|Posted: Wed Feb 15, 2017 1:14 pm Post subject: Meyer optik Gorlitz Trioplan 100 f2.8 tutorial CLA
|A few cautions: although it s an easy lens to work with, do this at your own risk. My lens has a M42 mount, if yours has a different one, than this tutorial can only be taken as a general guide, since the assembly may be different.
Please read the whole tutorial from start to finish a couple of times before you do it!
Although i worked on the optical block i did n t want to include it in this tutorial, since it s better not to touch it becouse of a few spacks of dust inside!
The explenations in the tutorial are meant for begginers, more experienced people need to be patient, the tools that you ll need are a 1 mm flat screw driver and a bit larger one, cleaning liquid and grease.
Set the lens to infinity and keep it there! One little tip, use a caliper (hope it s the correct name) to measure the lens, set to infinity (a digital one is much better) this is one way to make sure you put everything back in the correct way This can be done at warious steps during the CLA.
There are 3 different levels (parts) how far one can go in this tutorial, the first and easiest one is to simply separate the part that contains the optical block from the part that has the focusing mechanism. A word of caution, if you can t unscrew the two parts with some reasonable force, skip this, to much force will introduce play in the focusing mechanisn, as you ll damage two "pins" inside the focusing helicoid! Also you can do this at a later stage! Even if you do this it probably won t be enough to do a proper cleaning and regreasing. Most can skip this part. Grab the front and rear of the lens and unscrew it, counter clock wise.
Be careful that you don t grab both parts with one hand! I am showing this step only because for some this will be enough to do some cleaning or relubing. You have now acess to on part of the focusing helicoid:
Absoulte begginers can try to add a drop of "oil" if the old grease is dry, i use Krown oil, do not use WD40, lightning fluid or other stuff, use a brush to applay minute quantity and turn the foucusing, repeat as needed. Be careful not to over do it!
Most will want to go further so proceed to pat 2 by putting back the two parts (no need for that if you skipped the first part) and untightening a small screw at the back ring
You ll need that 1 mm screwdriver
I usually don t remove the screws whwnever possible, simply tighten it back, make sure it s stabe inside and place it away.
Next remove the 3 screws at the back of the mount
Once removed pull up the mount straight , try not to turn the ring while doing it!
It may be a good idea to take a picture of the helicoid before you start to turn the focusing ring, as you can see the infinity mark is alligned with the red triangle on the front black ring.
There are two holes with a brass "pin" each, these are delicate and can be damaged if you applay too much force to separate the fron and back of the lens as shown in the first part! Difficult to see but here they are
Next turn the focusing ring counter clock wise, slowly, the two "pins" should come out on their own
Keep turning until it s time to remove a spacer ring
Now the most difficult part, the thread of the focusing helicoid has more than one step so it s very important to know which is the right on when putting it back. To avoid guessing we have to remember where the focusing ring separates from the helicoid. On my copy taking as a reference point the infinity mark this happens when the mark is alligned with the red letter "V" on the black front ring! Yours may be different, if you don t have any reference points, you can "mark" it with a screwdriver.
Get this step right and everything will be fine. If you loose the reference don t panic, the thread is fairly large and there aren t too many steps., you ll just have to find the right one.
Remove the two "pins"
For easier cleaning you can now remove the focusing helicoid, turn it counter clock wise, this is a better way to do it than the way described in part one.
This is only one part of the focusing mechanism, we have this part also
Like at the beggining you may try to relube it without dissasembling it, there is some space between the two rings after you turn the back, this time clock wise
But it s better to dissasemble it, remove the screw on top
Another tip (you can use it for the focusing ring also), sometimes i try to tighten the part i have to remove all the way down, this way sometimes it s easy to find a reference point, (or you can measure them with thecaliper), in this case one of the holes alligns with the infinity mark
With this lens you can actually skip this part and just remove the back ring, it comes out at the infinity mark
and above all there is only one step on the thread, so no problems to put it back! So now we have all the parts dissasembled, clean them (i use withe spirit) and lube them. This lens needs little grease, in particular the rear part, as the threads are very fine. I did a CLA on this lens few months ago so the grease that you see in the pictures is "new" frease, and this amount was enough! One suggestion: use some of the old dry/hard grease on the two slots in the helicoid thread, where the tow pins go in!
Time to reassemble the lens! Put the back ring into the focusing ring, it s a left turning thread so counter clock wise to tighten it, and again there is only one step
Be careful not to position the screw between the two stop pins, so to infinity and then back a little, then tight the screw.
Next the focusing helicoid, It has only one step so no problem to put it back but a caution note again, this needs a lot of force at the end or the two main parts of the lens might be slightly missalligned at the end, on my copy they where by 3 or 4 mm, the only way to tighten the helicoid enough was to put a bit of polishing paste on the thread that tightens it to the optical block (not the thread on the helicoid itself) and by tightening and untightening i was able to tighten it enough to allign everything! To make any sense of what i am saying, look at the slot on the thread and the f2.8 on the next picture.
on my lens the slot and the f2.8 marking needed to be alligned perfectly.
Next the most delicate part, putting back the focusing ring
Allign the infinity mark to the letter "V" and try to find the step on the thread by truning the focusing ring left and right a bit. Take it easy, take time, do it slowly, at first this can be difficult as the focusing ring wobbles a lot and it s not easy to find the step. You migh try to put them together on any step first, just to get the feel.
Once the focusing ring is on turn it all the way down, then turn it back for about 1/4 of a turn to allign the holes to the slots, if you got the right step on the thread everything should be alligned perfectly.
The two red triangles and the infinity mark and of course the holes to the slots, if so push back in the two brass pins. Not shown in a picture put back on the spacer ring before putting back on the mount ring, make sure the two "pins" are really all the way in!
Allign using the infinity mark and upeer triangle, put back the screws and tighten them. You may now try if the lens reaches infinity on a camera, if that s the case put back the last ring
If you left the screw inside remember to untight it! At first there might be some play in the focusing mechanism, this is due to the to brass "pins" and the slots in which they travel, as suggested before, try to use some old or very sticky grease in the sloty. IN a couple of weeks as the grease dries this play tends to go away.
And that s it!