Homemade snowmobile for a fisherman. Homemade snowmobiles with a low-power engine (drawings) DIY snowmobile manufacturing
Self-made snowmobiles are not able to overcome terrain with steep slopes. This is their design feature. The thing is that the propeller acts as the propeller of the installation, sometimes it is also called a propeller. If you decide to make your own snowmobile, you can use a system of three skis. Some craftsmen use 4 skis, and a supporting body can also be used during work. The last type of snowmobile involves the possibility of moving the structure not only on snow, but also on water.
Homemade snowmobiles can have all kinds of designs. The system can be single, then you have to use three skis. In the manufacture, a hull beam will be used, as well as a transverse beam designed for mounting rear skis. Among other things, you will need to use a sub-frame. A set of bars used in the work must have a cross section of 35x40 mm. The fixation of the elements will be carried out on M6 bolts. In the place of the docking nodes, it will be necessary to mount steel corners, as well as washers of a significant diameter, they will play the role of a retainer that will prevent the wood from deforming.
Component structures
Home-made snowmobiles in the area of \u200b\u200bmounting the turntable in front of the located ski suggest the presence of a steel plate, brackets, and also squares. Skis must be made of wood. The front area of the body is closed by an element that will act as a hood. Steel brackets are located on its sidewalls. A bicycle headlight will be mounted on top of the hood. The driver's seat can be made of plywood, you need to take a canvas, the thickness of which is 8 mm. The front of this element will rest on two springs borrowed from a bicycle saddle. The cross bars on which the motor is mounted have different lengths. The rear bar will be long, it is fastened with tubular struts and plays the role of a propeller guard. At its ends, it is necessary to fix plates curved along the radius of the propeller. The latter in the process of work will need to be painted red. The rear skis have boar brackets. They can be made from strip steel, from which a blank with a size of 5x30 mm is pre-cut.
Homemade snowmobiles will include, as already mentioned, boar brackets, with the help of which skis are mounted on M10 bolts to the corners. The latter are mated with the bars of the transverse beam.
Features of ski manufacturing
Skis are assembled using casein glue. First you need to prepare three plates made of plywood. You need to use plywood 4 mm thick. Along the edges of the ski, you need to strengthen it with shaped oak boards. The soles of the skis at the bottom must be reinforced with sheet steel. Among other things, they need to be provided with transverse undercuts. In order for the skis not to crash into the snow when hovering, retard cables with springs must be mounted on them.
motor part
Homemade snowmobiles control the turn of the front ski. From the steering column is a cable transmission. To control the motor, the structure will have to be equipped with gas levers, in addition, ignition timing will be needed. Wiring can be borrowed from a motorcycle. The tractor launcher PD-10 will act as a motor. On the launcher, you need to install an air-cooled cylinder, which can be taken from the IZH-56 motorcycle. As for the fuel tank, it should be located under the engine. Fuel supply will be carried out by gravity.
An alternative option for the manufacture of snowmobiles
Homemade snowmobiles can be made using another technology. As in the first case, they will be single, but they will have to be equipped with four skis. In this case, one should adhere to the main principle, which is expressed in the use of as few scarce materials as possible. This will significantly reduce the cost of the design and make it as simple as possible. In this case, it is recommended to pay attention to weight loss. Despite the fact that this design will have four skis, and not three, as in the previous version, it should be easier.
Case manufacturing
Homemade snowmobiles with a low-power engine are made in this case from bars. It is necessary to prepare before starting work and spruce boards, which should have a thickness of 16 mm. Skis must be mounted symmetrically with respect to two transverse boards. The front skis will be steerable. They will include brackets. Fastening must be carried out with an M10 bolt, which will act as an axis. The hearth responsible for control will be combined with the fork. The method of pairing the control levers of the left and right skis, as well as the control cable, will be rigid. The cable must be directed through the rollers, from there it will go to the steering column drum, where it is fastened with an M6 bolt. The transverse rod has tips at both ends designed to adjust the parallelism of the ski. The swivel bracket in the area of the axis on the front board passes through the bars, which have a section of 30x30 mm. Skis located at the back are fastened with corners and M10 bolts.
Features of ski manufacturing
Before you make homemade snowmobiles, you need to study the design of the skis. It must be boxed. Using galvanized iron intended for roofing, you need to make a running sole. It is necessary to choose iron, the thickness of which is 1.2 mm. Two undercuts should be mounted on the sole, which must be made from a metal corner, it must have dimensions equal to 8x20 mm. With the frame of the ski, they must be paired with screws that have countersunk heads. A toothed steel scraper, which must be mounted on a steel wooden lever, mates with the brake pedal. If you press it, the lever will be lowered, and the toothed scraper will provide braking to the structure, while it will crash into the snow. The brake will be returned to its natural position by a spring.
motor part
Homemade snowmobiles, the drawings of which are to be considered even before starting work, must be made with a motor that is similar to that installed on the model described above. The engine must be installed with the cylinder down. Using strip steel, you need to make a sub-rack. Metal elements 8x30 cm in size will have to be prepared in advance. The gas tank must be mounted above the engine, fuel will be supplied by gravity. Ignition is provided by an aggregate magneto. The ignition timing is adjusted by turning the magneto bracket. Using a tin can, you need to make an air collector, which should be placed on the carburetor. The inlet of this element must be closed with a filter, which must be assembled from a steel mesh. The latter is laid in 10 layers. This manipulation will prevent splashing of the engine and the ingress of snow into it. Home-made snowmobiles with a Lifan engine will allow you to enjoy winter hunting and fishing.
