| Author | Message | ||
     L_n_h Tinkerer Username: L_n_h Post Number: 18 Registered: 09-2007 Rating: N/A |
Good news: You dont have to figure out exactly how the mirror/release mech works! There were 2 problems at work. Firstly with the back half of the camera, the catch was indeed not hooking onto the lever C -thats why it fired upon winding. Dont know what was making it stick, but after moving it about, the mech worked well 1st time and the shutter stayed cocked when wound. Thanks for telling me where to look! The second problem was in the front plate. The shutter release button was doing nothing unless lever D was cocked (in which case it moved the tall vertical lever forward) and pressing the lightmeter button raised the mirror, and even made it close again sometimes! Sorry about my attempt to describe what was happening -but yes, at one stage I was trying to fit the front plate on with the shutter cocked (to see if that would get the shutter button involved in the operation). The cause found only after comparing the other 2 Prakticas: in the mirror area, bottom left at the front is a lever below a round pin. on this camera the lever was ABOVE the pin. This meant that the lightmeter button moved the pin (& so pushed up the shutter), when it should have left it alone. Hardly surprising the rest of the mech wouldnt work. The wrong position no doubt happened when I re-fastened down the mech with the mystery screw, as the mech was so loose it was hanging at an angle -plenty of room for the pin to get round the wrong side of the lever in the mirror chamber nextdoor. The parts have been readjusted (though the 'mystery screw' still insists on sitting in the hole crooked!) and Im reassembling the whole lot. Camera seems to work fine at the moment and next job is the awkward resoldering of the 3 circuitboard wires. (As you asked, no dismantling in the lever B or C area was done). Again Im very grateful for your help and patience on getting me this far! The counter disc is back on and associated levers in place and Ive given it one turn to tension it as you said. Noted that the disc sits at about exposure no. 22 when theres no tension on it, and obviously you have to set it manually to zero just before you put a film in. So will it automatically jump back 36 places when youve used up a film and open up the back? (Best to check now before the top is sealed again). Best wishes... |