Models of gliders taking off from a catapult are some of the most uncomplicated and entertaining models. They are great in the air. They are easy to give a modern shape and attractive appearance. But the main advantage of such models is their "clean" and rapid flight, the ability to make aerobatic maneuvers.
It is no wonder that miniature aircraft of a similar class are very attractive to aircraft modellers, especially beginners.
When designing such a model of a glider, one should not forget that it should, perhaps, be lighter. And its center of gravity is to coincide with the leading edge of the wing (with a rectangular wing) or with the forehead of the average aerodynamic chord (with a swept wing). Regardless of its relative simplicity, the glider model must have very ideal aerodynamics - only in this case it will demonstrate excellent results in terms of clean execution and duration of aerobatics.
So, in the manufacture it is very necessary to equip it with a wing with a plano-convex profile, and not with a plywood plate with slightly rounded leading and trailing edges. Finishing also has a great influence on the level of flight quality: meticulously assembled and polished models fly better. When choosing an aerodynamic configuration, it should be taken into account that swept-wing models are more stable in flight and the stabilizer cannot be set at a huge negative angle. We offer three ejection glider models
The first model of a glider - a high-wing aircraft - is made entirely of light pine. To begin with, a rectangular bar of 35 × 20 mm is selected or planed. It marks the outline of the fuselage in side view, the placement and shape of the slots under the wing, fin and stabilizer. Then the workpiece is cut, the contour of the fuselage is marked in plan and this element of the model is completely processed.
The wing, stabilizer and keel of the glider are cut from pine planks.
The large thickness of the wing at the side of the fuselage - 5 mm, at the tip - 3 mm. The profile is plano-convex, with a large thickness located at a distance of 1/3 of the chord from the wing tip. In the manufacture of scrupulously look for the symmetry of the right and left halves by means of simple patterns of narrow plywood.
The same attention is paid to the manufacture of the keel and stabilizer. The finished wing, fin and stabilizer are glued into the fuselage slots.
The wing is additionally fixed with carnations. If gaps form during installation, they are filled with pieces of wood, fixed with glue. At the end of the drying of the glue, the symmetry of the right and left halves of the wing is once again controlled, and the model is scrupulously sanded. Then a starting hook made of metal wire or a light nail is attached to the fuselage and centered without a motor.
As already mentioned, its center of gravity must coincide with the forehead of the average aerodynamic chord (for a high-wing plane, the distance from its plane of symmetry to the average aerodynamic chord is about 70 mm).
If the schnobel of the model is too light, it is loaded with pieces of lead. At the time when equilibrium is obtained, the pieces are removed, melted and poured into lead into a hole drilled in the nose. At the end, the airframe model is primed, sanded again and painted with nitro enamel: the upper part is red, the lower part is light blue.
The second model of steam glider is different from the first one. In particular, it is with a mid-wing. The development of its manufacture is actually the same.
The only difference is the wing embedded in the fuselage. The glider is painted with “silver”, the keel and cockpit are decorated with blue paint, the stars and numbers are “stuffed” with red nitro enamel using stencils. Final finishing - besides this parquet lacquer.
The medium plan is very successful in design and, with the right adjustment, easily makes two Nesterov loops one after the other. The mass of the finished model is approximately 50 g.
The third glider differs from the previous ones for the most part in that its wing, stabilizer and keel are made of plywood. The wing has a zero setting angle; at the stabilizer - negative: 2-3 °. Requires very good adjustment. Particular attention must be paid to the elimination of distortions of the wing and stabilizer.
A meticulously adjusted model at a tremendous speed makes flights of extraordinary beauty.
The aircraft is painted with white or aluminum paint, the rudders and cockpit are light blue, and the stars and trim tabs are red. The pictures show a variant of applying “seams” between the skin pages, which can be depicted with liquid dark nitro enamel or dark ink using a drawing pen. Indeed, at the end of the ink, the model must be covered with one layer of parquet varnish.
model launch and glider catapult device
The catapult is made of 15 strands of model aircraft rubber woven into a braid. Iron rings are threaded into the loops at the ends of the rubber cord. The non-specialized length of the cord is 1.5 m. In addition, a special peg is included in the catapult, in the upper part of which a hook is attached under the ring of the rubber cord.
