HEAVYWEIGHTS BLUE TRACKS

Categories World of models

POWERHOUSES OF THE BLUE TRACKSToday, we first introduce you to the most massive representatives of the ship-class F1-V. This high-speed RC ships with engines working volume of 10 to 15 cm3. One of the most successful developments in this subclass is the model A. Baidebekova.

The casing is assembled from two blanks, the lower (“bottom”) and top (“deck”). Each of them is formed in its matrix. Before starting work, the form is coated with a thin even layer of release compound (soap, “Edelvays”, shaving cream “florena” or “Le Corsaire”), then in the holes under the sponsons put the harnesses from fiberglass and epoxy resin, and the entire working surface of the matrix covered with two layers of fiberglass with a thickness of 0.1 and 0.3 mm. the Fabric should be saturated with resin, is introduced at the rate of 1 : 1 by weight glass fiber. After that is pre-customized foam “layer” of PVC-1 thickness 3.5—4 mm, and on top of it — another layer of glass, of a thickness of 0.3 mm.

 
The matrix with the “filling” is placed in a sealed plastic bag, from which pumped the air. In the vacuum Vileika aged 6-8 hours to cure the binder. To extract the finished part from the die is possible not earlier than in a day.
 
To reinforce puff design and improving the connection between the bearing shells is useful even before laying the foam layer to carry the sheets of foam holes Ø 1 mm at a distance of 30-40 mm from each other. When forming in a vacuum, they are filled with resin, thus increasing the reliability of the clutch all the layers of glass and interlayers.
 
The upper part of the body is the same. The only difference is that all three layer fiberglass here are the same thickness — 0.1 mm, and epoxy they injected a little more, at the rate of 1.2 weight parts of resin 1, the weight of the fabric.
R / C model class F1-V15.
RC model class F1-V15:
1 — intake, 2 — the front frame, 3 — carb engine, 4 — engine, 5 — shaft, 6 — deadwood 7 — and the rear bulkhead, 8 — channel, under the silencer, 9 — thruster, 10 — wheel, 11 — resonant silencer, 12 — latch 13 — motor, 14 — “guided needle” nozzle, 15 — a longitudinal partition, a 16 — engine compartment lid, 17 — fuel tank 18 — antenna; 19 — a cover of the instrumental compartment, 20 — bracket.
 
Before removing the bottoms from the matrix in it stuck to the transom of fiberglass 1.5 mm thickness transverse frames and longitudinal bulkhead, made in the form of a layer of panels such as fiberglass — foam — fiberglass or fiberglass — foam. The transom and rear bulkhead must be prepared holes for sealing fiberglass tube channel under the resonant silencer.
 
The engine compartment cover cut out vyklicky case and hung on the hinges in closed position it is fixed with a latch. Cover of the instrumental compartment of a sheet of Plexiglas with a thickness of 3-4 mm, the shell is attached by six M3 screws with seal the seam with a strip of porous rubber with a thickness of 2-3 mm.
 
An antenna for receiving signals from the transmitter serves as a copper wire, Ø 0.25 mm, to one end of which is soldered flexible stranded wire with a length of 100-150 mm. the Antenna is glued along the length of the deck even when forming the part between the first and second layers of fiberglass so that vyklicky-level hardware compartment out of a stranded conductor. Antenna, place spikes and a small piece of wire needs to be formed inside the deck. At the end of cable mounted connector to mate with the receiver. This design of the horizontal antenna was first tested in 1981 and operated continuously since 1982. Her equipment is very reliable even at distances of 3-4 times the radius of the model; failure of equipment associated with the antenna part, were not observed. Instead of copper wire is acceptable to use a strip of copper or aluminum foil width of about 3 mm, glued along the side. With the introduction in the model design of carbon fabric application of such antennas is undesirable.
 
