Following notes are results of my hobby work with my RTS II. I tried to write all you potentially need if you have to do (want to do, willing to do) the same repair. All the information are "as-is", since I'm not qualified repairman – but my RTS II is working fine and looks nice. If you have specific question, you can contact me via email (delete underscores from start).
Painting body cover
Painting job is much easier than replacing curtains, but it's a not piece of cake either. I will try to cover my process of refreshing look of camera body.
I bought second RTS II in bargain condition to supplement my other cameras as a backup body. However, I liked the look and handling more and more, so I decided to fix unpleasant look of the camera (brassing, dents etc.)
What you need
- Buy good screwdriver if you don't have one ("+" type)
- Pieces of thick wire to hold parts away from you
- Black paint (more on this later)
- White matte paint (or mastic?) paint for labels
- Ochre (Yellow tone?) one for letters, pick up the tone you like
- Solvent, like Acetone, for cleaning *metal* parts, for the rest use lens cleaner
- Smooth thin paper
- Piece of wood, small and bigger one, as required, and a small hammer (preferably)
- Some quiet place
- See next chapter about shutter curtain for more ideas
What you need to disassemble
Basically, you can rather easily remove top and bottom covers, plate below lens ring and back doors of camera. Back doors are probably the least annoying job – just pull the trigger on door axis and it's done. Keep it in very safe place, however.
There are some obvious screws and some hidden traps:
- You may leave flip for blinding the viewfinder at place, no problem.
- ASA speed dial has a small "dress screw" at the top. It has no guides for screwdriver, I think small piece of rubber or rubberized "anything" should work. This is a normal screw. Rest is easy, and you can (you have to) leave under/over exposure and main switch at place (so far)
- Advance lever also has "dress screw", this time with different thread! You have to turn it right (clockwise) to unscrew. Under it is another big screw, also with opposite thread.
- Remote shutter socket has another dress screw – thin cylinder, I'm not sure, how I managed to unscrew it, probably with finger or small piece of wood. Thread is normal.
- Rewind knob is hold by the peg, which itself inserts into film cassette (the "U" shape upside down). You have to insert screwdriver or similar tool to the gap to keep it and turn with rewind knob (in opposite direction than rewinding the film – i.e. thread is normal). Remember to remove back of the camera now, since from this time there is no simple way how to open it again :-)
Rest should be easy. Once you remove also small screws, you may remove top cover. Take care about anything what might fall from inside – there is a small metal peg just under the shutter, for example.
You should remove the main switch and under/over dial, there is a spring around them at the bottom, you need tweezers to remove it (be careful – otherwise prepare for search mission)
You can remove shutter and lock button for shutter speed dial, but also you can just cover them with something like chewing gum (special kind, not toooo adhesive, it is possible to buy it in paper store, I assume. It is intended to keep small papers on wall)
You may remove also the flip for viewfinder blind, you would need scissors to do this.
Take special care about the flash hot shoe. There is a piece of metal which puzzled me, because there was no screw to hold it. Apparently it holds in place itself, stuck on metal pin! You need to use some pressure to get it back in place. Actually I think it should remain there, but mine for some reason fall away. If no parts are falling or disassembling, don't do it by yourself :-) Generally, there is a logic behind those metal pieces and you should be able to figure it out. There is a small black pin pushing one contact so when you insert the flash, it moves and shorten one part of circuit. Other two are (probably) controlling flash output itself. Just be careful and look for any part which fall from shoe, save them in safe place and play jigsaw later.
- Bottom cover is easy to remove, there are three screws at all. The middle one is shorter than others, keep it in mind when assembling again.
- Watch for the battery and a cover for motor drive contacts. There is also a washer on motor coupling.
Front lens mount "undercover"
There are four screws holding metal bayonet. Under it there is a metal cover, which is also easy to remove (there is some glue keeping it in place).
I tried to fix small dings using small hammer and a piece of hard wood. Same wood should be also used as a support – smooth, of course.
I also cleaned the viewfinder piece, it's easy to remove the blind, but if it's clean, don't bother. As a cleaning solvent I used Polaroid lens cleaner – you have to use cotton two or three times to succeed.
You need to carefully clean every piece before painting – with some solvent, like Acetone or similar one. There should be no remains of cotton nor dust. Don't try to remove old original paint, since it is very resistant, like the paint on car shell. But if you know how to do it and want it to be plated in gold instead, you can try.