Homemade snowmobiles for the fisherman. Firstly, the suspension of the power unit (and not installing it, as usual) Secondly, the steering of the "cart" type - it is carried out by turning not only the skis, but the entire front axle. And the last. The return of the controlled bridge with skis to its original position and keeping it on the straight course is carried out not so much by the steering wheel as by the torsion bar, which acts as a safety arc. Describing the design of the snowmobile, I’ll immediately make a reservation: due to the lack of argon welding, all joints of parts in the assemblies had to be bolted using bushings and brackets, and in some places riveted.
Frame homemade snowmobile spinal type - single-spar. Docked and connected to the side member, the rear axle beam and the motor mount stand are reinforced with struts. The connections of the frame strength elements are mainly detachable. I made them like this for disassembling the snowmobile and a very large frame for compact summer storage. The spar and the rack are made of a duralumin tube with a diameter of 70 mm with a wall thickness of 2.5 mm, and the rear axle beam and struts are also made of a duralumin tube, but with a smaller diameter and wall thickness - respectively, 40 mm and 1.5 mm.
The role of the struts of the engine mount is also played by the handrails of the seats, although they can only be called handrails conditionally - they are hung on the lodgements of the driver's and passenger's seats, knocked out of a duralumin sheet 2 mm thick. The seats themselves are made of a thick foam sheet and lined with tarpaulin fabric. Another element of the snowmobile can be attributed to the frame - the safety arc. It is made of two segments of a duralumin pipe with a diameter of 50 mm and a wall thickness of 2 mm joined by overlays.
However, it would be better to make the arc from a single pipe (unfortunately, I didn’t have one at the time of manufacture) because it also serves as a shock-absorbing suspension of the front steering axle and is a kind of strut strut. But about the arc - later. As for the controlled bridge, as on a cart, I did not make a reservation. It was its simplicity that prompted me to return to this already forgotten steering scheme, besides, it was very combined with a shock-absorbing roll bar and a single-spar frame. The front axle is connected to the front end of the spar by means of a kingpin and a silent block (rubber-metal bushing), the body of which is inserted into the front hole of the spar pipe.
The pivot is an M22 bolt. The connection of the front axle with the safety arc (it is also a torsion bar) was not carried out directly, but by means of removal - a cantilevered bridge fixed in the middle (perpendicular to it) of a pipe segment with a diameter of 40 mm and a wall thickness of 1.5 mm. The free (front) end of the extension is also connected to the front end of the safety arc with a “two-cheek” triangular bracket. The extension length was determined experimentally, within 200–250 mm. Its shorter length impairs the "vane" - the self-holding of the car on a straight course, and the longer one makes it difficult to control the snowmobile (turning the steering wheel).
By the way, to make it easier to turn the steering wheel, I subsequently attached a silent block to the end of the torsion bar (although it is possible to help with legs, as on an airplane). When turning the steering wheel, and, consequently, the front axle with skis, the safety arc deviates to the side, and even twists slightly. After removing the force on the steering wheel, the arc tends to return to its original position, keeping the skis on a straight course. The steering wheel itself is of a motorcycle type, only it is fixed on the bridge at three points through the lever struts.
From the steering wheel along the torsion arc, a cable for controlling the "gas" of the engine is laid. Skis are mounted on the axles at the ends of the front axle (as well as the rear axle). To protect against side impact, the skis are additionally attached to the bridges with struts (it would be better with shock absorbers) through bearing bushings: the front - two, the rear - one (in the back) and rotate in a vertical plane along with the skis. Homemade skis - all the same. Riveted from 5 mm sheet duralumin grade D16T with aluminum rivets. To give rigidity in the middle of the ski, a longitudinal strip-wall is welded, and strip struts are also welded to the wall. The outsole is made of a 5 mm thick polyethylene sheet and 10 mm wider on each side.
In the bent part of the toe, the sole is attached to the ski with rivets, and along the length it is simply pressed with a cut from a steel corner so that the sole does not warp due to the difference in thermal expansion. A small part of the rear end of the ski, together with the sole, is also bent up by 50 mm. At the ends of the beams of the bridges, the skis are mounted on rolling bearings, the bodies of which are fixed on the ski racks. The propeller installation itself is traditional and consists of a power unit from the Buran snowmobile with a capacity of 28 hp. and homemade constant pitch pusher propeller. Screw with a diameter of 1400 mm, wooden blades with metal fittings at the ends.
