I note right away that the author of the article cannot be responsible for your actions, and everything that you do with your lens will be done by you, and at your own peril and risk ..

Assembling the lens, as well as disassembling it, is not very difficult. The main thing is to have a tool for performing these actions.

Lens disassembly tool

  • watch flat screwdriver (I modified a small Chinese one with a dremel) for small fixing screws
  • flat, wide screwdriver for removing the aperture release lever and focus wheel.
  • a compressor or a can of compressed air to remove dust that has settled on the mechanisms during the time the lens was disassembled.
  • gasoline "Kalosha" from stores like "Radio amateur" for cleaning petals and removing old grease
  • rags (fully disposable wet wipes are suitable, but if there are lint-free, then this is even better)
  • Litol grease (most common), or better.
  • neatness and attentiveness.

The procedure for assembling Tair-3C

If you need disassembly instructions, you must read this material from the end.

This instance lens Tair-3FS, a malfunction of the diaphragm itself occurred (the petals corroded and stuck together, due to the formation of condensation inside lens). The petals were soaked in gasoline and cleaned and dried. Then the assembly was carried out lens.

m42 tair 3fs 300mm f4.5 maintenance 1

  • The diaphragm blades are set in place in a clockwise direction, stacking them on top of each other, until diaphragm will not take its usual form for us.
  • There is a recess for each petal on the body
  • Then the upper fixing ring is put on all this, into the grooves of which we bring out the attachments of the petals sticking up.

m42 tair 3fs 300mm f4.5 maintenance 2

The petal fasteners must be inserted into the grooves (use a bent toothpick or any other object convenient for you). The first ring, on which we placed the petals, is fixed with a screw in a groove that is mirrored relative to a similar screw that sets the selected aperture value.

  • Installing the assembled diaphragm into the body lens Tair-3FS, and center it according to the marks applied before disassembly. We fix it.
  • Then we insert the spacer rings inside. Thin at first, then thicker.
  • We screw in the threaded ring and fix it.

m42 tair 3fs 300mm f4.5 maintenance 4

When diaphragm assembled correctly - the center has the shape of a circle.

  • The ring is installed and secured with a screw.
  • We blow out the insides with compressed air.
  • Reinstall the front glue.
  • Screw in and fix with screws.
  • At the same time, we check if all the other screws are in place.

m42 tair 3fs 300mm f4.5 maintenance 15

  • We remove our handprints with the same gasoline in which the diaphragm blades were soaked.
  • We install the diaphragm cocking in its place and screw the threaded locking ring over it, fixing it with a screw. The diaphragm control screw must be inserted into the groove of the cocking mechanism.

m42 tair 3fs 300mm f4.5 maintenance 18

  • Now we need to tighten the cocking mechanism springs. At this stage, by the way, you can adjust the tension of the springs. Useful when the springs are stretched or you want to increase the speed of the diaphragm. I trimmed all three springs slightly at both ends, roughly as in the photo below.

It turned out to be harsh. Birds can shy away from knocking when the trigger is pulled, but now diaphragm closes very quickly. Optimal, I think, is shortening by 2 turns on each side (just those that are bent)

  • The springs are attached at one end to the projections on the lens body, passed under the cocking mechanism body and brought out into the groove, being attached to the projections on the body.

m42 tair 3fs 300mm f4.5 maintenance 20


  • We fix the cocked diaphragm lock - it should look towards our springs with a beveled end. We fasten it with 4 screws.
  • We screw the outer ring, with the inscription "Tair" and "Made in the USSR", up to the mark we applied before disassembly. We fix it with a screw. Left a little. The combination of the two parts of the case is coming.

m42 tair 3fs 300mm f4.5 maintenance 26

  • Sometimes the body mount at the base is developed, and the lens starts to scroll around its axis when we try to remove it from the camera. To prevent this, it is necessary to stretch the fastening screws.

m42 tair 3fs 300mm f4.5 maintenance 27

  • Before joining both body parts lens it is necessary to set the value of the switch on the outer part of the case to "22", since we assembled the diaphragm in the "closed" state. The cocking lever is set to f / 4,5.
  • We connect both parts of Tair, insert one into the other. If you cannot fully insert it, you need to unscrew the plastic screw cap (connected to the focusing wheel), and carefully screw the lens counterclockwise until the plastic stop of the repeater contacts the cocking lever. Then we align the lens and place the trigger plate on the body.
  • Trying to cock the diaphragm. If collected correctly, then diaphragm will be locked at the set value and descent will occur as usual. It remains for us to return the focusing wheel to its place, having previously set it to infinity. If you removed the threaded strip from the body, then it must also be returned to its place.

m42 tair 3fs 300mm f4.5 maintenance 30

Thus, we put back Tair-3FS. To disassemble it, you just need to go through the pictures in reverse order, and be a little careful when disassembling, since not all the places in which the screws for fastening the inner rings and the diaphragm are located are shown in the photo.

Adapters for cameras and lenses

Sometimes I buy photographic equipment from the USSR and not only. You can offer your write me. Help the project: 5469 1200 1062 4624. Comments can be left without registration and SMS

Add a comment

Your email address will not be published.