TRIMARAN: SPEED AND MANEUVER

Racing sudomodel motor. Racing RC miniature electric scooters have always been popular with modelers, especially among those who only starts to master these amazing racing cars. This to a large extent contribute to: the relative simplicity of the modern lines of gliders, making it possible to manufacture the housing from a variety of materials and to use the best available for model making technologies; the reliability of the electric power plant, excluding the start-up problems inherent in internal-combustion engines; and, finally, not too expensive – only two-channel – remote control equipment.

In our today’s post is a simple and very spectacular racing sudomodel-trimaran. We offer our readers one of the simplest hydroplane mixed design.

The Central body of the model consists of a rigid box with lines of type “sea sled”; frames made of plywood and the stringers and planking of pine slats. The housing has a removable cover consisting of longitudinal ribs, with cross members and plating. Fixation of the cover on the housing using screws with round knurled head.

Frames divide the housing into three compartments: the forward (propulsion), Central (the battery) and feed (control). In the forward to an enhanced frame of 5 mm plywood fixed engine Speed 600 Graupner company, resulting in the rotation of a three-bladed propeller with a diameter of 35 mm and 47 mm. step of Change of frequency of rotation of the shaft driving motor is produced by the speed controller of remote control equipment. In the Central compartment is the battery, consisting of seven Nickel-cadmium elements with a total capacity of 1.2 Ah and a voltage of 8.4 V. In the aft compartment fixed receiver two-channel proportional equipment and servo system remote control. The last is offset to the left from the plane of symmetry of the model at 20 mm.

Geometry RC racing boat
 

The most common variant of the race track (the numbers show the sequence of the route)

Floats glider also collected from plywood frames, glued it to the stringers of pine slats 4×4 mm and plating. In addition, for the plating used 1 mm plywood for the frames made of 3-mm plywood. The Assembly epoxy resin.

Dock floats with the body is carried out using double beam bridge consisting of a pair of beech wedges. After Assembly the space between the Central hull and the floats filled with lime, or, what is better with balsa.

The finished hull and the floats using epoxy resin pasted a layer of thin fiberglass. Next — Vykurovanie surfaces and paint topcoats.

The engine is mated with the propeller shaft with universal joints consisting of two aluminum half-couplings and hinged to them two steel pins elastic rubber biscuit. Deadwood is a dural tube with an outer diameter of 10 mm, the ends of which are inserted PTFE (can be printed) sleeve. During the installation of this node in the case of the model, the deadwood is filled with grease. The propeller is made of brass — blades propeller fixed in chiseled the sleeve by means of soldering, propeller shaft screw fixed cylindrical pin.

Layout size:

1 – nasal boss (Linden); 2 — deck (plywood s1); 3 — cockpit cover (plywood s2); 4,26 — beam bridge (beech); 5 — jointed coupling; 6 — shell of light (Vileika of fiberglass and epoxy binder; 7— Nickel-cadmium batteries; 8— frame № 2 (plywood s3); 9 receiver remote control equipment; 10—steering washer; 11 – the steering mount bracket (M4 bolt with nut and washer); 12— tie-rod (wire OVS d2); 13 — steering bracket; 14—the guy (rubber thread); 15 — shaft; 16 steering pen (plywood s4); 17 propeller d35, h = 47); 18 — deadwood; 19 — transom (plywood s5); 20 — stern shaft; 21 — hull bottom (plywood s1); 22 — stringer (pine, rail 4×4); 23 frame No. 1 (plywood s5); 24— way motor (Speed 600 Graupner company); 25—lateral float; 27 — the bottom of the control compartment (plywood s4); 28 — the bottom battery cover (plywood s4)
 

Device drive propeller:

1 — stoppers (M3 screws); 2 — pin (cylindrical pins d2); 3,11—half coupling (aluminum); 4 — stern tube shaft (steel, d5); 5 —bushing deadwood (Teflon or textolite); 6— propeller (d35, h=47); 7 — fastening screw (cylinder pin d2); 8 — washer; 9 — deadwood (made of anodized aluminum, pipe d10x1); 10 — cross joint (elastomer); 12 — electric motor shaft

Steering the glider:

1 — steering bracket (made of anodized aluminum, the sheet s2,5); 2 — quickdraw (rubber thread a cross section of 2×2); 3 — steering pen (plywood s4); 4— axis steering pen (M4 screw with nut); 5 — shaft (duralumin, sheet s2,5): 6 — the axis of rotation of the shaft (bolt with nut M4); 7—tie rod (steel, wire EOD d2)

The steering device is a bracket bent from sheet aluminum with a thickness of 2.5 mm. of the same material and made the shaft — bracket it is hung with bolt and nut M4. To prevent the loosening nut contra nitro. The steering is feather cut from 4 mm plywood and has a symmetrical wing profile. The shaft it is fixed the hinge using M4 bolt, nut and two Teflon bushings. Upright steering pen is held with a rubber thread.

Adjustment of the glider is reduced to loading the hull with ballast for selection of an optimum position of the centre of gravity. Correctly balanced model easily goes on plane, nice and clearly describes circulation.

I. TEREKHOV