Prepare some quiet place :-) for dealing with spray. I don't advice outside, since even small wind is very annoying. But take care about the fresh air! Also cover everything which might appear in front of the spray, like business clothes.
I used pieces of thick wire to keep everything during painting – when properly curved, it even holds small parts like screws (just create a small eyelet and use it like a spring). As for paint itself, I went to several big stores, nothing special, and bought some black paints. The best one, almost perfectly matching was "Decospray black semi matt" (matte satin?). Trade mark is probably something proprietary to Tesco stores :-) point is in "black semi matt", I guess. Try several by yourself, it's worth looking.
Wires for keeping parts are also useful to put/hang/store painted parts somewhere. You can insert it into small hole, for example, or to various gaps.
Start spraying outside the piece and then carefully go across, stop again outside – during start and stop phase, spray is likely to produce annoying drops. Do not hurry. If you spoil the first job, remove the paint with solvent and try again :-) I had to remove my previous painting since it wasn't up to my expectations.
Once they were dry (some 8, 12 hours) I used white matte paint (small package for hobbyist) and very small paintbrush to paint white labels. The white mastic could be probably better, but I was unable to find proper one. It takes three or four layers, actually. I put the paint carefully into recessed numbers/letters and used piece of smooth paper (you may need to find out which one is appropriate in your country) to remove excessive paint. Just press your finger on paper like you are cleaning lens filter, this way the paint inside the indentation won't be affected. Wait a few hours, repeat painting. I found out that greasing the outside of numbers with my wet fingers is a great protection against unwanted painting and ended up with removing excessive paint using just my fingers :-) As you can learn later, trust your fingers more than tools.
I also fixed white numbers on shutter dial and ASA dial. I tried to find the same ochre paint for the rest of dial, so far I used slightly more brown paint. I cleaned carefully other items, like self-timer lever, mechanical exposure lever and AE lock and applied white paint where appropriate.
Reassembling should be a piece of cake, since there are no important mechanical parts involved.
Repairing shutter curtain and related stories for everyone interested
First of all, if you are short of time and tools and can buy another RTS II, go for it. I did my repair as a part of "technology vs. human game", and I wanted to win. But I spent probably a lot of money and time ineffectively… I don't mind, since I have gooooood feelings now.
Another option could be authorized Yashica service. There should be some repairman certified for camera disassembling. Service in Czech Republic is too far from my home and moreover had the same opinion as I above.
Secondly, even with all the description below, repair manual, proper tools and skills etc. etc. you need a bit of luck to succeed. I made two BIG mistakes, but I was lucky enough to fix them. I suppose you will have such heart-breaking situations also – again, if you want to avoid your psychoanalyst for next few months, just buy another camera body. But if you enjoy Sierra's "Incredible Machine" game you are already prepared.
- Good screwdrivers. I mean really good screwdrivers. You will need the cross (+) one and small normal (|), and for some special screws also bigger one, but it's less of a trouble. Avoid advertising sets of five or six small screwdrivers, they are just for fun or to fix glasses, nothing more. I've bought two Molybdenum–Vanadium (3mm width) with big handle. Remember, if you scratch some screw and are not able to remove it, there is almost no way how to fix it!*
- Small spanner. I didn't have one, I used small nice (monkey) wrench. It is necessary only when removing parts around shutter speed dial.
- Good adhesive (glue). I bought several of them, but without testing I tried the most expensive one (actually Cey's, based on ethyl-kyanoakrylate) and it proved to be worth the money. It takes few seconds to fix curtain, which might be advantage – or disaster. For attaching cover leather I used different one – flexible glue, so it will hold even with tight handling. (you probably can get leather replaced by Yashica service, but I didn't bother). Try both of them on some unnecessary items ready to be thrown into trash.Be careful about you fingers, eyes etc! Some glues are very dangerous and you can end up with your fingers fixed to camera or knife or anything else. In such case, use hot waterimmediately, glue will polymerize in different way and free the tension. It's better to look like human than screwdriver-nailed-creature.
- Have the original repair manual ready. I don't think it's possible to finish all the tasks without it. Anyway, you have only one body to play with, right? So I will assume for the rest of this story you posses such manual. I've bought mine on eBay, for example.
