pb908
Well-known
Impossible...!!!!
I got some questions from people who read my previous thread regarding my Titanium Shutter Leica IIIC :
http://www.rangefinderforum.com/forums/showthread.php?t=105382
they asked me if it is possible to replace titanium shutter on Leica M body. I didn't know the answer that time as I don't have any M body for CLA. (I had just received a nice M2 off ebay, but that was just being cla-ed).
later, a friend asked me to CLA his broken M3, actually it has lot of problem as well as broken curtain, and he sent it along with an old Nikon F to be junked for this project. what a nice weekend project then.
after opening the shell and top cover of M3, I start to remove old curtains from M3 and clean all the mechanism. replacing curtains should be easy as I have done it several time. then I install the titanium curtains there.
the good news is :
Nikon F Titanium Shutter is EXACT size as the one on Leica M !!!
but then, after few trials, I got stuck, I try another approach, and again stuck. I'll let you know the facts and the problem :
1. Titanium shutter is so thin (and STRONG), imagine your curtain is just as thin as alumunium foil or a thin sheet of plastic.
2. the original leica curtain is somehow thick enough, made from silk and rubber.
3. leica have many tight tolerance regarding this curtains replacement.
The problem is this different curtain thickness makes the titanium shutter entering the aperture window to fast compare to the normal curtains.
assume, if I set all mechanism to the unwinded condition, and put my 2nd curtain end to the most right area blocking the film aperture (camera facing me) and glue it at this position.
when I wind the shutter, all curtain move to the left and winded properly, but when I set shutter to 1s, and press the shutter, this will happen :
1. 1st curtain move to the right, no issue.
2. the slow speed escapement will hold 2nd curtain for 1second (and at the same time, the 2nd curtain move slowly due to the latching cam almost disengages). In normal leica curtain, this movement is still not entering the film aperture, but with Titanium shutter, the curtain move and ENTERING the film aperture window !!!
3. when the timer is complete, the cam release 2nd curtain and the curtain move to the right, no issue.
point no2 above, happen due to the thickness difference. when i wind normal leica shutter, the winding become bigger and bigger, this increase the diameter of the winding, and as well the length of the curtain being winded. that's why, in leica curtains, this have no problem, but with titanium curtain, due to the thin material, the winding diameter is not increased as it supposed to be, so if I compare both, with the same winding mechanism applied, the leica curtain will have more length compare to the titanium one.
in my example, I set the 2nd curtain to the most right and glued it in this position, the result is during the slow speed escapement work, the 2nd curtain enter the film aperture.
if I set the 2nd curtain in the most left (winded position + have enough space for the slow speed escapement to work before entering the film aperture), and glued from there, the problem will become on the right side which 2nd curtain is not close completely (due to lesser distance it produce from the thin winding).
several of my option (some tested, some doesn't) :
1. adding some layer of tapes in the drum. this work to fix the curtains movement, but then the drum become bigger and can't be covered by the housing cover => not a solution
2. set the brake to brake later (for the curtain to travel longer) => not a solution, I disassembled and set it to the maximum distance, still doesn't enough.
3. thicken the 2nd titanium curtain (maybe by gluing curtain silk in one side of it), but to get the same thickness will be a problem.
I have test by adding few layer of thin tape to the 2nd curtain and it did work as it should be, at least the theory is working.
4. use normal silk/rubber for 2nd curtain, only one titanium curtain in 1st curtain. not a real titanium leica then
5. all curtain use normal silk/rubber curtains
then this become normal leica 🙁
any idea ?
I got some questions from people who read my previous thread regarding my Titanium Shutter Leica IIIC :
http://www.rangefinderforum.com/forums/showthread.php?t=105382
they asked me if it is possible to replace titanium shutter on Leica M body. I didn't know the answer that time as I don't have any M body for CLA. (I had just received a nice M2 off ebay, but that was just being cla-ed).
later, a friend asked me to CLA his broken M3, actually it has lot of problem as well as broken curtain, and he sent it along with an old Nikon F to be junked for this project. what a nice weekend project then.
after opening the shell and top cover of M3, I start to remove old curtains from M3 and clean all the mechanism. replacing curtains should be easy as I have done it several time. then I install the titanium curtains there.
the good news is :
Nikon F Titanium Shutter is EXACT size as the one on Leica M !!!
but then, after few trials, I got stuck, I try another approach, and again stuck. I'll let you know the facts and the problem :
1. Titanium shutter is so thin (and STRONG), imagine your curtain is just as thin as alumunium foil or a thin sheet of plastic.
2. the original leica curtain is somehow thick enough, made from silk and rubber.
3. leica have many tight tolerance regarding this curtains replacement.
The problem is this different curtain thickness makes the titanium shutter entering the aperture window to fast compare to the normal curtains.
assume, if I set all mechanism to the unwinded condition, and put my 2nd curtain end to the most right area blocking the film aperture (camera facing me) and glue it at this position.
when I wind the shutter, all curtain move to the left and winded properly, but when I set shutter to 1s, and press the shutter, this will happen :
1. 1st curtain move to the right, no issue.
2. the slow speed escapement will hold 2nd curtain for 1second (and at the same time, the 2nd curtain move slowly due to the latching cam almost disengages). In normal leica curtain, this movement is still not entering the film aperture, but with Titanium shutter, the curtain move and ENTERING the film aperture window !!!
3. when the timer is complete, the cam release 2nd curtain and the curtain move to the right, no issue.
point no2 above, happen due to the thickness difference. when i wind normal leica shutter, the winding become bigger and bigger, this increase the diameter of the winding, and as well the length of the curtain being winded. that's why, in leica curtains, this have no problem, but with titanium curtain, due to the thin material, the winding diameter is not increased as it supposed to be, so if I compare both, with the same winding mechanism applied, the leica curtain will have more length compare to the titanium one.
in my example, I set the 2nd curtain to the most right and glued it in this position, the result is during the slow speed escapement work, the 2nd curtain enter the film aperture.
if I set the 2nd curtain in the most left (winded position + have enough space for the slow speed escapement to work before entering the film aperture), and glued from there, the problem will become on the right side which 2nd curtain is not close completely (due to lesser distance it produce from the thin winding).
several of my option (some tested, some doesn't) :
1. adding some layer of tapes in the drum. this work to fix the curtains movement, but then the drum become bigger and can't be covered by the housing cover => not a solution
2. set the brake to brake later (for the curtain to travel longer) => not a solution, I disassembled and set it to the maximum distance, still doesn't enough.
3. thicken the 2nd titanium curtain (maybe by gluing curtain silk in one side of it), but to get the same thickness will be a problem.
I have test by adding few layer of thin tape to the 2nd curtain and it did work as it should be, at least the theory is working.
4. use normal silk/rubber for 2nd curtain, only one titanium curtain in 1st curtain. not a real titanium leica then
5. all curtain use normal silk/rubber curtains
then this become normal leica 🙁
any idea ?
