Almost all bicycle drive designs share a common drawback that reduces their efficiency. This drawback is the uneconomical expenditure of muscular energy when shifting effort from one leg to the other as the pedals pass through the “dead points” (vertical position of the cranks). Most of the muscular effort at that moment is directed toward Read more…
The kart design (Fig. 1) has no complex units requiring high qualifications of performers and can be replicated in technical clubs of schools or at young technicians’ stations that have a lathe and gas welding. The kart construction must be carried out in a certain sequence. First, the front and rear axles are manufactured, and Read more…
Once upon a time, there was a popular TV show “You Can Do It” where craftsmen talked about the designs they had created. Perhaps it was there that information about air-cushion vehicles first appeared. And publications in the “Modelist-Konstruktor” magazine pushed many enthusiasts, including ours from Angarsk (mainly amateur fishermen), to build such machines with Read more…
The watercraft we would like to introduce to readers can quite rightly be classed as a small vessel. After all, what else would you call a pair of versatile self-propelled floats that can easily be used both as water skis and as a two-seater pleasure catamaran. As can be seen from the drawings, each float Read more…
This two-cylinder engine, designated DD-700/40, was designed and built by Georgy Dorfman, head of the public design bureau “Aerosam”. The motor turned out to be exceptionally successful: reliable, relatively simple, and quite lightweight. The motor was exhibited at the IV All-Union Review-Competition SLA-87 and was approved by the technical commission of the rally. To date, Read more…
In gardens and vegetable plots, at dachas and school grounds — everywhere where there is a need to cultivate small areas of land, universal walk-behind tractors (UWT) are widely used. Including homemade ones, often created with maximum use of standard units and parts. One such design was developed and successfully tested by young technicians at Read more…
For tourists and skiers in “large” mountains with complex terrain and significant elevation differences, chairlifts are usually installed. On their traction-carrying cable, they have special suspensions with one or two chairs. The length of such lifts is limited to 1.5—2 km: experience has shown that an ascent exceeding 10—15 minutes in time can lead to Read more…
Last spring I built myself water skis. But I rarely got to ski on them, since the tow was provided by… a motorcycle with a sidecar. Building a dedicated boat would have meant considerable expense, powerful engines, and above all—time. So I thought: why not design one large ski, fit it with an engine and Read more…
Among the large family of “Lebed” (Swan) designs by Vitaly Konstantinovich Savitsky, the “Lebed-7” stands out for its bold layout of components and assemblies, successful centering, good streamlining, and smooth ride. The sled (see figure) is a four-ski design with steerable front skis. The steering is automotive-type, with a worm gear and steering linkage. The Read more…
«After the publication in issue 12 of 1971 of the magazine «Modelist-Konstruktor» of the article «Meet the Tulpar» we received many letters from readers asking to send drawings and descriptions of various components of the Tulpar electromotor scooter. Since we cannot send drawings to each reader individually, we ask you to print them in the Read more…