The maximum thrust created by it on the spot is about 95 kgf, which allows the snowmobile to reach speeds of up to 70 km / h on the ice of a frozen river. The transmission of torque from the engine to the screw is carried out through a four-strand V-belt transmission. The diameter of the drive pulley is 205 mm, and the driven pulley is 380 mm, that is, the gear ratio is 1.85. The tension of the belts is carried out by turning the eccentric axis in the sleeve, followed by fixing one in the other with a clamp. Mounting the power unit on the frame is not quite common. Firstly, it is not installed on it, but suspended on a cantilever beam and attached to it through rubber bushings.
In addition, the beam is hinged to the rack through the silent block. The additional fastening of the engine to the frame is completely extraordinary - with braces - with aviation flexible cables with a diameter of 4 mm with tension tenders. Such a suspension of the propeller installation on the frame practically eliminates the vibration of the snowmobile. There is no propeller guard yet, of course, a rotating propeller is a dangerous thing. But if you make a simplified fence, then it can play a “cruel joke” with the person operating the sled, and even more so with the passenger.
Psychologically, they will think they are protected. In fact, the likelihood of injury from a rotating propeller remains. If we are already making a fence, then it is complete - in the form of a thin lattice on both sides and around the circumference. And so that the propeller does not touch the snow, especially ice, when the rear of the snowmobile falls, a tail is made - a thinner pipe is inserted into the rear of the spar. Dry weight snowmobile is about 140 kg. Full curb (two people and 20 liters of fuel) - approaches 300 kg. The snowmobile has no brakes, the stop is carried out quite quickly due to the friction of the ski soles on the snow after the "gas" is released.
Snowmobile with a suspended propeller group and a "cart" front axle(details of all positions, except where otherwise specified, are made of D16T duralumin): 1 — engine (from the Buran motonart), 2 — four-strand V-belt transmission (i = 1.85); 3 - propeller with a diameter of 1400 (wood with metal end edging), 4 - cantilever beam, 5 - upper bracing of the engine mount (steel cable with a diameter of 4.2 w d), 6 - main rack (pipe with a screw diameter of 70 × 2.5), 7 — bracket for connecting the safety arc to the rack (sheet s5, 2 pcs.). 8—upper part of the safety arc (pipe with a screw diameter of 50×2), 9—fastening of the gas cable to the safety arc (rubber, as needed), 10—connecting bracket for parts of the safety arc (sheet s5, 2 pcs), 11—inclined part of the safety arc ( pipe with a diameter of 50 × 2); 12 — spar (pipe diameter 70×2.5); 13—steering wheel (motorcycle type), 14—central steering column (steel pipe with a diameter of 28); 15- side steering column (pipe with a diameter of 14, 2 pcs); 16—silent block of the roll bar (from the washing machine), 17—junction of the roll bar and the front axle (sheet s5.2 pcs), 18—removal (pipe with a diameter of 30 × 1.5), 19—side brace of the rack (pipe with a diameter of 40 ×1.5, 2 pcs.), 20 - rear passenger seat (foam rubber in a fabric cover); 21 - back seat lodgement (sheet s5), 22 - handrail-strut (pipe with a diameter of 30 × 1.5, 2 pcs), 23 - front seat lodgement (sheet s5); 24 - front seat (foam rubber in a fabric cover), 25 - gas cable (from a motorcycle); 26—lower extension of the engine mount (steel cable 4, 2 in diameter); 27—thunder (2 pcs), 28—fuel tank (20 l), 29—tail-hook (pipe diameter 64), 30—rear axle, 31—rear ski (2 pcs). 32—platform mount (cord, 2 pcs.), 33—platform (fabric "avizeent", 2 pcs.), 34—front steering axle beam (pipe with a diameter of 40 × 1.5.2 pcs.), 35 - front ski (2 PC)
Rear axle and its connection to the frame: 1—spar, 2—bracket-clamp for fastening to the spar of the cross member of the seat frame and struts of the rear axle, 3—crossbar of the seat frame, 4 strut, 5—ski, 6—bracket-clamp for fastening to the rear axle of the struts, 7—sleeve for fastening to the rear ski strut bridge, 8 - rear axle beam (2 pcs), 9 - strut strut (2 pcs), 10—seat frame, 11—main rack; 12 — a loop of fastening of the basis of a seat to a frame (10 pieces); 13 — bracket-clamp for fastening to the seat frame and motor mount, 14—bracket for fastening the side member to the main rack, 15—sleeve for fastening the seat frame to the side member and the main rack (2 pcs.); 16 - beam connecting bracket (2 pcs)
Front axle and ski: 1 - base of the ski, 2 - brace of the ridge. 3 - arch, 4 - ridge; 5- rivet; 6-front strut strut (2 pcs), 7—rear strut strut (2 pcs), 8 housing with rolling bearing, 9—stand, 10—eye for fastening the ski strut to the ridge (2 pcs), 11—shoulder with fork, 12 rear strut of the ski (2 pcs), 13 - bushing for attaching the strut to the bridge beam, 14 - half-foot bracket; 15 bridge beam, 16-spar, 17-hinge connection of the bridge beam and the spar, 18 - bracket for connecting the beam and stem, 19-bracket for connecting the stem and roll bar, 20- footrest
Suspension of the power plant on a cantilever beam and cable braces: 1 - eccentric axle, 2 - bushing (steel, pipe with a diameter of 50 × 2), 3 - clamp with a clamping bolt, 4 - tie of the upper braces (rubber band), 5 - upper braces, 6 - cantilever beam (steel pipe with a diameter of 40 × 1.5), 7-axis of the hinge (M16 bolt), 8—silent block, 9—sleeve-bracket for mounting the motor mount on the main rack, 10—main rack; 11 — engine mount to the cantilever beam (4 pcs.), 12 — engine, 13 — bushing stand, 14 — bushing strut (2 pcs.), 15 — beam wing (4 pcs.), 16 — engine output shaft. 17 - lower extension (cable with a diameter of 4, 2 pcs.), 18 - thunder (2 pcs.), 19 - bushing-gasket (rubber, 4 pcs.)
