Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
10-16-2008, 04:33 AM   #1
Junior Member




Join Date: Sep 2008
Location: South of France
Posts: 37
MZ5n mirror blocked, service manual?

Hello evry body
i just bought a MZ5n but after that i put the battery and shoot, the mirror stayed blocked up.
Do you know what can i do, or do you know where i can find a repair service manual?
Thanks

10-16-2008, 10:35 AM   #2
Junior Member




Join Date: Sep 2008
Location: South of France
Posts: 37
Original Poster
does anyone can help me ?
10-16-2008, 12:20 PM   #3
Veteran Member
AndrewG NY's Avatar

Join Date: Dec 2006
Location: Chappaqua, NY
Photos: Gallery
Posts: 679
Return it to the seller?

Is the mirror stuck up due to deteriorating mirror foam? You may be able to *gently* move it down.

I have my own broken 5n which I haven't dealt with yet. The symptoms sound somewhat different than yours but it may be related. My understanding is that the mirror motor gear was originally plastic and tends to strip. The replacement part is metal. I haven't done this yet so don't know just how easy it is for a layperson to replace the part. My guess is - not-that-simple, but I may give it a go anyway at some point.

Good luck. If you figure out what happened you may want to post for posterity.
10-16-2008, 09:58 PM   #4
Veteran Member
wlachan's Avatar

Join Date: Sep 2006
Location: Canada
Photos: Albums
Posts: 2,626
The plastic gear on the mirror motor has cracked. To replace that motor, the whole camera has to be disassembled. Assuming you are skillful to disassemble and assemble everything, soldering the flash circuit will be the most risky as a careless short can kill the camera beyond repair. I have the parts manual for the MZ-5, if you are interested, just email me. Good luck.

Old & new mirror motor





Last edited by wlachan; 10-21-2010 at 07:07 PM.
10-16-2008, 10:06 PM   #5
Junior Member




Join Date: Sep 2008
Location: South of France
Posts: 37
Original Poster
Hi AndrewG and Wlachan
Thanks for your reply. I will test to repair it and i will take pictures for each step of dissassembly (for the science ) ).
Wlachan i send you an pm for the file.
Thanks you again
11-19-2008, 03:20 AM   #6
Veteran Member
titrisol's Avatar

Join Date: Dec 2007
Location: In the most populated state... state of denial
Photos: Gallery | Albums
Posts: 1,098
Crap! I had the same symptons last night
I received the AA battery pack, put it on, and after 3 shots the mirror got blocked, the lens did not return to fully open and the film advanced like nuts

Another camera bites the dust!
02-21-2009, 09:23 AM   #7
New Member




Join Date: Feb 2009
Location: France
Posts: 17
Hello,

I have exactly the same symptoms after having tried my MZ-50 that was sleeping from years.
Batteries are OK (I tested with new ones).
I started disassembling the bottom, I saw the white and green gears that drive the mirror ans shutter. I moved them slowly with a screwdriver, and I feel a hard point at each turn of the motor, that has got a plastic gear.

So, same conclusion.
Wlachan, if you don't mind, I would be really interested in having the service manual to try to reach the motor and replace it.

In advance, I thank you very much for your help.

Bob
05-02-2009, 09:14 AM   #8
New Member




Join Date: Feb 2009
Location: France
Posts: 17
(2 months later)

Hi Alan.
I changed the motor for 20$, following your instructions.
The shutter mechanism is correctly rebuilt and set (after a desintegration error from my part).

Unbelievable, I remounted the whole camera without an error.
It works now , I'm still surprised to have done it at the first shot...

Before loading a new film, I tested the shutter speeds on my 3$ testbench, (2 lasers from toyguns + phototransistors + 1 battery + 1 switch + 1 microphone wire + jack + PC + Audacity).
Seems to be good.

Of course the last test will be done with the results with the film, I cross fingers.

Alan, let me say you that I appreciated a lot the help you gave me, and to be so patient with me.
I learnt a lot about photograph engineering (especially on shutter), and to be calm too, thanks to you.


Regards,
Bob

05-03-2009, 05:20 AM   #9
New Member




Join Date: Feb 2009
Location: France
Posts: 17
Those are some pictures of my MZ50 submitted to the testbench :
- the test bench with Audacity program (Stereo mode to measure travelling time along 22 millimeters between the 2 spots)
- the camera with closed shutter
- the camera with opened shutter.
Attached Images
View Picture EXIF
DSC-W1  Photo 
View Picture EXIF
DSC-W1  Photo 
View Picture EXIF
DSC-W1  Photo 
View Picture EXIF
DSC-W1  Photo 
05-03-2009, 05:24 AM   #10
New Member




Join Date: Feb 2009
Location: France
Posts: 17
[I think I had a problem when posting my previous reply (2 months after ther first one), that's why I post it again, in relationship with the testbench that helped me to validate the shutter mechanism, and the whole camera after final rebuilding.]

Hi Alan.

I DID IT !

