Of course, that for the use of snowmobiles in extreme conditions to ensure the life of the village or the individual does not require any permission. In order to ride them on ice, where you can meet the inspectors of fish protection, for movement even on unpaved snowy roads, their registration with the Technical Supervisory authorities will be required.
This is a rather complicated and lengthy procedure. You will need to obtain a safety certificate, design verification calculations. The cost of the procedure itself negates the process of making snowmobiles independently in order to save money. It will not work without registration, since the engine displacement for them is usually from 150 cubes. You can’t put a smaller one, it just won’t pull the propeller. Driving a snowmobile will require obtaining a special driver’s license.
Therefore, in most cases, snowmobiles are not the best choice for an all-terrain vehicle, primarily because of bureaucratic reasons. The second reason is the increased fuel consumption, especially in deep snow and in the thaw on mild. Compared to a snowmobile with a tracked layout, snowmobiles consume 1.5-2 times more fuel for the same needs. The third is the inability to pass through the forest.
Therefore, snowmobiles, although they are a fairly simple and reliable mode of transport, are not always a good choice for those who want to have their own all-terrain vehicle, a snowmobile, especially for a fisherman who is more interested in focusing on fishing.
Traveling on ice and snow has many features. This type of transport, like snowmobile, combines a lot of advantages. However, there are also disadvantages. You can make do-it-yourself snowmobiles using the largest number of improvised materials and finished units. Moreover, they will be no worse than many industrial analogues.
If you are making any equipment yourself from scratch, you must first complete the design project. It, in turn, is divided into four stages
- Design of technical conditions, characteristics;
- Technical proposal, at the stage of which the general layout of the product;
- Sketch design, where the drawing of the product and its parts with the necessary calculations is carried out;
- A working draft in which drawings of the product are carried out taking into account current standards, already available components, mechanisms, manufacturer’s capabilities.
Naturally, the do-it-yourselfer in the workshop will not perform all the drawings in detail, and education usually does not allow it. However, you should try to make at least some sketches and calculations, especially when it comes to complex off-road equipment, such as snowmobiles.
The first parameter that should be taken into account is the traveling mass of the sleigh, G. It consists of the weight of the sleigh itself, cargo and passengers, fuel in tanks filled to capacity. This parameter is determined tentatively, it is advisable to choose it with a small margin in the initial stages. In preliminary calculations, it should be based on the fact that the weight of the sled is not more than 14 kilograms per horsepower of the engine, then it can be determined more precisely.
If you want to perform snowmobiles of a certain carrying capacity, then you can roughly take serial samples and see their camp weight. Again, it is better to take it with a margin, especially at the initial stage of design. It is always easier to recount for smaller loads than for large ones.
The second parameter is the thrust-to-weight ratio, the dynamic coefficient D. It is determined by the ratio of the traction ability to the traveling mass, D = T / G. This coefficient should not be less than 0.25, it is advisable to take it in the region of 0.3. The thrust-weight ratio will show how much the snowmobile is able to quickly move, accelerate, overcome climbs and other obstacles. Traction and travel weight are taken in kilograms.
In the previous formula, the traction ability parameter T was used. It is determined based on engine power and propeller parameters according to several formulas. The simplest is if the specific propeller thrust in kilograms per horsepower is known, T = 0.8Np. Here N is the engine power, p is the specific traction power in kilograms per horsepower.
You can determine the traction ability by another formula, which is suitable for most standard two-three-blade type screws, T = (33.25 · 0.7 · N · d) ² / 3. Here N is the rated power, d is the diameter of the screw in meters, 0.7 is a coefficient that depends on the characteristics of the screw. For ordinary screws it is 0.7, for others it may differ.
Other characteristics, such as range, speed, climb and descent, will greatly depend on the selected engine, tank capacity and dynamic coefficient. It is worth paying attention to the area of skis so that their specific pressure on snow is not more than 0.1-0.2 kg / sq.cm, and if they are designed to move on ice, perform an amphibian snowmobile, in case of ice cracks. Such a machine is also very useful in summer fishing when moving among thickets of water lilies, otherwise the propeller will wind them up and break. Such a snowmobile is used by the Ministry of Emergencies to save people from ice in the spring.
It is worth remembering that the manufacture of large snowmobiles for several people is possible only when a powerful engine is used. By itself, its use greatly increases the cost of construction, and the fuel consumption in such snowmobiles will be very large. This puts an end to a makeshift design in terms of cost savings. For example, gasoline consumption by serial snowmobiles for 5-6 people is more than 20 liters per hour, and they travel at speeds of up to 100 km / h on the ice surface, in the snow – up to 60-70.
The mobility indicators of such snowmobiles will be comparable with the cross-country ability of a snowmobile of the same carrying capacity. However, they will have less climb, less manageability, inability to walk at low speed among trees and maneuverability will be inferior to a snowmobile. If you plan to travel through the winter forest, then it is best to use a snowmobile.
Low-powered snowmobiles may well be made on their own. Many do-it-yourselfers make snowmobiles with a lifan engine, chainsaws that are designed for one and work successfully.
Good snowmobiles for fishing have a mover, which in the summer can be easily transferred to the boat, including rubber. Of course, it is advisable to use a boat with a hard bottom.