- You need solder. Create small soldering eyelet. Use thin wire instead of traditional thick one. Thick is good enough for fixing power cord, however, tiny electronic parts require small and fast reacting solder. If you want me to be specific, mine copper wire was 0.75mm thick and about 6cm long. Pre–heat solder away from contacts, be fast when unsoldering and use tweezers to keep parts in the right place and deviate excessive heat.
- Prepare A LOT OF PATIENCE.
Good to have and know, not necessary
- Buy several small pouches, preferably transparent with lock along the opening to collect related parts together. Use black permanent marker to write labels on them, like "screws for ASA dial, fig. 12".
- Cover table with white paper. I joined several sheets together with adhesive tape. It makes looking for parts much easier, moreover, you can make notes directly on the table :-)
- Trust your fingers more than your tweezers! Tweezers tends to play ping-pong with small screws and looking for them on carpet is time consuming.
- Very useful are adhesive labels, like labels for floppies. I stick them to table upside down and put current set of small parts on them, so they don't fall off the table and I don't need to worry where they are.
- If there is more than one screw to keep specific part, insert first one and screw it, but do not tighten. After you insert last one, tighten them all.
- Remember, you may need to remove this part again! (Don't ask me how many times I had to remove shutter speed dial – MANY times)
- Make sure you have all the parts assembled. My first trouble arose, when some wire holder fell into winding mechanism and stuck it. Watch if all the parts you took from the bag are on their places. If there is some not fixed washer, take care. Maybe it's not 100% necessary, but…
- Small piece of rubber is also handy, because some screws can/should be removed only by hand – the dress screw on advance lever (left thread!), dress screw on ASA dial, small ring around electromagnetic release socket.
- Don't remove anything if it is not necessary! Sometimes putting things back requires fairy good amount of adjusting and can be annoying. This applies for example to curtain adjusting plates – for fixing first shutter curtain I really didn't need to remove them. I had to play with them for more than one hour to adjust curtain properly again.
- Pay attention to ALL texts in manual. Sometimes there are small notes, but important ones.
What is not in the manual
There are several thing the manual doesn't contain. I don‘t know why, but since you are not supposed to do certain things, this seems a little bit rational.
- When you remove top cover, several small parts might fall off. One is very important – the shutter shaft. It's a small metal peg transmitting push of your forefinger to the electric contacts. Take care of it, otherwise look for somebody with good lathe. Factory tolerance is about 1/1000mm.
- Before removing rewind knob, make sure to remove back of the camera (since back cover is opened using rewind knob)
- On the winding mechanism, the advance axis, there is a tough spring – around axis inside. The winding shaft holder (141 602) should be placed on top, containing also the spring (131 617). However, make sure that one end of spring falls into small hole in that holder, so both ends of spring are fixed; otherwise advance lever won't return to start position after advancing – there will be no tension of spring. Small problem but cost me another disassembling routine. If this sounds too complicated, you will understand after fixing it again :-)
- Almost in the same place there is another IQ test. Pay attention to the disk covered with frame numbers. Under it there is ratchet wheel (131 638). It's purpose is to return frame counter back, keep it in place :-) and also set 1/60 at the start of film advancing. The latter is done by small bump keeping small lever (the one close to strap holder) in contact with shutter circuit (look for orange wire). If this contact is not adjusted just for first three frames, you will end up with 1/60 as a single and only shutter time or with metering all the time (better situation). After you assemble everything in winding and shutter mechanism, push lever signaling presence of closed camera back – it's just above release socket – slightly inside. Watch how levers operate. Now turn a little bit frame counter (like film advancing does, but you do it by hand) to frame 1. Note if lever is still in contact. It should move after first 3 frames away from metal contact, thus allowing for normal shutter operation. If not, adjust that metal piece and try again (like me, but you can save one more disassembling).
- Under ASA assembly there are three wires I had to remove. I'm not sure if it is necessary, but I removed them in order to remove front of the camera. There are two black ones and one yellow. Note the position of yellow one (it is also on page 45/fig 76 in manual – release base area). Black ones can be interchanged. I managed to mistakenly sold yellow in place of black – battery went nearly dead and shutter was working (if it was so) with a single time. Lucky, nothing more happened, I switched wires to their right places and it's working as it should.