Unbelievable, but after changing the motor, I remounted the whole camera without an error, thanks to your guidance.
It works, I'm still amazed to have done it at the first shot...
The shutter + mirror mechanisms resynchronized themselves when putting batteries inside.
Before loading a new film, I tested the shutter speeds on my 3$ testbench, as shown on attached pictures (2 lasers from toyguns + phototransistors + 1 battery + 1 switch + 1 microphone wire + jack + PC + Audacity).
Seems to be good.

Of course the last test will be done with the results with the film, I cross fingers.

Alan, let me say you that I appreciated a lot the help you gave me, and to be so patient with me.
I learnt a lot about photograph engineering (especially on shutter), and to be calm too, thanks to you.

Bob

PD : I needed to retest shutter speed because I made a mess dismantling accidentally the shutter mechanism box - a nightmare and a genious mechanism at the same time - ; thanks to Alan and of some litterature on internet I finally understood how shutter works, and built a cheap tesbench to calibrate curtains springs for the expected speeds.
If anybody needs help on it, he's welcome to ask me help on that topic.

Last edited by Bob Bimon; 05-03-2009 at 05:30 AM.
05-14-2009, 05:22 AM   #11
Site Supporter
Sluggo's Avatar

Join Date: Sep 2006
Location: Ames, Iowa
Photos: Gallery | Albums
Posts: 603
I DID IT TOO! Thanks to Bob for taking lots of pictures, writing down what he did, and sharing all of that with me. Mine is a ZX-M, which has some differences, but they were similar enough that I could figure out what to do.

Nice little camera, especially with the FG grip (now on $10 clearance from freestylephoto.biz, by the way).
05-20-2009, 02:37 PM   #12
New Member




Join Date: Feb 2009
Location: France
Posts: 17
Thanks Sluggo, you're welcome !

For anybody that would need to repair his MZ-5x or ZX-5x, here you have the procedure I wrote for CGJung and Sluggo.

Good luck, and enjoy !

Attached Files
File Type: zip MEZ50 repair procedure issue3.zip (1.39 MB, 3278 views)
06-09-2009, 02:50 PM   #13
New Member




Join Date: Feb 2009
Location: France
Posts: 17
Well Well Well...

Hum, I just received my pictures from the test roll.
All pictures in exterior and sunlight and allright, including high speeds as 1/1000 and 1/2000.
But.... a big problem with Sync flash, as you can see below

This is the dark band problem, explained by a too slow curtain.
What I understand with this camera, is that :
- sync flash speed is 1/100
- dark band is due to 1rst curtain opening from bottom to top, the negative roll being of course inverted (upside-down).
- so dark band below is in fact due to lack of flash light (1/1000) during the uncomplete travel of 1rst curtain (still shadowing the top-level negative at mid-course).
- I checked curtain speed again from my testbench : about 10ms, that is is 1/100.
- The problem is that I have no idea of the time when flash lights : it's supposed at the end of 1rst curtain travelling, i.e. 10ms after start. If there is some dead time (needed to take acceleration from zero), this is NOT enough speed to be in time !
The dark band at 50% of height means that I need to recover...5ms in travel time !

So : I suppose I need to dismount again part of the camera to have access to those 2 spring set gears of the shutter, and add some turns (I had set to 1.4 turn to have about 11ms; at 2 turns preset I had found 8ms).
But I don't know how many turns are necessary at least...


If you have somme suggestions...
Attached Images
 
06-11-2009, 02:24 PM   #14
New Member




Join Date: Feb 2009
Location: France
Posts: 17
I checked the curtain travel with the camera body without lens, in flash mode, and backdoor opened (I pushed the door switch to simulat the closed state).

No way : I clearly see the upper part of the curtain masking the aperture at the flash triggering.

No enough fast.
I calculate I need to add about +50% torque on curtains springs.

OK, I'll do it sooner or later, when camera will be disassembled again
07-02-2009, 02:55 PM   #15
New Member




Join Date: Feb 2009
Location: France
Posts: 17
OK, done...
It was hard to set the springs again : I finally had to set it from 1.5 to 3 turns for each spring to reach a total 10ms travel (including acceleration phase).

The problem is that, at the last dismount/remount operation, the flashboard suffered something like a short (I forgot to discharge capacitors, Gosh ! ) and doesn't work any more. So I disconnected the flashboard from circuitry.
So, it's all right with daylight. Flash mode is now over, except if I use an external flash.

Anyway, I'm not very fan of flash photographs, so I don't mind any more about the flash
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
bit, body, brass, change, eric hendrickson, gears, mirror, mm, mz5n, plastic, repair, service, wonder, zx-m
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Looking for service manual: MZ-5n and MZ-50 CGJung Pentax Film SLR Discussion 24 04-20-2011 12:01 PM
ME Super Service Manual pandarocket Pentax Film SLR Discussion 20 03-17-2010 12:32 PM
K100D Service Manual? Spag Pentax DSLR Discussion 4 12-12-2009 04:17 PM
Need service manual for a PZ-1p. Bob 256 Pentax Film SLR Discussion 6 07-17-2008 07:47 AM
MZ-S Service Manual?! time-snaps Pentax Film SLR Discussion 1 02-14-2008 05:25 PM



All times are GMT -7. The time now is 01:38 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top