At the time of launch, there should be no one in the forefront in the 90-degree sector. First, test (adjustment) flights are created with a weak tension of the rubber cord. If the model falls on the wing, then this, in most cases, is due to a skew of the wing or keel.
The disadvantage is corrected by bending the wing or keel in the direction opposite to the stall. If the model makes ascending “barrels”, then the back of the stabilizer is deflected down or the schnobel is loaded.
Having achieved a stable flight, the mini-plane is launched with the full tension of the rubber cord of the catapult. A perfectly adjusted model makes a Nesterov loop at an enormous speed, makes a hill and, turning around, glides steadily. From time to time, it leaves the loop directly above the launch site or, moreover, behind the launcher, therefore, during launches, it is necessary to look very closely at the flight path.
Otherwise, the high-speed model can cause an important injury to the athlete.
(Creator: I.KARAMYSHEV)
What boy does not admire such constructions as airplanes? Do-it-yourself aircraft models made from ceiling tiles are a great gift for children who are fond of aviation. Especially if they took part in the assembly of the airframe. The article will tell you how to make a simple airplane model from ceiling tiles.
Aircraft model building is a popular technical sport that is of interest to schoolchildren, students, workers and engineers. At the same time, everyone chooses for himself a class of aircraft models that meets his interests.
In aircraft modeling, three rather large groups of aircraft models are distinguished, presented in the table:
| Model class | Peculiarities |
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In such models, the intervention of the designer is impossible during the flight. All adjustments and settings of the aircraft are completed when it is launched. They can be: - non-motorized - gliders; - with the simplest, very small, internal combustion engine, which is attached to the body with an elastic band. The motors on the models work for several seconds to throw the light-winged structures up to a hundred meters up, and then they smoothly descend. Timers or special clock mechanisms are used to turn off the engine and transfer the steering wheel to planning. |
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With such models, the athlete controls wire threads, which are called cords. The vehicles fly in a circle with a diameter of about 40 meters. The “pilot” is located in its center with a control stick. When the handle is pulled towards you, the elevator is deflected, and the device obediently flies up. And the deviation of the handle from itself causes the model to decrease. The devices are:
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Controlled remotely, without wires. To do this, there is a set of radio equipment, which includes a transmitter, in the hands of the operator, and a receiver with steering mechanisms mounted on board the model. |
Tip: Before you make an airplane out of ceiling tiles, you need to get acquainted with its design.
The device of all models is very similar. The main components of the radio-controlled aircraft model are shown in the photo.
It:
Installed inside:
A rudder is mounted on the rear end of the keel.
Tip: If there is no landing gear, the model should be started from the hands, and the aircraft should be landed “on its belly”.
Tip: When choosing to make an airplane from ceiling tiles with your own hands, it is necessary to ensure, first of all, the reliability of taking off and landing, and then satisfying aesthetic needs.
The aircraft model must have the following properties:
For work you will need tools and materials:
Making any design, including an aircraft model, with your own hands begins with the development of drawings. To do this, you can use the services of specialists or copy them from sites by printing templates on a printer or drawing to size.
After printer:
From the ceiling tiles, according to the prepared templates, blanks are cut out for assembling the aircraft.
Tip: To prevent the sheets from moving off the tile, they must be fixed to the surface of the material with glue. After marking is completed, the glue does not have time to dry and the paper is easily removed without damage for further use.
Before proceeding with the assembly of all the parts, it is better to watch the video.
The aircraft assembly technology can be roughly described as follows:
Tip: Titanium glue should be used for work, its price is the most affordable for beginner modellers. It is more convenient to apply glue with a syringe without a needle, using it as a dispenser.
Car modeling, motor glider, foam planes. Motor installation
Assembling airplanes from ceiling tiles is the easiest option that a novice aviation enthusiast can do if desired. The main condition is to do everything carefully, adhering to the assembly technology, but it is better to take the advice of a specialist.
This simple mechanical toy will give a lot of fun to young knights besieging impregnable fortresses.
Catapult- This is a medieval siege weapon designed to throw huge stones and other heavy projectiles at enemy fortifications. With the help of a long lever driven by a counterweight, she could throw objects weighing up to 150 kg over a distance of several hundred meters at high speed. The projectile was placed in a sling stretched along the platform. When fired, a long lever, along with a tied sling, quickly rose vertically and one of the ends of the sling was released, allowing the projectile to fly towards the target.
