A CATAMARAN WITHOUT SAILS AND OARS

Recently outboard motor was held in high esteem by the water-tourists. However, in recent years a large part of the waters became inaccessible for boats with internal combustion engines. Once again had to recall the sail, to once again take up the oars — Many, however, are not satisfied with traditional propulsion with a muscular drive efficiency the same oars is not too high. No wonder at the time, the paddle wheels were literally pushed by a propeller.

However, the screw is accustomed to seeing in a pair of the internal combustion engine than with bike pedals, but the effectiveness of such combination of mechanisms is quite high, at least much higher than traditional paddles.

One of the most successful works in this direction can be considered as a catamaran-aquapad design Kharkiv V. Popovich (his photographs were published in the August issue of “M-K” for 1986). In response to numerous reader requests, publish a description of the design of this catamaran.

About the benefits of folding designs can say a lot, no wonder the last time professionals and technology enthusiasts creating collapsible bicycles and motorcycles, boats, transforming planes and trikes. This is natural — the problem of storage and transportation is greatly simplified, if the vehicle is foldable.

For your family “craft” I chose the structure of a catamaran with inflatable balloon-floats. It successfully solved the problem of stability equiped and transformation of the boat in an easy to transport package. The engine was elected to the propeller driven by Bicycle type pedals. The transmission of torque to the screw through the gear made of the mechanism of hand drill. The hydrodynamic screw is within the ring, which allowed to significantly increase the thrust of the screw.

Manufacturer catamaran-equiped suggest to start with the floats. The choice of the design depends on the existing materials.

Preferably the float is a tubeless type. Here, however, will require a durable rubberized synthetic fabric, which is not easy to acquire. Float with the camera it is difficult to manufacture and operate, however the materials more accessible: the shell is cut in the shape of tarpaulin or thick Dacron, and the camera wikiepedia of child (medical) oilcloth or sheet of elastic rubber. The size of the camera compared to the shell should be increased by 10-15%: not-so-tight pressurized, it will last longer.

Cutting the shell of the float shown in the illustration. For a catamaran will require four panels — two for each float. Note that the figure does not show the seam (when sewing overlapping, they constitute 30-40 mm per side), and also folds in front and rear of the shell needed to create a smooth, wrinkle-free surface.

To connect cut pieces of the best on the sewing machine, lap. Where to flash the joints of the machine can not afford (for example, bow and stern shells) of the cloth are sewn by hand machine stitching. His step — 4…5 mm.

After final grouting, the shell of the float is painted with a composition of gasoline, rubber cement, and aluminum powder. The obtained elastic waterproof paint gives the floats a beautiful appearance and reduces the heating of the sunlight. Such coverage, we note in passing that positively affects the handling characteristics of the catamaran.

To each shell is sewn four pockets — they are essential for the attachment of floats to the rigid frame. Pockets inserted in the cut dural tube Ø 8…12 mm, and it is passed a nylon cord. When you build a boat that floats draw cord to the frames frame.

In front of both cylinders is the valve through which capacity is filled with air. This site is homemade, it consists of a duralumin case where drilled 8 holes Ø 7 mm membrane, for which the best fit to the hull glued rubber gasket, steel springs and caps, rolled at the bottom of the valve body. The valve body is fixed to the shell by means of two washers before you install they are profusely lubricated rubber adhesive, after which the tissue between the washers natugo tighten the nut.

Pressure cap is screwed onto the valve body after filling the float with air. This threaded cap, which is located within the dural disc glued to it with rubber gasket. The space between the disc and the cover is filled with grease.

Pump for inflating floats also homemade. The fact that none of the pumps mass-produced, made quickly and easily fill the shell with air. My pump allows you to pump the tank half minutes.

I made it out of two plywood (thickness 6…10 mm) discs and rubberized shell. Inside is a standard furniture spring from the old mattress. Hose became a Cycling chamber, the inner diameter of which corresponds with the performance of the pump.

The catamaran framework is rigid; it consists of two side members corner section 40X20X2 mm, hinged front part (in open position it is held by locking mechanism), transverse kit and seat.

The transverse set is a three dural tube (material Т30Х1,5 mm) and two brace of dural pipes Т32Х1 mm. Foot frame and two internal frames from the pipe Т33Х1,5 mm onto the two deck pipes. In addition to frames, the rear pipe is attached to the installation unit of the engine of a welded construction of pipes Т33Х1,5 mm. All pipe cross -set joined with the longitudinal members of the parts — with the help of glasses, is bolted to longitudinal elements and zaspirtovannyh aluminum rods.

The end of the brace has a diamond-shaped slot corresponding to the shape of the head of locking bolt. When raising the stop in the working position is fixed in this locking bolt is rotated and thus the “buttons” brace. The legs of the seat are secured between the corners of the longerons. During disassembly of the catamaran, these elements are not removed.

The main structural elements of velocitymoney:

1 — float, 2 — valve, 3 — movable part of the longitudinal, 4 — bulkhead, 5 — spar, 6 — bridge, 7 — tiller, 8 — seat 9 — back 10 — turning device mover, the 11 — deadwood, 12 — starcrazy, 13 — strengthening seat, 14 — foot frame node, 15 — node dock float with the frames.

