Canon 50mm/f1.8 CLA

[chendayuan]

here are the arrows point to the retain ring that hold the focusing helical. I campared Canon 50/1.4 Leica 50/1.5, optical Canon is better, build quaility, Summarit is much better.

by the way, I upload a Canon 100/3.5 picture
http://www.rangefinderforum.com/photopost/showphoto.php?photo=16540&cat=3209&page=1

 

[Sonnar Brian]

JLW: Yeah, that's what I did last year...

How about moving the pictures and associated instructions the a thread on the repair forum. I'm going to start doing that as well, my Lynx repair will be a thread as soon as my head clears from this blasted summer head cold. It sure beats the best dumb look method every time I open a lens up.

I'm just going to add that these lenses are probably 30 years past their design life. Some have seen a lot of use. I doubt that anyone will be having these conversations about the plastic computerized acrylic element wonder-zooms of today in 2055.

 

[blee017]

I found that the aperture control mechanism on the f1.8 is exactly the same as the f1.4 jlw showed.
The only difference is that the front element of the f1.8 is held in place by a retaining ring (rather than the whole front group screwed in).

After removing the brass ring (very carefully), I could lift the aperture ring.
With a bit of synthetic grease applied, now it turns smoothly.

Thanks a lot!

 

[CZeni]

Well guys, I used the info here to clean up a $75 Canon 50/1.4 I picked up earlier this week. It was grubby outside, but not beat up...a little bit of scraping at the filter threads, that's all. But inside there was fungus. Not a lot, but any is more than I wanna let be. With the info here, I opened up the lens and got the fungus cleaned up - no etching! Cleaned up the exterior, and now I have a clean 50/1.4 with zero cleaning marks.

Question - recommended grease for the focusing helicoid? This one's a bit dry.

Thanks!

 

[back alley]

75 bucks?

that's a sweet deal and now a clean one too.

joe

 

[jlw]

Question - recommended grease for the focusing helicoid? This one's a bit dry.

You might try disc brake caliper grease (from an auto parts store.) I've used regular white lithium grease as well, and have had no problems, but have read that it sometimes separates. What's good about the disc brake grease is that it's designed to withstand very high temperatures without breaking up.

BTW, don't just smear some new grease on the helicoid -- first clean out the old grease thoroughly with solvent and a toothbrush. Henry Scherer uses an ultrasonic cleaner on Contax parts, and I've always wanted to try this, but haven't done it yet.

 

[Wayne R. Scott]

I think white lithium grease by Loc-Tite is highly recommended.

Wayne

 

[chendayuan]

disc brake caliper grease (from an auto parts store.) is better. nowhite lithium grease

 

[Brian Legge]

Are you also trying to relube the helical, or just repair the sticky aperture?

Just to mention, on my Canon 50mm F1.4 the aperture ring itself was the culprit. All those years of skin oil and dirt from being handled must have built up. Used a little isopropyl alchohol on it, freed it right up. No disassembly was required. This may not solve your problem, but it is easy to check out and probably should be done anyway.

Oh, wow, you just saved me a lot of headache. I picked up a cheap Canon 50mm 1.8 which had a stiff aperture ring and a little oil on the blades. I was convinced the oil was causing the stiffness. I'd gone as far as removing the optics module once but ran out of time to work on it.

I stumbled across this post comment this morning and tried it. The ring freed up instantly. What a nice surprise! 🙂

 

[Sonnar Brian]

Google is our friend, and it is funny how these old threads pop to the surface!

My Canon 50/1.4 aperture ring still turns smoothly.