- There is one more black wire attached to the main switch. It is not mentioned in manual, but has to be there (or I had it there)
- According to the manual used leather cannot be reused again, but I did it with relative success. Or at least, there is no sign of problems. Maybe later when I need to remove them... :-) I used flexible glue to attach it again.
- Make your own notes in the manual, like "short screw", "recessed head" etc. When disassembling, everything seems to be piece of cake, but a week later you will hardly recall that same picture.
- Be especially careful when fixing something with adhesive – if you are using fast adhesive, there is literally no way how to separate things. I made terrible mistake fixing curtain on SP drum upside down***
- Soldering LED for data back is painful task, even if you are experienced in electronics (so you do know what I mean). You have to unsolder both contacts as the last operation, both at almost the same time and removed circuit quickly. Much more difficult would be to remove old tin, you need proper device for this (Exhaust system (?). Sorry, my vocabulary is limited, but it's simple mechanical device). I decided to cut top of LEDs contacts, i.e. not to bother with LED signal since I don't use Data Back anyway.
Dealing with disassembling
I assume you have manual ready and following it, so only important steps and remarks are here:
- Remove top cover. See section about painting above, look into the manual, it's fairy easy
- Remove bottom. See the same section and also manual, if necessary
- Remove leather from front. Use the can opener on knife or bigger screwdriver to gently remove leather. It can be added again, so don't spoil this. If there is Yashica repair service around the corner, ask them about leather replacement and eventually forget my advice.
- IF there is mirror stuck or curtain stuck, you may need to disassemble winding mechanism… I don't advice it, since it is more work to do. Especially those small steal balls can be painful… use Vaseline to keep them in proper place when assembling.
- Maybe it's good idea to engage mirror lockup to keep mirror in safe. Mine was stuck at top, so I didn't make it.
- Unsolder wires, remove carefully release connector between shutter circuit and main FPC (see fig. 9)
- Ufff… remove all screws and parts as in fig. 12… there is a LOT of them.
- When removing front part, try to move it in direction of shutter speed dial (to the left). The levers contacting the mirror mechanism are somewhat stuck behind the lever next to winding mechanism (at the top) But if you carefully manipulate front part with left inclination, you should succeed.
- Removing shutter mech. assy's is relatively easy (however, here I encountered first VERY tight screw. Remember the notes about good screwdriver?). Remove mechanism carefully so you don't damage shutter curtains.
- Release the tension of curtain drums – you have to turn small black ratchet wheels clockwise or just pull out a little bit the spring keeping them.
- Remember, you probably don't have to remove curtains shafts, wheels or gears. As again, don't bother with anything not related to the subject**. All I had to do is to unscrew upper base plate screw and remove the first curtain drum – there is also some washer, you will need screwdriver or tweezers or scissors or something plus patience and perception – it will probably magically disappear among other things on table.
- Be very careful about shutter curtains.
Fixing the curtain
Well, this is the most critical part. I cleaned everything perfectly (however, don't use any mechanical removal process) and prepared drum for the first curtain.Keep in mind the position of drum! I made a mistake and fixed the drum in upside down position.***
Try to work with the glue, find some sharp stick or make it from skewer (you will have to dispose it later), anything what feels comfortable to apply only small amount of glue.
Put curtain on table, some paper below could be fine. Carefully roll the drum on the curtain a few times and get accustomed to the way it contacts with curtain.
Apply small amount of glue on curtain. Now you have a few seconds to roll drum carefully so it is in contact with glue and curtain. Wait a minute and pray for photographic God. Carefully observe the position of drum – it should be orthogonal to curtain. Roll it and unroll so you can see if this is true. Mine was finely adjusted (except that upside down position, damn) so I applied again few drops of glue to rest of drum and fix it all.
There is maybe better way how to fix the drum to curtain. For example, the process above allows (maybe) to remove end of the curtain if you spoil this job. This way you should be able to fix (a little bit shortened curtain) again, you may even left the old piece in place (just add curtain next to it). But this is my theory, fortunately I didn't need to prove it. Drawback is that you apply glue in two phases and there will remain small air bubble. I also developed very little, but visible flaw on otherwise smooth surface because of this. That way the 1/2000 time sometimes produce visible vignetting on far left part of the image – since this bump causes small slow down of first curtain at the start (remember, image on film is upside down and curtains are moving from right to left horizontally).