Manufacturing technology of a wooden propeller for snowmobiles
For the manufacture of block wooden propellers, solid straight-grained types of wood without knots and rot are used - oak, maple, ash, beech, etc. It is not recommended to make a screw from a whole blank, as it can warp over time and significantly distort its original shape. It is best to glue the blank for the screw from thin (10-12 mm) boards - gorse. To prevent warping of such a blank, the boards must be well dried before gluing. They need to be glued with the inside of the wood to each other, like a fan (Fig. 70, a).
Gluing is preferably done with casein glue with holding the blank under pressure (it can be under load or under tightening with clamps) for at least two to three days.
The dimensions of the blank should correspond to the overall dimensions of the future screw with a small allowance.
The blank is first of all filed along the contours of the screw. To do this, the screw contour templates are cut out of plywood in accordance with the dimensions of the drawing along its two projections (Fig. 70, b).
According to the templates, a blank is marked, strictly observing the coincidence of the axes on the blank and the templates. The marked blank is cut along the contours (Fig. 70, c) and a central hole is drilled, along which the screw will be centered in the future. The hole is cut exactly perpendicular to the plane of the blank. If an intermediate part has already been made - the screw sleeve, through which it will be mounted on the drive shaft, then the ends of the sleeve are finally processed and a screw blank is bolted onto it.
For precise processing of the blades, it is necessary to make a slipway and templates for all sections (arms) of the blade.
A thick, dry, well-planed board with a size of at least 2/3 of the screw length can serve as a slipway. The axis of the screw is marked on it and risks are applied at the installation sites of the control sections - the arms.
On the slipway, it is necessary to install an axial pin exactly along the axis of the screw, which will imitate the screw shaft. A screw blank is put on this pin so that it does not lie closely on the slipway. To do this, the axial pin is placed on the lining.
For each control section of the blade, a template is made, consisting of two parts - lower 1 and upper 2.
All lower templates must be calculated by their height from the plane of the slipway, taking into account the thickness of the lining placed under the axle pin. If this is not done, then it will not be possible to make a screw with the required accuracy.
The upper template must exactly fit and be centered on the lower template, for which, during manufacture, it is sawn along the control areas of the lower template and control risks are applied simultaneously on both templates. Install the lower template on the slipway between the wooden blocks.
Rice. 70. Technological scheme for the manufacture of a block wooden propeller.
The processing of the blades is carried out sequentially, controlling the correctness with only one template, that is, made in one copy for each section. It is advisable to make templates for controlling the section of the temples from thick duralumin 3-5 mm thick.
Before starting the processing of the blade, it is necessary to make sure that the screw blank on the axial pin has no play. At the same time, it is necessary to check (by arbitrarily chosen points on the blank) that the blank is not skewed on the slipway.
A roughly machined screw is cleaned with glass fragments and sandpaper, achieving a good fit to its surface with control cross-section templates.
propeller balancing. Balancing a propeller is one of the important steps in its manufacture. This is especially true for multi-turn and variable pitch propellers. In the latter, the blades and a significant number of parts change their position in space during operation, which can violate the aerodynamic and weight symmetry of the propeller.
In operation, a poorly balanced propeller causes shaking and vibration of the motor assembly and housing. This can lead to loosening of fasteners, the appearance of cracks in the nodes and pipes of structural structural elements and to premature wear of the engine, equipment and the propeller itself.
Weight imbalance is characterized by a shift in the center of gravity of the screw from its axis of rotation, due to which the centrifugal forces on one blade will be greater than on the other.
The magnitude of the weight imbalance is expressed in grams at a screw radius of 1 m. It is measured and eliminated on a knife balancing device.
The unbalance of the weight moments is determined by the non-parallelism of the small main axis of inertia of the screw with the axis of its rotation.
Causes of weight imbalance: deviation of the dimensions of parts from normal (even if they are manufactured within tolerances) and distortion of the shape of the blades under load by centrifugal forces. Weight unbalance is checked on a balancing device made of two well planed boards and carefully calibrated when leveling.
