Canon 50mm 1.4 ltm helical reassembly - HELP!

[bakemono]

So my lens was a bit 'stiff' and I decided to take it apart for some lubrication. Sure enough, dismantling it went quite easy, but now i simply can not put the helical back together.
The thread just won't engage, tried all starting points from both sides and it's just not happening, I've been at it for hours! If I had hair I would be tearing it out right now.

So there's just 2 pieces, I know they go together, I'm pretty certain they are oriented this way, but the damn thread won't engage!

I'm not 100% sure from which direction they should start the thread - either pic A or B?

Anyone has any tips or ideas?
Or am I rightly screwed?

 

[Art Vandalay]

Subscribed...want to take mine apart to clean/lube it as well.

 

[bakemono]

To test my sanity, I tried to disassemble and put back together another lens - fsu industar-61.
Of course, that one didn't have any trouble at all, engaging in any of the many starting points.

I wonder if there is something I'm missing....

 

[mpaniagua]

You could try contact the guys at this thread.

http://www.rangefinderforum.com/forums/showthread.php?t=105901

Probably they have an idea?

Wish you luck .... been there, done that 😛

 

[Waus]

Perhaps this helps:
https://www.youtube.com/watch?v=qMRnqIysGAk

Good luck!

 

[ferider]

Both will work. When you turn far enough A -> B.

The groove in the RF cam (the male part) has to be exposed in the end (will look more similar to B).

The threads have multiple starts. Just be patient .... hold the two parts as parallel as possible, reverse thread (clockwise) until it "clicks", then go forward (counter clockwise). And don't forget to lube first.

 

[Peter Jennings]

^^^^^ this

 

[Sarcophilus Harrisii]

Is there a bit of damage/wear to some of the thread starts? The middle photo shows what looks like a crossed thread and/or burred start? Hard to tell for sure from the pic. But you might want to clean those up, first, if this is the case.
Cheers
Brett

 

[bakemono]

I managed to do it!
Thanks for the tips guys 🙂 In the end it finally clicked for me at 2 in the night

The correct way to connect them is in picture A (but easier if you flip the whole thing upside down from how it is in photo)
Picture B will not work and should not work, as the helical is designed to stop when the threads reach that end.

The trick is, as mentioned, to hold them extremely parallel and in a straight line. If there is a slightest angle to the alignment, they won't start.
This is where photos or videos don't help much, you have to get a 'feel' for it.

I was twiddling the two parts for hours (got blisters on my thumbs), when suddenly they just effortlessly started.
This is another important thing, if you feel the threads 'bite' - they are stuck and the parts are not properly aligned, relax, twist back in opposite direction and try again. When they engage, you shouldn't even feel it. So watch out for the bite and absolutely don't force it.

There are 7 entry points for the helical threads and only one of them is the right one - trust me, I reassembled using all 7 a couple of times to be certain haha. You want the one where the little pin on helicoid registers at both ends of the groove in the part with the mount.

After lubing, the focusing action is about 3 times quicker. So as frustrating as that was, I think it was worth it.

I also adjusted the aperture spring to be less stiff, that one is a piece of cake in comparison, just unscrew the spring-holding screws a bit and push the spring upwards, there is a little play in the hole in the spring, so it's possible to adjust it a little bit, but it is enough to go from very stiff to very loose and vice versa. Do both screws one by one so you don't accidentally release and loose the ball bearing.

 

[Peter Jennings]

Congratulations! These lenses are a pleasure to use when you get the focus and aperture controls just right.

 

[ferider]

Congrats from me too. This is a cool lens, and the only fast 50 with 6 elements that I know. Some tests here, if you are interested: http://www.rangefinderforum.com/forums/showthread.php?t=155193.

Roland.

 

[Art Vandalay]

What lube did you use?

 

[bakemono]

I used some lithium grease.

 

[richowirawan]

What do you think of the lithium grease? How smooth is that?

I have a Jupiter 8 that I can easily focus with just 1 finger, it's super loose and I personally love it that way. I find my Canon lenses are much stiffer - considering to take it apart and re-grease the helicoid, but still not sure which lubricant that can generate the smoothness like in my Jupiter.

I've also heard about Moebius Oil...any idea?

 

[davidnewtonguitars]

I bought a container of lithium, synthetic, non-migrating helical grease for a few dollars, it should last a lifetime of lens lubing.


https://www.amazon.com/MicroLubrol-...=helical+lube&qid=1559396300&s=gateway&sr=8-3