“STAYERS” BLUE AQUADROME | MODEL CONSTRUCTION

We offer modelers design developed and successfully tested Czechoslovak athletes. The basis for its design was the model class F1E, with which the author is an engineer Ow. Valens was in the recent past, the champion of Czechoslovakia. New electrolyser, named “Mamba” (the African name of a small moving extremely poisonous snakes), helped Czechoslovak athlete to become a gold medalist of the national championship and in the class FSR. At the same VL. Valenta believes that despite the specialization of a new model for long races, it has preserved the “hereditary information” and can be successfully used in the RC electric class F1E. It is enough just to increase the number of batteries and to install a more powerful motor. Basically the same option (FSR) applied a set of twenty Nickel-cadmium batteries of the Japanese firm “Tamiya” and the engine the “Mabuchi 540”.

Celebarty case “train” is assembled from prepared elements on flat Board-the slipway the keel up. The Central part of the bottom plating outside after vyshkurivaetsya glued on liquid epoxy resin with a thin fiberglass with a specific weight of 110 r/m2, and the amount of binder should be minimized. The surface of the bottom should not be too smooth; after curing the resin impregnating the balsa outer skin plates, the structure of the fabric comes through clearly. So achieve turbulent flow around the bottom of the glider, which is important to achieve high speeds. The rest of the surface upholstered in long-fibre paper that strengthen the soft balsa surface and protects the wood from swelling.

The original longitudinal sponsons are mounted Reiki byshooting of solid wood of triangular cross-section, and on side cheeks — balsa rails with cross section 10 x 10 mm. the Latter act as reliable protection of the extremely lightweight of the hull when hitting fiberglass hard shell models of the rivals and additionally increases the effective width of the planing surface at low speeds.

The dimensions of the stern tube is not critical. You can use preset outer diameter 4-5 mm, and internal — from 3 to 3.5 mm. the Propeller shaft is made of high quality steel wire Ø 2 mm, if necessary, the workpiece is carefully aligned. With the propeller shaft end pesetas soldered adapter with external M4 thread. Despite the fact that the axis of the propeller shaft coincides with the axis of the armature of the motor, between them, necessarily introduced a small universal joint. In the stern tube shaft is mounted on two Teflon bushings-bearings. The cavity of the deadwood transmisiones is filled with oil to prevent water penetration inside the case.

The power batteries are divided into two prosekli that are placed on the bottom of the casing and displacement protection in a light foam blocks. For connections of power circuits (battery switch — engine) uses a flexible cable with a cross section of conductor not less than 2.5 mm² in secure isolation.

To control the model can fit any instrument with two steering servos. Receiver antenna is shortened to 100 mm, and its end is equipped with microstockers. The nest mate is worked on the case, as both holder steel whip antenna wire Ø 0,5 mm.

The propeller is selected depending on the running characteristics of the motor. For motor “Mabuchi 540”, powered by 10-15 Nickel-cadmium batteries, and conditions of a long race is well suited screw company “Graup-ner” type R35 or the other (as well as a homemade screw) Ø 35 mm and a pitch of about 30 mm.

RC sudomodel motor:

1 — Board servos (plywood 2 mm), 2 — bracket plates starting numbers (made of anodized aluminum 1 mm), 3 — deck (balsa 2mm), 4 — longitudinal bulkhead (balsa 2 mm, the dotted shading shows the circuit details) 5 — cover (plastic 0.3—0.5 mm), 6 — bow scarf (balsa 3 mm). 7 — lodgements (plywood 5 mm), 8 — universal joint, 9 — lateral part of the skin of the bottom (balsa 2mm), 10 — the middle part of the skin of the bottom (2 mm balsa and fiberglass), 4 — the Central bulkhead (balsa 2mm), 12 — stern tube (brass, steel Ø5 X 0.75), the 13 fairing of deadwood (plywood 2 mm), 14 — adapter (bronze), 15 — rudder (brass 1 mm), 16 — tube base stock (plywood 5 mm), 17 — insert (balsa 2mm), 18 — Board (balsa 2mm), 19 — tube water discharge of oblacenja (copper Ø4 X 0.5), 20 — tube water intake cooling (copper Ø4 X 0.5), 21 — Klondike support tube of the rudder stock (plywood 5 mm), 22 — zygomatic lining (balsa), 23 — plug the antenna 24, the longitudinal redan (birch, rake of 3 x 3 mm), 25 — tube, rudder (aluminum), 26 — horn of the rudder (aluminum).

Frames 1-5 are made of balsa 2 mm, a dashed line with asterisks is shown being removed after Assembly of the housing sections.

THE COMMENT OF THE EXPERT

The model of the champion of Czechoslovakia VL. Valenta is of interest by its simple design and original solved and easily reproducible contours planing surface of the bottom of the housing. To recommend the drawings of this model is possible first of all to the hobby of the middle class, for whom the repetition of the other extra devices or unbearable for reasons of unavailability of materials or because of the uniqueness used in their construction technologies.

Consider the option — not the only one. If the search balsa for the hull in the end proved fruitless, we recommend you to go for a slight increase in the mass of the body. This, however, will necessitate reducing the number of power accumulators, and as a result, the fall speed or time speed without changing the set power the motor. But in this case it would be possible to get all the balsa parts to replace… cardboard).

The reliability of the bonding such plastic parts is minimal, the weight them is beyond all conceivable limits. It is also necessary to clearly follow and recommendations on the finish lacquers. After inaccurate translation into foreign languages two-component parquet lacquer, with the properties similar to epoxy resin is almost completely impregnating the inside of the cardboard ready-made body, was… two layers of regular varnish blend on the outside! Returning to the name “cardboard”, we note that the only acceptable synonym — “presspan”.

If you do not take into account the race for claiming top results, you can go for the replacement of unit Nickel-cadmium batteries. Here the necessary experiments. I can only suggest the direction of the search: use to power the big round batteries-elements of type P20. Of all other common batteries these made initially only for the Chinese lanterns, have now become the best in the specific energy consumption. So, fresh batteries in a metal case having manufacturing capacity of 3.2— 3.5 A·h with a mass just over 100 g and the short-circuit current more than 10 A (the last number indicates a low internal resistance of the element).

V. ARTSEV, engineer

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