The Drum at Work

Screw-drum potato digger on a self-propelled chassis

We named our potato digger a screw-drum digger after its two main working elements. It is intended for harvesting tubers on educational and experimental plots, as well as household plots and gardens. That is why an electric motor is used as the drive, although of course an internal combustion engine of suitable power can also Read more…

Flower Bed — A ‘Construction Set’

DIY modular wooden mobile flower bed design

No matter how popular flower beds are among flower-growing enthusiasts, they usually differ little from ordinary garden beds. And this impression is not saved by attempts to refine them with all sorts of brick borders, fences made from random pipes, or, worse still, car tire covers. Besides, such flower beds have a permanent “registration”: they Read more…

An ‘Electromine’ for Rats

DIY capacitor electromine vs rats: circuit guide

Many people keep various pets, and spending time with them brings plenty of pleasant moments to both children and adults. However, there are also animals that constantly live near humans and often visit their homes (for example, mice and rats). Yet they are uninvited and even harmful guests, since they are considered (and, probably, not Read more…

Manual Concrete Mixer

DIY hand concrete mixer for cement mortar mixing

Prepared cement mortar needs constant mixing, otherwise it hardens quickly. But that is easier said than done; doing this work by hand is extremely tiring — it is hard to lift a shovel full of mortar. How can one try to use one’s strength more efficiently? That is how this labor-saving device appeared in my Read more…

Tandem — A Bicycle for Two

Homemade tandem bicycle: frame and drive

For many years I have been a regular subscriber to “M-K” and find in it a great deal that is interesting and useful. I hope my experience will also be of use to other readers: I want to share my thoughts and practical recommendations on making and operating a tandem bicycle. I built such a Read more…

Autogyro Rotor

Autogyro rotor blades: manufacture, balance, hub assembly

It is no exaggeration to say that the most important part of a glider-autogyro is the rotor. The autogyro’s flight qualities depend on the correctness of its airfoil, on mass, centering accuracy, and strength. True, the unpowered craft on a car tow rises only to 20–30 m. But even flight at such a height requires Read more…

A Sauna for Bees

Thermal unit for treating bees against mites

For almost twenty years, a design club for agricultural modeling has been operating at the Chernihiv regional Station of Young Technicians. Over the years, the students, under the guidance of their mentors, have developed and built many useful machines, mechanisms, and devices, many of which are of practical economic importance and bring real benefit to Read more…

Electric Cycle

DIY electric motorcycle: design, wiring, and road tests

Ecology and environmental protection are becoming increasingly relevant topics worldwide. Requirements for harmful emissions from vehicles are constantly being tightened. That is why major manufacturers are developing and starting to produce electric and hybrid cars. These trends are also reaching our country. And while the evolutionary direction of automotive development has been defined and is Read more…