Every film camera relies on mechanics, regardless of whether it has electronics on board or not.
For example, the shutter, mirror, aperture, or film are tensioned and transported using the force of the thumb or motors. This transmits and converts rotational force in such a way that the desired mechanical function is performed.
Mechanical components - machine elements
such as bearings, guides, gears, and parts that connect and hold the mechanics together—like screws, springs, or lock washers and others—make up a camera’s mechanics.
For DIY repairers, the mechanics are usually more accessible than the electronics, since many processes are visible and thus more easy to understand, whereas electronics remain abstract because electricity itself is invisible.
It is worthwhile to take a closer look at mechanics and build up a basic understanding of its parts and functions.
It is also helpful to use the correct technical terms
for example when writing reports, so that it is clear what is meant in each case. For instance, a spring can take different forms, and gears can appear in various configurations.
As with electronics, it is interesting to know the basics about forces and how they are applied and to be able to name them correctly.
The relevant discipline for this topic is mechanical engineering with a focus on precision mechanics. Forces and their application are covered within the scope of technical mechanics.
For beginners, literature on machine elements provides a clear introduction
Technical mechanics complements this, but is relevant for DIY repairs only insofar as it explains power transmission and motion theoretically and incorporates them into calculations.
I am not aware of any books on machine elements and precision mechanics specifically for cameras, so one must adapt general literature accordingly for this topic.
One example is
Machine Elements in Mechanical Design, 6th edition
Published by Pearson (August 1, 2021) © 2022
Robert L. Mott, University of Dayton; Edward M. Vavrek; Jyhwen Wang
For German-speaking readers
Maschinenelemente für Dummies
Anton Haberkern
But there are also many other titles.
As for technical terms in camera mechanics, the SPT Journal is the reference.
The manufacturers’ service and repair manuals also provide the designations for individual mechanical parts in cameras. However, there are inconsistencies here, and sometimes problems with the translation (Japanese → English).
What you won’t find in the literature, however
are machine elements that were designed exclusively by the manufacturer and are therefore not standardized.
For example, the clutch unit in our photo, at the top center, which belongs to a Nikon Motor Drive MD-4. Its job is to shut off the motor once the cocking cycle on the Nikon F3 is complete.
Information on this can sometimes be found in the manufacturer’s repair manual, or you may have to figure things out for yourself.
The more we, as DIY repairers, understand the inner workings of our cameras, the better our chances of success.
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A word of cautionPlease keep in mind that you’ll be using highly flammable solvents for service work, and their fumes are harmful to your health. Soldering also produces fumes that should not be inhaled. Dangerous high voltages can be present when handling electronics, especially in conjunction with electronic flash units and mains. Therefore, familiarize yourself with the safety regulations beforehand and ensure your safety. Depending on the activity, protective gear may be advisable.
All information provided without guarantee and use at your own risk.
Acknowledgments
Without the work of Master Larry Lyells, in particular, we wouldn’t have the detailed technical information we need today for service/repair of SLRs.
The SPT Journal and The Camera Craftsman, which he helped shape significantly as an author, and which contain all the necessary information and instructions are available for a fee through Learn Camera Repair.
We owe our access to them to Eugene Pate, the founder of Learn Camera Repair.
