Open the housing of a Minox

Minox A housing: 1 cap (top part), 2 bottom part, 3 front cover, 4 control panel

Opening an 8×11 Minox can be a nightmare if you don’t know exactly what you’re doing. It is very easy to irreparably damage sensitive parts such as the shutter blades or make it impossible to assemble the camera. There is also the risk of accidentally changing settings or damaging the complicated internal mechanism.

In order to service or repair the camera, various housing parts must be removed. It took me a lot of research, time and Minox cameras to learn how to do it. Since it’s not obvious how to open an 8×11 Minox and there’s a lot you can do wrong, I wrote a comprehensive guide here to make it easier for you.

Remove the cap

Difficulty level

Simple

Risks

Scratching the cover if you slip with the screwdriver.

For what reason?

  • Required for later opening of the control panel.
  • Can be used to remove resin from the escapement if you don’t have to remove the control panel anyway. However, the control panel must always be removed to oil the escapement bearings.

How?

  1. Open the film compartment and pull it all the way open.
  2. Loosen the 2 screws on the head side. Since space is limited in length, use a screwdriver bit. A short bit adapter can help apply more torque.
    Open the minox cap with a screw driver
  3. Remove cap. The cap can now simply be pulled back.
    View on the escapement with the cap removed

Hints

  • The screw heads are sealed with a black lacquer that you have to scrape out of the slot with a scriber.
  • Since there isn’t enough space for a screwdriver, use a screwdriver bit. If a screw is too tight, you can turn the bit with pliers or use a bit adapter as shown in the photo above.

Remove the bottom part

Difficulty level

Medium

Risks

Overstretching of the blade springs.
Scratching the film chamber when loosening the starhead screw.

For what reason?

• To remove the front cover
• To remove the control panel
• To remove the back

Note: It is not necessary to remove the cap first.

How?

Dismantling

  1. Be sure to press the trigger first so that the shutter blades are free.
    This means that the shutter blades are released from the locking pins and can move freely with the lower part in the blade guide. If the shutter is cocked, pulling the lower part would put unnecessary strain on the blade tension springs.
  2. Open the film compartment
  3. Unscrew the locking screw above the starhead screw a few turns
    Housing with starhead screw (1) an locking screw (2)

    Homemade screwdriver for starhead screw
    Loosened starhead screw
  4. Turn the starhead screw until it protrudes at least 2 turns. A special key is recommended for this purpose. It can be made from a scalpel by contour grinding. The screw has 3 slots so that you can reach the next slot after turning it 60°. Use the key to turn the screw until you reach the next slot and so on.
  5. Turn the camera over and carefully pull off the lower part until the slot between the lower part and the control panel is approx. 3 to 4 mm large.
    Spring hooking arm in housing
  6. Through the slit you can now see part of the toothed copper spring hooking arm on the left.
  7. Insert a thin screwdriver along the spring hooking arm as far as possible towards the lower end of the housing. Then carefully use the tip of the screwdriver to lever the spring hooking arm downwards by approx. 1 mm until you hear a quiet click.
    The following two pictures show a look inside the housing for a better understanding. However, this cannot yet be seen in this step.
    Fastening of spring hooking arm in housing

    Attachment point for spring hooking arm in bottom part
  8. Now the spring hooking arm is detached from the lower part and you can completely remove the lower part without the spring hooking arm moving.
    If the spring hooking arm moves, it is still connected to the lower part. Then stop pulling immediately and first loosen the connection as described above.
    Attention: The spring hooking arm can be completely pulled out with the housing’s lower part. However, the highly sensitive shutter blades are then completely removed from their guide. They then hang freely on the spring hooking arm and can easily be damaged. It is therefore better to detach the spring hooking arm from the lower housing part beforehand.

Reassembly of the lower housing part

  1. Back and front cover must be assembled first.
  2. At the same time, push in the spring hooking arm and insert the blades into the blade guide. The best way to do this is to clamp the camera vertically in a vice so that you have both hands free.
  3. Place the lower housing part on the guide rails and push it all the way on so that the spring hooking arm engages in the lower part.
  4. Don’t forget to tighten the locking screw otherwise the protruding screw will hit the lower part when the camera is pushed together.
  5. Screw the starhead screw back in.
    Check: The lower part must not be able to be pulled out further than is necessary for tensioning (otherwise screw the starhed screw in further) and it must be easy to move (otherwise loosen the starhead screw slightly)

Remove front cover

The front cover is held in place by a screw on the left below the viewfinder. Loosen the screw and pull the cover downwards.
Note: Be careful not to lose the tiny screw.
The filter unit is loosely attached to the slider under the front cover. The driver ensures that every time the camera is pushed together, the filter is pushed away from the lens.

Front cover: 1 lens cover, 2 viewfinder, 3 yellow/green filter, 4 filter slider, 5 driver for filter reset

Now you have access to the viewfinder, the filter unit and the blade guide:

Minox front without cover

Remove the control panel

Difficulty level

Difficult

Risks

The distance dial and image counter disc can fall out, which may require complex readjustment of the lens and the film feeding mechanism.

For what reason?

  • Remove resin and oil of the escapement mechanism
  • Grease the spring hooking arm
  • Grease the guide surfaces on the housing to pull the camera apart
  • Set the coupling between distance dial and lens
  • Set the image counter
  • Set negative distance

How?

Dismantling

  1. The cap must be removed first.
  2. Set the shutter speed to ½ s because this time is set automatically when the control panel is removed. Otherwise the shutter speed dial will be positioned incorrectly when it is mounted later.
  3. Set the distance to infinity as a precaution in case the distance dial falls out.
  4. Loosen the screw on the upper part of the control panel.
    Minox control panel locking screw
  5. Now comes the hardest part.
    Lift control panel
    After loosening the screws you are ready to lift the control panel at the top. At the bottom of the control panel there is a tab that reaches into the camera body and secures it from being lifted. Now fix the distance dial with one finger and lift the upper end of the control panel with your other hand. As soon as the control panel is far enough above the distance dial, carefully push the control panel backwards until it slides out of the tab and remove it. The distance dial must be kept in place at all times!

Caution: When the control panel is removed, the distance dial and the image counter disc can slip and fall out of the housing when moving the spring hooking arm. Inserting and adjusting this unit is complex, so always press with one finger when operating the spring hooking arm to cock the shutter.

Reassembly

  1. Push the spring hooking arm all the way in.
  2. Position the image counter disk correctly. Check with the control panel in place, see chapter Image Counter.
  3. Set the shutter speed to ½ s.
  4. Slide on the control panel at the bottom tab, leaving enough space at the top to avoid touching the distance dial.
  5. Adjust the distance dial with tweezers until the control panel can slide over it.
  6. Carefully press the control panel down over the distance dial and adjust both correctly.
  7. Press the control panel down.
  8. Screw in both screws

Remove the back cover

Difficulty level

Simple

Risks

  • Viewfinder can be spotted
  • Pressure plate can be damaged

For what reason?

  • Adjust distance setting, set lens to infinity
  • Clean the pressure plate
  • Clean viewfinder
  • Adjust the pressure plate
  • Measure shutter speeds with conventional method
    Read here my reflective Minox specific method without dismantling the camera

Preconditions

  • Bottom part is removed
  • Controlpanel is removed

How?

Dismantling

Back cover
  1. Loosen the two screws.
  2. Remove cover.
    Back without cover
  3. Remove pressure plate.
    Back without pressure plate
  4. Remove the viewfinder glass cover.

Reassembly

Reassembly is done in reverse order.

Back to Minox repair

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