The imbalance of the aerodynamic forces is determined from the condition that the resistance forces to the rotation of individual blades are not the same, and the imbalance of the moments of the aerodynamic forces is determined from the condition that the moments of the thrust force of the individual blades relative to the axis of rotation are not the same.
The reason for the aerodynamic imbalance is the deviation of the installation angles of individual blades and their sections, which change the aerodynamic characteristics of individual sections on the blade and the blade as a whole. The aerodynamic imbalance on the slipway is checked by fine-tuning the control sections of the blade according to the same template for all blades.
Balancing during the manufacture of the screw is carried out at least three or four times (after the manufacture of the screw and its cleaning, after puttying and gluing with cloth, after applying each layer of paint).
If the propeller exhibits weight deviations, these can be corrected by applying an additional coat of paint to the lighter blade (for a wooden propeller) or by sanding the heavier blade (for a metal propeller)*
Paint the screw with oil paint over the primer layer. After applying at least two thin layers of paint, the screw is polished and coated with oil varnish.
The ends of the wooden blades are bound with a thin metal sheet of brass or stainless steel to ensure the strength of their working edge.
How to do do-it-yourself aerosleighs. Snowmobiles have always been one of the most popular homemade vehicles. The reason for this is the relative ease of manufacture (aerosleighs do not have wheels, complex transmission, hydraulic brakes, clutches, etc.) and efficiency of use (aerosleighs can pass at high speed where only a caterpillar tractor can crawl). However, the relative simplicity of the design of a vehicle with an aerodynamic propulsion introduced many home-made people into the temptation of creating a primitive apparatus. As a result, although such sledges could move, the creator did not get pleasure from riding. And most often this was due to an ill-conceived aerodynamic layout.
About power plants with a pusher propeller, amateur designers sometimes create the wrong opinion that if there are no obstacles to the air stream thrown back by the propeller, then its efficiency is higher than that of snowmobile with a pulling screw, and thrust, respectively, more. However, this is not the case. It is necessary to organize the air flow aerodynamically not only behind the propeller, but also in front of it, since the “torn”, turbulent flow distorted by structural elements that falls on the blades can reduce the efficiency of the propeller so much that it will never be able to develop the expected thrust. In the proposed design, an attempt was made to create comfortable snowmobile, which have extremely reduced aerodynamic losses.
The task is quite difficult. I wanted to design a two-seater vehicle with the location of the driver and passenger in the car, and this arrangement has a solid midsection. Nevertheless, this is still preferable to the tandem layout - the snowmobiles turned out to be more compact, with the usual proportions corresponding to cars. After drawing the interior and arranging the propeller installation (it was supposed to be placed as low as possible in order to lower the center of gravity of the machine), the hull began to suffer - its surfaces had to be made aerodynamically smooth, without sharp bends. The result was a design reminiscent of the post-war domestic car Pobeda.
The desire to reduce aerodynamic losses led to the organization of the supply air channel, ending in a half ring, which also served as a propeller guard. As a result, a body of a rather complex shape was obtained, which, nevertheless, turned out to be quite justified both aerodynamically and aesthetically. The base of the snowmobile is the bottom frame-panel. It is glued together from pine spars, wooden cross-beams, foam filling and plywood working sheathing. Such a panel, with a small thickness and low weight, has high rigidity, both in bending and in torsion.
For the spars, straight-layer boards 40 mm thick were selected, from which curved blanks about 50 mm high were cut. The sidewalls required 15mm boards, and the front crossmember, on which the steering pivots are mounted, required a 60x50mm pine block. The frame of the frame-panel is assembled with epoxy glue. The same binder was also used when gluing foam blocks into the frame, as well as facing the bottom panel with 5 mm plywood. Frame snowmobile made according to the classic technology for home-made designs. It consists of a light frame, welded from thin-walled steel pipes with an outer diameter of 15 mm, on which plywood shaping elements - stringers are fixed with soft wire.
The windshield is from ZAZ-968, the frame for it is fixed to the frame by welding. The space between the stringers is filled with foam blocks; after processing the foam and puttying the surface, the body is pasted over with two layers of fiberglass. The doors are made using the same technology as the body - with a tubular frame, plywood stringers and foam filling. The rear window and door windows are made of 4 mm plexiglass. The sides of the rear part of the body, passing into the keels (areas behind the doors), are lined with sheets of 4 mm plywood, fixed to the tubular frame with M4 screws, followed by pasting the outer surfaces with two layers of fiberglass. The inner part of the plywood sheathing is coated with two layers of parquet varnish to increase moisture resistance.
The basis of the propeller installation was the rather well-developed RMZ-640 with a V-belt gearbox, which was very popular with amateur aviators. Many trikes, gyroplanes and airplanes are equipped with such engines. By the way, the propeller installation of the snowmobile practically does not differ from that designed at the time by the student of the Moscow Aviation Institute A.. Rusak for a two-seat hang-glider. With a propeller with a diameter of 1350 mm, the power unit develops a static thrust of about 120 kg, which is quite enough for a snowmobile. The propeller unit on a three-dimensional frame-panel is fixed with six braces made of steel pipes with a diameter of 30x1.5 mm.