Seat with a folding backrest of dural pipes Т32Х1 mm pine slats section 10X20X1400 mm, mounted on cotton straps. Reiki is carefully sanded and coated with waterproof varnish. Belt tension in which the seat becomes quite hard, is achieved by folding the backrest.

Collapsible catamaran design V. Popovic (seat and the steering device is conventionally not shown).

Folding catamaran designed by V. Popovic (seat and the steering device is conventionally not shown):

1 — float, 2 — longitudinal, 3 — frame, 4 — sleepers, 5 — stern shaft, 6 — shaft tube, 7 — reducer, 8 — Bush roller chain, 9 — foot mechanism from the drive sprocket, 10 — focus lock for braces (pipe Ø 30Х1,5 mm), 11 — adapter (tube Ø 32X1 mm) 12 — locking bolt 13 is screw М3Х36 mm, 14 — sleeve (dural tube Ø 8…12 mm), 15 clamp, 16 — clutch 17 — M3 screw, 18 — bearing, 19 — universal joint, 20 — bearings of the screw shaft, 21 — spinner, 22 — screw shaft 23 — thruster, 24 — hydrodynamic ring, 25 — designated place, 26 — Travers, a 27 — through-stud, 28 — bracket, 29 end part of the brace, 30 — wire attenuator, 31 — limiter (tube Ø 30Х1,5 mm), 32 — brace 33 is welded connection 34 of the bracket brace, 35 — node installation of the propeller.

To consolidate the long slats of the seat in its middle part made gain.

The bridge of the catamaran recruited from 17 beech slats 15X25X430 mm. cross-section of Each rail is fixed on the cotton belt screws. At the ends of the straps are established from one side of the castle and on the other — clip. Buckle to such a castle, there is simultaneous stretching of the belt.

To drive the catamaran used part of the frame of the bike Tourist, two stars with a ratio of 4, and a gear mechanism hand drill with a push-button switch (gear ratio equal to 6). Pedals mounted on the crossbars — and for this to it is welded a steel tube. Welded to the frame of the pedal and also the bracket for mounting the tiller and two scarves with holes for M6 bolt — for mounting the frame of the gearbox.

Spar catamaran:

1 — М6Х50 mm bolt with nut, 2 — Cup, 3 — mount deck, 4 — textolite washer 5 — spacer (tube Ø 30Х1,5 mm), 6 — washer, 7 — tubular rivet (tube Ø 10X1 mm), 8 — spacer (tube Ø 10X1 mm), 9 — rivet Ø 5 mm, 10 — glass to frame, 11 — housing lock, 12 — tilt the front of the spar, 13 — spar (aluminum corners), 14 — front seats, 15 — back front seat, 16 — latch (OVS wire Ø 1,5 mm).

Seat:

1 — the lock of the front support seat, 2 — rail, 3 — brace struts, 4 — tubular rivet, 5 — plug, 6 — intermediate crossmember (pipe diameter 32X1 mm), 7 — tension clamp, 8 — bracket side of the pipe, 9 — tubular rivet, 10 — retainer 11 — retainer side of the pipe.

A. wiring schematic textile strap:

1 — slat seat and back, 2 — belt, 3 — tension clamp.

Pattern shell float (per float, two cloth).

The pattern of the shell of float (per float, two panels).

Bracket pedal mechanism:

1 — front pipe, 2 — clip, 3 — deck, 4 — solitaire.

Valve:

1 — housing 2 — screw tube, a 3 — membrane with rubber gasket, 4 — spring 5 — plug 6 — shell float, 7 — nut, 8 — pad, made of rubber and dural disks, 9 — washer.

The reducer should be replaced shaft first gear for longer to be able to install driven sprockets.

At the ends of the shaft mounted bearings, wearing steel cage-Cup, is welded to the ends of the spacer frame. Spindle drills protochen and wearing a stern tube shaft — duralumin pipe Т14Х1 mm. Shaft within the stern tube (Ø 32X1 mm): one end is provided with a bearing and the other secured to the housing of the drill. The purpose of this pipe is to remove the bending load in the connecting spindle of the driveshaft.

Between the stern tube with shaft and propeller shaft universal joint is installed, the main element of which brass biscuit with intersecting axes Ø 3 mm and Ø 6 mm.

Propeller — aluminum, cast, Ø 179 mm and 180 mm. step It rotates in a hydrodynamic ring with profile thickness of 12%. As shown by experiments, the use of rings increased the thrust (focus) of 20%. The ring is laminated of fiberglass and epoxy on the foam base. Its top ring is glued to the deadwood, at the bottom it is attached with two aluminum struts.

Steering cable: startree link rotary tiller with duplechin arm on the rudder stock. When you turn the tiller the plane of rotation of the screw can deviate from neutral to 30° right and left.

The catamaran has a good speed when pedaling with a frequency of 1 Rev/s, it reaches 10 km/h.

V. POPOVICH, Kharkiv

Recommend to read

IN ONE BACKPACK OR THREE
Looking at this unusual backpack, shown by the team of the Leningrad regional Council of tourism, you catch yourself thinking: how had not thought of before? Indeed, in a normal...
THE TU-154
Scale model 1:100. Tu-154 (NATO reporting: Careless — "Carefree," in the slang of Russian pilots - "Tupolev" or "Aurora" (from Avrora Cruiser), for three pipes - nozzles) — trimotored...