On models equipped with the engine working volume of 10.5 cm3 with water cooling. Motor mount from mild steel sheet of thickness 3mm is hinged on the housing by means of rubber shock absorbers. The shaft rotation is transmitted through cardan. Propeller shaft — alloy steel rod Ø 4 mm — passes the stern tube stainless steel tube Ø 7X0,5 mm. Deadwood carries three bearing bushings. The lower is machined from bronze, and middle and upper — made of PTFE. Application average additional sleeve significantly reduces the amplitude of elastic oscillations of the shaft and does not allow it to touch the walls of the stern tube.
 
Propeller Ø 53 mm has a step 68 mm. Blades of stainless steel are sealed with solder RPS-45 in the hub made of brass LS-59. The grooves for the blades are milled on the machine.
 
Additional removable stub resonant silencer.
Additional removable stub resonance of the muffler:
1 — tubular divider (steel, tube Ø 4,5X0,25 mm), 2 — bulkhead (steel, diameter 30 mm drilling 8 holes Ø 4.5 mm uniformly around the circumference), 3 — the output cone (stainless steel of thickness 0.2 mm); three holes M3 to run in conjunction with a silencer.
 
Projection
The projection of “housing”.
The numbering of the sections corresponds to the General form of the model.
 
The resonant silencer can be fixed using the bracket and rubber damper installed on the transom. The walls of the muffler separated from the walls of fiberglass channel a ring of heat resistant rubber. In the upper part between the ring and the silencer left clearance for the exit of cooling air. The front part of the muffler carries a telescopic joint through which it is possible to change the length of the resonant part of the system, reduce noise, i.e. to set its engine speed.
 
Fuel tank — a plastic bottle of shampoo with a volume of 200 cm3. The technology of manufacturing such a tank was given in the “M-K” № 6, 1983. Through the transparent walls it is convenient to assess the condition and determine the level of the fuel mixture.
The control of the engine speed is performed through two channels: the air choke carb and needle jet. The first provides a rough, and the second fine adjustment of the composition of the fuel-air mixture.
 
It should be noted that models in this subclass have the most powerful, and hence very noisy engines. Why the fight against noise, which should not exceed 80 dB, one of the main design problems. The proposed RC will apply the following measures:
 
enclosures, frames and longitudinal bulkhead is made in the form of layered panels that act as sound insulators;
 
— the engine and the damping system are completely hidden in the volume of the housing;
 
— the engine and muffler are attached to the model using the rubber components and shock absorbers;
 
— used engine with reduced cubic capacity;
 
— applied additional special plug in the muffler;
 
— in deadwood is installed intermediate the sleeve of PTFE, which reduces vibrations and noise of the propeller shaft.
 
As a result, all the control starts the competition 1986, the actual noise does not exceed 79-80 dB.
 
It is necessary to highlight some of the features of the geometry of the hull form. The bottom is provided with a narrow longitudinal planing steps, their width does not exceed 7 mm. This solution allows to reduce the flow resistance without making the body of excessive lift force, which affects the stability. One of the important characteristics is the deadrise at the transom. In this case, its value is 13°. By increasing the deadrise of more than 15° starts swinging going vessel around its longitudinal axis and decreases the resistance roll. And decreasing below 10° due to the small internal roll on turns centrifugal force can tilt the model to the outside, which was observed on some early designs. When the big twist of the bottom (low deadrise at the transom and a big nose) RC bad out of the turn, continuing the circulation after bringing the helm in neutral.
 
It should be noted that most associated with the instability of the motion of the model problem disappears if to install instead of a hard propeller shaft flexible, and so that the axis of rotation of the screw is parallel to the longitudinal axis of the body. However, such a transfer more complex and less reliable, its use is expedient only in the case when there are no more simple methods of solving the sustainability issues.
 
The mass of the proposed model with an empty tank — 3.0 kg. It can be operated not only with engines of foreign production, but with mass domestic. So, control starts in the summer of 1986 with an engine MDS-10 KU working volume of 10 cm3 was achieved the result is 14.9, which is more than a second higher than the standard of master of sports of the USSR in this class.
 
A. BITERYAKOV

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