To reduce aerodynamic resistance, wooden fairings are glued to the pipes with epoxy resin, giving the braces a drop-shaped section. The propeller is made using a technology similar to that used by the German company Hoffman. A screw blank made of pine blocks with a section of 60x20 mm is glued with epoxy resin. When gluing the bars, the layers of wood were located symmetrically relative to the planes of joining - this saved the propeller from possible leashes. After gluing, the workpiece was carefully planed in accordance with the dimensions of the screw. For the manufacture of templates, a theoretical drawing of the propeller on a scale of 1:1 was used. The templates themselves are cut out of plywood, but it would be better to make them from duralumin.
To work, we needed a plan template, a side view template (up to the axis of rotation), as well as upper and lower propeller blade profile templates. Blade profile - plano-convex, winged. The workpiece is marked with the help of a planned template fixed with a nail in the center of the future screw: the template is circled in pencil, rotated 180° and circled again - the contour of the second blade is obtained. Further, in accordance with the markup with an ax and a planer, the blades are pre-processed. Finally, the screw was finished in the slipway. Its base is made of a flat board 60 mm thick, on which, in accordance with the theoretical drawing of the propeller, the lower blade profile templates and the central rod are installed. The latter is fixed in the center of the base perpendicular to its surface.
The accuracy of the processing of the screw was checked with the help of blue, which was rubbed on the lower templates: the workpiece was put on the rod and pressed against them, while traces of the templates were imprinted on the blade. After removing the blue traces with a rasp, the future screw was again pressed against the templates - and so on until the traces of all the templates along their entire length were imprinted on the workpiece pressed against the templates. The upper part of the propeller is machined in a slipway according to the upper templates - first, in each section, using a semicircular rasp, the blade was sawn along the corresponding upper template so that the upper and lower template touched along the parting line, while covering the blade itself.
Then the excess material between the sections was removed - the correctness of this operation was controlled by a metal ruler applied to the percentage points of adjacent sections - processing was carried out until the gap between the ruler and the blade surface disappeared. The finished screw was carefully balanced, for which a metal roller was inserted into the central hole and the propeller was mounted on balancing rulers. The lighter blade was loaded with lead - small strips of this metal were first glued onto it, and when the screw was balanced, a casting was made from the strips in the form of a round rod, inserted with epoxy glue into a hole drilled in the blade, where the lead strips were located during balancing, and riveted .
Finishing the propeller consisted of gluing it with two layers of thin fiberglass, followed by grinding, final balancing, priming and painting with car enamel. The front ski is epoxy glued from strips of 4mm plywood and a strip of stainless steel 0.8mm thick. The total thickness of gluing is 30 mm. The front of the ski is equipped with an arc bent from a steel pipe with a diameter of 16 mm. In the middle part of the ski, guide undercuts are fixed, cut out of 3 mm thick stainless steel sheet. The ski is equipped with a spring-hydraulic shock absorber from the Ural motorcycle.
The rear skis are box type. Their soles are glued from 4 mm plywood and 0.8 mm stainless steel (the total thickness of the gluing is 20 mm), the sidewalls are cut from 25 mm boards. Rear skis have no cushioning. Steering - with a rack and pinion mechanism from a motorized carriage FDD. By the way, the heater was also used from it. Brakes - scraper type, mounted on the rear skis. The brake drive is combined: from the pedal to the intermediate lever - cable, from the lever to the scraper - rigid, tubular traction. The carburetor throttle drive is from the lever under the driver's right hand. The lever is equipped with a locking button (as on a car handbrake), which allows you to stop it in any intermediate position.
Double snowmobile with PMZ-640 engine: 1 - headlight (from Izh motorcycle): 2 - windshield (from ZAZ-968); 3 - side glass (plexiglass s4); 4 - RMZ-640 engine with a V-belt gearbox; 5 - propeller: 6 - position lamp; 7 - scraper brake; 8 - rear ski; 9 - rear window (plexiglass s3); 10-corps of snowmobiles; 11-volume frame-panel; 12- door; 13 - rotary column of the front ski; 14 - front ski "; 15,16,17 - braces of the propeller installation (steel pipe 30x1.5)
Snowmobile frame-panel: 1 - lower panel lining (s5 plywood); 2 - filling (construction foam); 3 - top panel lining (plywood s5); 4 - rear cross member (pine, bar 60x50); 5- amplifiers (pine, bar 30x30); 6- the central part of the middle crossbar (pine, bar 60x50); 7- front beam (pine, bar 50x60); 8.10-spars (pine, board s40): 9 - front cross member (pine, board s30); 11 - sidewall (pine, board s15); 12- sidewall of the middle cross member (pine, bar 60x50.2 pcs.)
