SKIING IN THE SAIL | MODEL CONSTRUCTION

The desire to ski “with the wind” makes us resourceful athletes to invent a new sport: racing on skis towed behind a motorcycle (skijoring), boat and even horse. Today, it seems we are on the verge of “opening” another form of skiing-a tow sport where the athlete has to match the skills of the skier with the ability to manage a sailboat on the tires with very low pressure. Such towing is already popular among fans of winter tourism, as they allow us to travel long distances without special effort on the part of the athlete.

A sailing ship is a two-wheeled cart with a couple of light tires with very low pressure

and rigging type “Bermuda sloop”, that is, equipped with two sails — a mainsail and a jib. This type of weapons allows the tug to go cool enough to the wind, which is very important when running downwind in open spaces when you have to move towards the wind. Windage ^ towing is about 7.5 m2, which allows the skier to move even with moderate wind.

Frame sailboat is a cruciform structure, welded of steel thin-walled pipes with a diameter of 50 mm. Connecting longitudinal (longitudinal) and transverse (- axis) of the beams is carried out using a diamond-shaped gusset plate and joint-braces of steel sheet of thickness 2 mm In the axis has two axles, fixed so-called plug lap joint.

Wheel of the sailboat are welded from steel tubes with a diameter of 12…16 mm. Before dealing with their production, we should clarify what tires are you going to “Shoe” your wheels, and to align the sizes of openwork disks with geometric parameters of the rubber cameras. The wheel consists of a welded together of the sleeve (cut steel pipe) and steel ring. After welding in the bushing chiseled the holes for the bearings n 204. For welding the hub and the rim, it is desirable to construct the simplest slipway, which will enable you to centrovite these details.

If that wheel will seem unnecessarily complicated, you can make the design simpler: for example, two plywood discs connected along the periphery of the steel studs, and the center — grommet — cut steel pipe with welded thereto two flanges. Instead of ball bearings into the pipe, you can extrude a couple of plugs from the PCB or PTFE.

Pneumatics is desirable pressurewith to the rims a nylon rope with a diameter of about 10 mm. As a rule, this is done in two steps: first, the tires partially inflated, and then braid the rope and then pumped to finally.

The mast of a sailboat — thin-walled duralumin pipe with a diameter of about 50 mm and a length of 4265 mm. Install the mast for support, which form two

diamond-shaped gusset plate that is welded to the longeron. Fixing the mast on a sailboat is carried out with a forestay and two guys from steel cable. Stretch marks also enhance the frame of a sailboat. All these elements pull cable with screw turnbuckles (turnbuckles).

Sailing towing a skier:

I — the forestay (the wire 0 4), 2 the jib, 3 — wheel pneumatic, 4 — staysail-sheet, 5 blocks, 6 — stopper, 7 — spar frame, 8 — ghica-sheet, 9 — gik (duralumin tube diameter 3O), 10 — grotto, 11 — mast (aluminum tube diameter 50), 12 — a top weight, 13 — axis gimbal hinge (screws with nuts MB), 14 — universal joint, 15 — duck 16 — support crispity and masts, 17 — the gaff rig, 18 — cables (steel wire rope diameter 3), 19 —handle tug (steel pipe diameter of 30), 20 — axis (thin-wall steel pipe 0 50), 21, 28 — stretch (steel cable diameter 3), 22, 23 — axis crispity and mast (M8 screws and nuts), 24 — braid wheels, 25 — scarf 26 — crank (PCB), a 27 — diamond solitaire (sheet s2), 29 — screw the lanyards. (On the front and in the sail plan and running rigging conventionally not shown.)

Wheel-pneumatic:

1 — rim (steel pipe diameter 12), 2 — cross rim (6 PCs.), 3 — hub, 4 — spoke (12 PCs), 5 — pneumatic (truck or machinery), 6 — braid wheels (nylon rope diameter 10).

Wheel hub:

1 — ring 2 sleeve 3 bearing No. 204 (2 PCs.)

Staysail:

1 — palova plate, 2 — rear foot, 3 — Shkotovo angle with eyelet, 4 — bottom part, 5 — galbavy angle with eyelet, 6 — nylon rope 0 6, 7 — loop under the hooks, 8 — rifle, 9 — front foot.

For sails any sturdy fabric: pillow tick, Bologna, can be used and windproof synthetic fabric. In the end, for one season, it is possible to make a sail and made of polyethylene or Mylar film, sticking the cloth tape over it.

I think no need to describe the technology of making sails in the journal “modelist-Konstruktor” regularly appear on sailboats where such recommendations enough.

A few words about the sequence in which it is necessary to equip a sailing ship. As can be seen from the drawing, the grotto has two pockets under the mast and under the boom. First, loosen the cable lanyards and rasstegivat a mast with a hinge on the frame spar. On the mast pull the sail and re-fixed on the hinge. Then otstoyat boom, inserting it into the boom-pocket of the sail fastened to the mast. Then “stuffed” lanyards vant and stretched the sail with the help of kertikov, passed through the eyelets head points, the tack and sheet of the corners of the sail.

To set the staysail, in each of the loops, slotted along its luff point, is introduced carabiner — for “fastening” of the headsail to the forestay of a sailboat. The free ends of the rope are embedded in the forward leech of the sail, fixed to the forward end of the longeron and the top end of the mast.

Wiring of the Scots traditional for this kind of sailing. The jib sheets (a nylon rope with a diameter of 6…8 mm) grommet secured to the sheet angle and the sail is passed through the blocks on the spar frame and tubular stoppers. The geek sheet is passed through a few blocks (on the boom and the frame spar) and also fix the tubular stopper.

Technique sail the tug is almost the same as when driving a yacht, Dinghy or glider. Of course, there need to be a good skier and feel confident at any speed. In the event of critical situations immediately drop the control arm a tug. The sailboat in this case, as a rule, turns on the nose and stops. For walks on the tow choose open spaces — the frozen reservoirs or even fields. Please note that you are unlikely to be able to move through loose snow so the best time to ski in tow behind the sailboat is the beginning of winter or the end of it, when the snow formed a thick crust.

Use this sailboat can not only in winter. Mounted on the frame, use one wheel-pneumatic, you can easily turn the tug in the wheel of Buer that is able to move both on snow and on dirt roads, on asphalt and even on… the water. Wheels and Pneumatics it will withstand the weight of the structure, and the weight of the driver.

Igor KARAMYSHEV, design engineer

Recommend to read

THE TRUNK PLUS CASE
For the motorist the trunk of the car is not only convenience, but also a number of related problems. And first of all — observance of the required aerodynamics. The fact that in...
SHINE EVEN BLOWN
Inspired by the originality of technical solution, published in the journal "modelist-Konstruktor" No. 11'78, I modified the circuit for fluorescent lamps and for many years its use in...