers are from $5 to $90 a set; I think I'll split the difference until I decide if I have any aptitude at this. Great idea about the photos-as-I-go. I just may try this. The tools don't cost much more than a lens CLA (maybe a bit, but still...)

 

[Landshark]

FWIW, Japanese cameras don't use phillips screwdrivers. They're called "cross point" and don't have the same angle on the tip nor to they have a sharp point like Phillips.

Microtools is a good source of tools that aren't going to strip under hard use.
I haven't found a set of Chinese drivers that were worth the energy of opening the box.
Most local hardware/big box stores are not going to have quality products.

 

[gb hill]

One other thing you will need. Good eyesight at close range😀 or a good magnify glass. The kind you can look through while your hands are free to work.

 

[Robert Lai]

Even if you get good screwdrivers, you should consider sharpening the flat-head points. Most are too wide to fit into the screw head slots as they are. A few minutes on a whet stone with a bit of oil will do wonders.

 

[sdotkling]

Microtools! Eureka! That's the source. Thanks!

 

[Phil_F_NM]

Oh yeah, find a set of LED illuminated stereoscopic watch repair spectacles. The big green kind with the flip down lenses and ratcheting headband are almost essential. I use mine so much I don't know what I'd do without them.

Phil Forrest

 

[ZeissFan]

The Summitar has two sets of aperture blades. Each set is shaped slightly differently, and must be alternated during assembly.

Replacing aperture blades is an exercise in patience, taking roughly 30 minutes and very steady hands.

A brass-bristled brush is essential for cleaning certain parts. Brass removes grim and other debris but doesn't scratch surfaces (when used correctly).

Find Thomas Tomosy's book on camera repair. It offers plenty of good advice, including a section on cleaning lenses.

By the way, dishwashing soap and a soft-bristled toothbrush can remove grime and oily debris from top decks and other parts without damaging anything.

 

[maddoc]

To the mods, can`t we have this thread make a sticky ? Such a wealth of valuable information.

 

[farlymac]

Check out some of the lens repair photos on Flickr too, for a quick lesson on tools and techniques. And sometimes what not to do.

PF