The front ski of the snowmobile: 1 - suspension pendulum bracket (steel); 2 - axis of the pendulum (steel, pin M16x 1); 3 - suspension pendulum (steel, pipe 22x3); 4 - spring-hydraulic shock absorber (from the Ural motorcycle); 5- safety arc (steel, pipe 16x2.5); 6- pipe fastening (M6 bolt with nut and washer); 7 - ski base (plywood s4, stainless steel, sheet s0.8); 8 - fastening of the safety arc (self-tapping screw with a diameter of 5); 9- housing of the suspension pendulum hinge (steel, pipe 30x2); 10-hinge bushing (fluoroplast); 11 - bracket (steel, sheet s4); 12 - shock absorber support mounting (M8 bolt with nut and washer); 13 - undercut (stainless steel, sheet s3); 14- shock absorber mounting (M8 bolt with nut and washer); 15 - shock absorber support (steel)
Propeller installation of snowmobiles with a wedge-shaped gearbox: 1 - RMZ-640 engine; 2 - gearbox bracket; 3-air screw with a diameter of 1350 mm; 4 - driven pulley of the gearbox; 5 V-belt; 6 - drive pulley of the gearbox
V-belt gearbox: 1 - gearbox bracket (duralumin, corner with s5 wall); 2- propeller; 3 - driven pulley (aluminum alloy AK-6); 4 - the axis of the screw with an eccentric device for tensioning the reducer belts (steel Z0KhGSA); 5- bearing 36206; 6 - dustproof ring; 7 - threaded bushing (steel Z0KhGSA, 4 pcs.); 8 - axial bushing (steel Z0KhGSA); 9 - support washer (steel, sheet s4); 10 - M8 bolt with a split spring washer (4 pcs.); 11 - retaining ring; 12-bearing 60205; 13 - drive pulley (kaprolon); 14- M6 bolt with a split spring washer (6 pcs.); 15 - shank of the crankshaft of the engine; 16-belt; 17 - adapter (steel Z0KhGSA); 18 - wedge; 19 - bearing 60206; 20 - sealing sleeve (30KhGSA steel, pressed into the engine crankcase); 21 - stuffing box; 22 - sealing ring (rubber); 23 - bearing 206; 24 - M8 bolt with a nut and a split spring washer (4 pcs.); 25 - support-clamp key
Snowmobiles are used where there are no roads or a tractor can hardly pass. This homemade vehicle does not have a clutch and a complex transmission. There are also no hydraulic brakes, so the snowmobile is easy to make with your own hands.
In winter, fishermen have to travel long distances. The use of home-made equipment makes the transfer to the reservoir quick and convenient. The vehicle is equipped with skids, thanks to which it is possible to move on ice, crust and snow. The snowmobile drives an aircraft propeller. It spins a motor that runs on gasoline.
When driving, the sleigh develops a speed of up to 150 km / h. This is what sets them apart from snowmobiles. With a soft suspension, the transport provides a comfortable ride. If we talk about the smoothness of the ride, then the snowmobile is comparable to a car. Cabins are often installed on them, this gives additional protection from wind and frost.
The bottom frame serves as the base of the structure, it is made in the form of a panel. The frame is assembled from spars, it is best to use pine. A foam filler is also required, and the rigidity of the structure is given with the help of wooden crossbars.
The frame is sheathed, for this purpose it is necessary to purchase a plywood sheet. Together with torsional bending and high rigidity, it demonstrates high quality characteristics.
Specifications
Homemade snowmobiles are better than snowmobiles; do-it-yourself snowmobiles for fishing can be made by installing a motor with a power of 15 hp or more on the structure. It is so easy to achieve the following indicators:
- In 1 minute, the engine makes 4700 revolutions.
- The screw diameter is 1300 mm, it spins up to 2300 rpm. Maximum force - 62 kg.
- The fuel tank holds 40 to 50 liters of gasoline.
- Without a driver, the weight of the structure is 90.7 kg. With a load - 183 kg.
The choice of engine depends on the mass of the snowmobile, its size and carrying capacity. The motor must be of such power that the propeller makes the required number of revolutions. This value is selected by the designer. It is necessary to strive to ensure that the design is light, then you can install an engine of small size and power. The equipment must have an air cooling system.
An automobile motor is often put on a snowmobile. It is distinguished by high power, it is easy to equip home-made snowmobiles with an engine, because it is enough to remove it from an old car.
You can install a motor from a Jupiter motorcycle on a sled, an engine taken from a Zhiguli would be a good option. You can use K-62I. This is a carburetor that has 2 cylinders. Ignition is carried out from the battery, and the fuel tank is designed for 30 liters of gasoline.
On light snowmobiles, you can install D-30 or D-15. The first develops a traction force of 40 kgf, and the second - 60 kgf. D-15 has a gear reducer. On both engines, the tank is designed for 15 liters of fuel.
load capacity
Carrying capacity refers to the ability of a vehicle to move goods and passengers. This is the total weight of the vehicle, including ammunition and people. Homemade units are designed to carry from 1 to 5 people. With a load, the weight of the snowmobile reaches 300 kg.