Snowmobile for fishing
Optimally, if they will:
- Have positive buoyancy
- Have a removable mover with the ability to rearrange it in the summer on a boat
If snowmobiles can be used as a full-fledged boat, then there is no need to remove the engine for the summer period .
Mostly snowmobiles are done by fishing lovers in the countryside, living near large expanses of water. It is most rational to use them in springtime on pure ice, when the snow cover on it is minimal. Here is a very good argument in favor of abandoning the classic ski structure, and on the bottom use the classic three-rib for gliders.
The stiffening ribs are reinforced so that they can serve as skates. When there is water on the ice, this will facilitate movement. At the same time, snowmobiles will go to an almost full-fledged planing mode, reducing the resistance of the environment. In summer, such a hull will be a full-fledged boat, which has high seaworthiness – overcoming small flooded braids and rapids on the river will not be such a problem for it as for a conventional motor boat.
However, to use the “Kazanka” or the old “Progress” for such things is undesirable. The fact is that their bottom has insufficient strength. And depreciation will suffer. And from hard blows the bottom will fall apart even more. The design of most modern snowmobiles and aerial boats for fishing involves the presence of a rigid bottom, which has an inflatable deck with a deck. Thus, shock absorption during movement occurs. Other designs should be considered not too suitable.
Budget snowmobile: manufacturing process
The following are typical snowmobiles with classic ski frames. They can be used for fishing, hunting and trips for one person.
The manufacture of a snowmobile frame should provide them with light weight. Usually, the lower part of the frame is made to fit the seat, rectangular or trapezoidal. It is necessary to place it a little in front of the center, as it will add another motor, tanks, screw, luggage, and it is desirable to arrange the center of gravity in the middle of the frame. The following is the manufacture of a frame for the engine, transmission and screw. It becomes triangular, the top will be the bearing on which the driving screw rotates.
The frame for the screw should be no less strong than the bottom. It must withstand serious loads, because the force driving the snowmobile is applied to it.
This frame has wide scarves in the form of rods that are attached to the uprights of the triangle and go forward. It is undesirable to take a back seat, as this will interfere with the rotation of the screw.
The frame material is selected from thick polypropylene pipes with reinforcement. These pipes give a satisfactory strength, but over time they can lose shape under load. If possible, it is advisable to use aluminum pipes and connect them with the help of trunks, tees. Joints of aluminum for welding at home are a rather complicated thing, and even in the presence of argon welding, it will lose in strength to the joint on squares.
Screw and motor
A sufficiently powerful Lifan 168f-2 four-stroke engine is used. Four-stroke engines run a little worse in the cold, but much quieter. A plastic additional gas tank from a walk-behind tractor is used. The power supply per se is quite sufficient for a snowmobile with a total camp weight of up to 500-600 kilograms.
The screw is made independently, two-bladed, has a diameter of 1.5 meters, oversized according to the drawings for aircraft models. Making a screw yourself is a rather complicated process and will require carpentry skills. In addition, you need wood from maple, hornbeam, beech, laced Karelian birch or another sufficiently strong tree, dry. If possible, it is best to purchase an aluminum screw with known characteristics in the store.
From the engine to the screw, a reduction gear is used on belts with a ratio of 1: 3 from the woodworking machine, with a tension roller. With the choice of speed modes for snowmobiles, everything is rather sad, and it’s difficult to talk about the gearbox due to the fact that the screw itself will work effectively only at sufficiently high revs, and reducing their increase in traction does not, even vice versa.
It is important! The screw must have a full guard on all sides! Most homemade snowmobiles that can be seen on YouTube or from other sources do not have it! The fence should be painted in bright color and be made mesh with a maximum step of not more than 7-8 cm.
Layout, skiing and management
The seat is located immediately in front of the engine, under it is the trunk. An additional trunk is available near the steps. The engine is controlled by the gas pedal and clutch. You can take them from an old car and connect it to the engine using cables.
There are two additional handles on the front. They are connected by cables to the front pair of skis, which can turn left, right on the vertical thrust bearing, as well as synchronously with the steering flags, which are pairwise located behind the left and right of the screw. The left handle controls the left side, the right – the right. They can be used independently, and when braking it is enough to bring the skis and flags inward by pulling both handles towards you.
The snowmobile has four skis, two front and two rear. The front two skis are short, made of alloy steel. The rear two are longer, made of plastic. Rear skis are involved in driving a snowmobile. Skis are mounted on special triangular supports, have a swinging stroke and are sprung in the front.
Painting and lighting
The snowmobile must be painted in a bright color, which will be visible from afar in the snow. It can be red, brown, blue, violet or some other similar color. It is also imperative that the propeller guard be brightly painted, preferably in a color different from the main body of the snowmobile. Usually orange is used for painting.
Of the lighting devices, it is absolutely necessary to put marker lights, as well as lights on the screw – green to the left of it in the direction of travel, and red to the right. The headlights must have sufficient power. The fact is that the daylight hours in winter are short, and usually only moving in daylight will not work.
Usually the battery lasts for 3-4 hours, this is enough to get home in the dark. If you want to protect yourself so that the headlights burn all night, if you get lost, you can recommend putting light coils from an old motorcycle.