One important fact is the position of curtain from shutter side (right), not drums side (left). Curtain is rolled by tension on drum, but the amount of curtain fixed to the drum is not precisely specified. Precisely specified is only position of second and first curtain edge measured by specific point on body and by edges itself and speed of them.
Good example how horizontal shutter curtain is working you can find on Photo in Malaysia. Just remember that direction in RTS II is opposite to the one pictured (looking in the same direction like taking pictures).
Basically, when you advance lever, you overcome the tension of curtain drums and roll both curtains to the right. They both have silk belts which extend them – first curtain covers picture frame and extends just a little bit more to the right, covering image, rest is extended by two silk (?) belts. Second is almost completely rolled up to the right so its left edge is just on right edge of the first one. And again, second curtain is extended to the left by two belts, which are fixed to drum.
When the advance is complete, two small levers brake shafts on right and hold curtains in place. When you press shutter, the first lever releases first curtain (so it moves to the left, allowing the light to reach the film). The second lever is hold by magnet. Than, after some specified amount of time, power to the electromagnet is cut off and second lever is moved, second curtain freely moves to the left, covering again the picture frame.
For short times it is important to adjust speed of curtains so the second one is not faster than the first one (the hole between them is smaller and smaller as they are moving) or vice versa (the gap is bigger and bigger). Both situations result in an unevenly lit negative. Speed is controlled by tension on drums, there is a spring inside each one, and reachable from outside are ratchet wheels connected to axis. They are fixed in position by a spring, but you may turn them rather easily. I was very lucky, since my adjusting (about 2 turns, as specified in manual) was the right one. Otherwise, there is probably a lot of trying, since speed test of curtains requires special kind of equipment, not mentioning modified camera back, available only to service persons.
Once you assemble curtain drums, adjust position of curtain edges (i. e. you haven't red my notes carefully and disassembled adjusting plates on shaft etc.), and adjust tension of curtain drums, you may try to fire the shutter. I added advance lever, and by pushing small levers braking curtains (you really need to look into the manual, there are so many pieces of metal prohibiting me from specifying exact position, see fig. 31, part 20 and 22) you fire first and then second curtain.
As mentioned above, I turned small ratchet wheels 2 times. This proved to be nearly exact tension for springs inside the drums – or at least no visible difference appeared.
Handle everything with care, of course, pay attention to wires as you insert them into their original position.
There should be light–proof just under front cover containing circuit with metering button and self–timer. I don't know why it should be there, but I managed to create another one (the original one was melted). You may look for self-adhesive window sealing – there are some shaped types but you should find also flat one. Good pocket knife will be handy for this task.
There are some recommended steps when placing shutter mechanism into the camera body. It concerns mechanical shutter (the one coupled with DOF preview) and I strongly advice to follow both remarks in manual. If you need to use sometimes this feature (like me two days later) you may find several difficulties, mine was simply curtains not braking after advance, although I followed instructions exactly. Shot with mechanical 1/50 caused something not to return fully, like the brake lever was little bit stuck. I disassembled bottom cover and applied some Vaseline where it seemed appropriate. The space around levers is really small. Problem might also lie in using inappropriate screws for the bottom (the middle one is shorter than other two)
Rest should be easy, just follow notes in manual and read my notes above (what's not in the manual). I cannot recall anything more than such stupid problems like incorrectly soldered wires or louse screws.
Final remarks for non–active–or–non–hobbyists–at–all:
* removing screw with damaged head is of course possible, as everything, but very hard: you can use very small file to create new mortise, this time for classic screwdriver ("|" instead of "+"). But if you make it too shallow, screwdriver won't hold, if you make it too deep, you can tear away screw head. If you end up in such situation, there is basically only one way – take small drill and remove the screw. I don't suspect this will be successful in terms of tolerances required by Contax, like 1/1000mm during machining.
** I removed also adjusting plates and gear for first curtain and it took me another two hours adjusting position of them again. If you really need to remove curtain gear (fig. 24 in manual), I advice to sharpen small piece of skewer with knife to approximately the same diameter as the hole for spring pin. Try carefully to push it inside hole. The spring pin should slowly move off its position – the softness of wood is great advantage here.
*** After some philosophy thoughts about the trashcan as the main subject, I was able to modify ratchet wheel (handwork with small drill) and fix it to SP drum axis with the same good adhesive and it's working. But as I said before, I'm the lucky one.