Range and movement speed
If you install a 15 hp engine on a snowmobile, they will develop a speed of 70 to 80 km / h on hard snow, the average speed is 40-50 km / h. Speed on rolled snow increases. The fastest transport travels on the crust, the maximum speed on snowy terrain can be 110 km / h. But at high speed, the stability of the equipment decreases, it is likely that it will tip over. Therefore, it is not recommended to reach speeds above 50-70 km / h.
Most often, tanks with a capacity of 40 liters are installed on home-made vehicles. Filled with fuel is enough for 300 km.
Fuel supply
Since the snowmobile travels in areas where there are no gas stations, it is necessary to take care of the fuel supply. It is poured into a canister, it is best to use containers with a volume of 20 liters. This stock will be enough to get out of the snowy wilderness.
Brake design
The braking system of home-made equipment cannot be called classical. Scrapers are made at the ends of the rear skis, cables are pulled from the brake pedal, which, if necessary, actuate them. When the driver presses the pedal, the scrapers move down. Because of this, the progress of the sleigh slows down.
How to DIY
Snowmobiles can be made with your own hands: the bodies of homemade snowmobiles are created taking into account the laws of aerodynamics, so all elements of technology should be done in strict accordance with the plan. The work of all components and the service life of home-made equipment directly depend on the quality of the assembly.
Drawing of typical snowmobiles: 
Frame
The assembly of the snowmobile begins with the body, it consists of a solid frame, which is covered with a sheathing. It is given an aerodynamic shape, making a narrowing towards the front. The case has 2 compartments: front and rear, in which the motor is installed.
The necessary structural rigidity is provided by 2 spars and power stringers. Frames are installed, there should be 4. They are placed at regular intervals. Plywood is used for their manufacture, it is best to purchase material with a thickness of 10 mm. Wide frames are reinforced with transverse beams.
Work begins with the installation of the lower frame, frames are installed on it. Be sure to make spacers, they are fixed to the frames with the help of corners. When this stage is completed, they proceed to fixing the stringers. Transverse reinforcement with special beams is necessary, because goods are transported on home-made equipment.
The frame is glued, this can be done by applying casein glue. Gauze is applied to the joints, then it is impregnated with glue. Another option is also possible, when the gauze is first cut, the bandage is impregnated with glue, and then the joints of the elements are wrapped with a strip.
For sheathing the hull, sheets of plywood should be purchased, they are covered with a duralumin coating on top. The driver's seat is made of plywood, but you can install a factory one made of plastic.
A place for cargo is allocated in the rear of the structure, located behind the seat. Spare parts and tools can be stored in this compartment, a canister of gasoline, fishing tackle and passengers' belongings can also fit here. There are different options for assembling an aerosleigh transport, design drawings should be studied before starting work.
Propeller system
The propeller system consists of several elements. The most common option is to install a motor removed from the IZH-56 on a snowmobile. The screw shaft is mounted on the bearing, it is mounted on the frame. A wooden plate is required to mount the engine.
To regulate the V-belt transmission to the screw, a plate made of plywood or textolite is required. A fan is installed to cool the engine. It is fixed on the crankcase using a bracket for this purpose.
Suspension
Skis for snowmobiles are made of plywood 10 mm thick, they are sheathed with stainless steel from below. Skis are bent; for this, plywood is placed in boiling water. Bending is done using a slipway.
When assembling, it is necessary to correctly select the thickness of the rear skis, various drawings are given. For reinforcement, a thick beam is used, the skis are attached to the body with M6 screws. In order for the snowmobile to be stable when cornering, undercuts are made. They are constructed from a pipe flattened at the ends.
How to properly equip?
The speedometer, ignition switch, fuel gauge and all major instruments are mounted on the front panel. There should also be control levers, brake pedals and engine start. If you are planning trips to unfamiliar places, far from populated areas, you should install a GPS navigator on the snowmobile. A rear-view mirror is placed on the left, the air and throttle lever should be in the cab.
Snowmobile with a chainsaw engine
The chainsaw motor has a low power, which does not exceed 4 hp. This is not enough to travel long distances. The minimum engine power must be at least 12 hp.
If the reservoir is nearby, then a low-power motor is enough. The motor from the chainsaw, despite this, will budge the lightweight structure. Such snowmobiles can be used to transport fishing tackle.
Alternatives
An automobile body can be used as a body for a snowmobile.
Here, for example, an aerosleigh made from a "loaf".
Safety during operation
When operating home-made vehicles, a propeller poses a potential danger to passengers. To prevent accidents, the propeller screw is hidden in a shroud. This element protects not only passengers, but also the propeller itself from foreign objects entering it.
When assembling a snowmobile, you should control the quality of work. The main load falls on the skis, so the quality of the bolted connection must be high. Fasteners need to be checked, timely maintenance should be carried out. The propeller is regularly inspected, it is important to see the defects that have arisen in time.
Trouble-free operation of equipment is possible if the engine for the snowmobile is working normally, there is fuel, oil is poured to the desired level.
When assembling equipment, they are guided by the dimensions presented in the drawings. Be sure to make the cabin a visor, then the snowmobile becomes more convenient to use. It is not necessary to make changes to the design, this may cause malfunctions.