Zeiss MK1 12mm T1.3 reassembly...

[charles g clark]

I’m posting this in the hope there’s a lens tech on here who can help!

i have the mk1 zeiss superspeed 12mm 1.3 as shown in the picture... and it’s in pieces. (Long story)

none of the threads are stripped, it’s greased and each thread goes into the other well but I can’t for the life of me figure out how to put the thing back together.

does anyone have any service information on the actual steps and markings etc to re assemble? I figure there must be a precise sequence to follow and I don’t want to keep wildly stabbing in the dark!

If it’s a send off job please let me know, I can’t see what I’m doing wrong and don’t want to damage any of the threads! Thanks in advance!

[Dom Jaeger]

Normally you would need to precisely mark each of the helical rings as you remove them to pinpoint which thread start to begin screwing them back into, as each ring has something like 10 different starts. You also need to measure the gaps at infinity so you know how far to screw each ring in.

If you don't have those marks, and you're not familiar with working on those lenses, it can be a bit of a Rubiks Cube puzzle to solve, and I would suggest sending it to a professional. Unfortunately it may take even a pro some time to get it right unless there are previous marks to follow.

 

[charles g clark]

Hi Dom

 

thank you for your reply! I figured they must be multi start threads - but 10?!! Ouch!

I think I’ll take your advice and send it in!

 

Hopefully it’ll stay in the realms of economic viability. Although quite likely it won’t given the relatively low cost of replacement these days but we’ll see.
 

Thanks again

[Dom Jaeger]

It’s been a while since I worked on the 16mm Super Speeds, but 10 starts is about right for the 35mm ones. It’s possible there are not that many on yours since the focus travel is less for shorter focal lengths. If you examine the rings you can count the starts.

Often a technician will have previously marked the rings, look for little V marks which you’d line up with where the index mark would be before starting to screw them on. 

You screw on the first double threaded  part until the infinity mark a tech made lines up (or the gap you measured before taking it apart is reached), then the guide ring then screw on the rear ring at the mark etc. 

But yes easy to get mixed up or cross thread etc so I think it would be best to have an experienced technician reassemble it.

[charles g clark]

Thank you again for that information Dom, it does appear to have some v markings so hopefully it’s do-able, fingers crossed!

But I’ll stand back and get a pro to look at it from here!

many thanks

Charles

[charles g clark]

Fast forwarding to almost a year later and having had the benefit of time and an uneconomically repairable lens, (by the time you add a PL mount and fix it, it didn't stack up), I managed to solve the Rubik's cube, put the lens together, remarkably without tearing up any threads, and get it all back, focussed at infinity (as good as my eyes can anyway) and understand the markings and gap measurements enough to rebuild it a few times....

Anyway, does anyone have any helicoid lubricant recommendations? I've tried NYOgel 795a but it seems a bit heavy for my liking (admittedly I might be packing the thread as well)

Needless to say the original zeiss lubricant would be ideal, but I believe you actually have to be a professional, trained lens tech in order to buy this (and rightly so, the complexities of even a simple prime like this is way beyond me) but since we are talking a rightly diy project i'd love to know if anyone has any recommendations

 

Thanks in advance!

[Dom Jaeger]

I think the original Zeiss grease may be a Losimol product. They make a variety of lubricants for applications like lens helicals and  sliding barrels:

https://www.losimol.de/en/products/#toggle-id-1

The Zeiss grease is creamy and grey coloured and very light, but does not seperate (leach oil) over time, which is important. 

[charles g clark]

9 minutes ago, Dom Jaeger said:

I think the original Zeiss grease may be a Losimol product. They make a variety of lubricants for applications like lens helicals and  sliding barrels:

https://www.losimol.de/en/products/#toggle-id-1

The Zeiss grease is creamy and grey coloured and very light, but does not seperate (leach oil) over time, which is important. 

Thank you again Dom, that’s amazing- weeks of internet trawling hasn’t even uncovered that brand! That definitely narrows down my search to a much much smaller area!

 

thanks again!

[charles g clark]

Hi Dom,

I have it all cleaned and lubed, back together and running smoothly until I screw the focus indicator ring back on- then it adds a huge amount of drag. It doesn’t appear damaged- would that ring also require lubricating?

 

many thanks again 

[Jean-Louis Seguin]

The focusing ring set screws are special dog-type set screws and they can only go in specific predrilled holes in the underlying ring. Never overtighten.

[charles g clark]

Thank you Jean - louis

I had a feeling the screws that came with it weren’t the right ones.

the holes in the brass ring do line up with the focus indicator ring so hopefully if I can find the right screws I can get it working as good as new! Think they’re an M2 screw, not heard of dog points before but a quick google tells me that’s what I need

 

thanks!

[charles g clark]

Hi all,

im back to tinkering with this lens again it’s becoming a bit of an obsession! 
mounting it on my sr3 I get a little bit of wobble which I think is due to this brass ring not being completely flat. 
I want to take it out and get it straightened and flat but cannot figure out how to get it out- any ideas?

 

thanks in advance!

[Dom Jaeger]

Hello again Charles!

That brass ring is to stop twisting play/rotation. It has no real role in whether the rear wobbles as such. The two keys slide up and down in the grooves of the lens body, keeping the body and rear rotationally locked.

If you have a wobbling rear section it will be because of wear/play in the focus threads. 

Thicker grease can sometimes help, but usually only rebuilding the threads with Emralon can cure that.

[charles g clark]

1 hour ago, Dom Jaeger said:

 

Thicker grease can sometimes help, but usually only rebuilding the threads with Emralon can cure that.

Thanks for the continued support Dom!

Deep down I believed that would be the case! I read somewhere that’s exactly what arri do with worn threads using emralon 330.

Now I do hate to give in, especially with this lens (my wife joked it may be the first time in history a lens has been cited in divorce papers), but I think I’m getting close to accepting it!

so my final questions- is emralon repackaged in a handy consumer sized spray can that you know of or is it only in huge buckets (as I fear) and is this even worth attempting myself?

thanks again!

[Dom Jaeger]

No, I don't think there is a consumer version. When I do it,  the Emralon needs to be diluted with MEK, sprayed with a variable nozzle spray gun in a booth,  carefully applied in layers on a turntable to get it even, and oven baked after each layer. Too much and you introduce tightness and have to lap it back. Took me a few years to get the technique right. 

There may be other products you could try that aren't as industrial.

[charles g clark]

Thanks again Dom

I’ve spent the morning looking into other dry film lubricants with ptfe which I believe the emralon is… I think this Lens has driven me to the point where I’m going to 3D print a little turntable an lad have a pop!