1. From a maple board 6 mm thick, cut out the sides BUT and platform AT according to the dimensions indicated in the "List of Materials". Place the platform on 3 mm thick pads and glue the sides to its edges, aligning the ends of the parts (Fig. 1 and 1a). Make sure the gluing is square and fix the parts with clamps.
2. From the material 13 mm thick, cut out the support bars FROM. Install a 6 mm thick slotted disc in the saw. Using a corner (cross) stop with a wooden lining and a stopper, cut out grooves in the support bars 3 mm deep at a distance of 25 mm from the ends (Fig. 1), turning the parts 180° after each pass.
Brief advice! Check the settings on a trial cut. With two passes with a turn of the part, even a small inaccuracy is doubled, and the required distance between the grooves cannot be obtained. Make test passes on a cut of the same length and adjust the settings if necessary.
Glue, fixing with clamps, the support bars C to the sides of the platform A. Position the outer bars as shown in the photo, and the inner ones at a distance of 51 mm from them.
Lubricate the grooves with glue and glue the bars to the sides of the platform (Fig. 1 and photo A).
1. From the material with a thickness of 13 mm, cut out the racks D. Using a router table, chamfer 3 mm wide along the outer edges, as well as along the ends of each rack (Fig. 1). Drill through holes with a diameter of 5 mm for the brass rod in the indicated places.
2. Make four copies of the brace pattern E. Cut blanks for struts from a 6 mm thick board and attach templates to them using spray glue. Using a jigsaw or bandsaw, cut out the pieces and sand them down to the contour line. Remove templates with a cloth soaked in solvent.
3. Apply glue to the long edge of the two struts E. Glue them to the rack D, aligning flush with the bottom end and the inside face (no chamfers). Glue the second pair of struts to another rack.
Glue the assembled strut struts to the sides of platform A, connecting them with a brass rod and aligning them in the middle above the middle support bars C.
4. For fastening finished racks D/E to the assembled platform A/B/C take a 5mm thick brass rod and saw off a 108mm piece that will help align the uprights. Apply a bead of adhesive along the bottom edge of each strut and strut assembly from the inside. Insert a brass rod into the holes in the uprights (photo B). Glue the strut struts to the sides of the platform, centering them over the pair of middle legs. FROM. When the glue dries, remove the brass rod.
1. Cut out the blank for the lever F. Make a copy of the lever template and use spray adhesive to attach it to the workpiece. Saw out the lever and sand to the contour line. Delete the template.
Note. Drill the through hole shown on the template with a diameter of 5 mm after gluing the overlays.G.
2. From 19 mm thick material, cut out a 35 × 305 mm blank for overlays G. Make two copies of the overlay template and attach them to the blank using spray adhesive. Saw out the overlays and sand them along the contour.
3. Using a drilling machine, drill into the edges of the trims G holes with a diameter of 3 and 5 mm in the places indicated on the template.
Clamping the part in a wooden hand vise, mill 3 mm wide chamfers on the overlays G in the places indicated on the template.
Brief advice! DCarefully drilling 5 mm holes is required to accurately align the parts and the brass rod. To center the hole in hard maple wood exactly where you want it, use a center point bit instead of a regular twist drill. And to keep the holes aligned, make sure the drill table is set at exactly 90° to the drilling axis.
Now chamfer 3 mm wide along the specified edges and ends of the overlays on both sides (photo C). Delete templates. To securely machine these small parts, hold them with a wooden hand vise and minimize clearance around the cutter by inserting an appropriately sized replacement ring into the mounting plate. If your router table doesn't have this option, use the Wizard's Tip below for a simple alternative.
No plate with interchangeable rings? Use an overlay!
There is a simple and quick way to make such an overlay. It will close the gap around the cutter, becoming a gap-free insert, and provide reliable support for small parts, allowing them to be processed safely. At the same time, it will cost you quite inexpensively - for its manufacture you only need a piece of hardboard.
4. Places for gluing overlays G marked on the lever template F. Glue one pad to the lever and fix it with a clamp. When the glue is dry, drill a 5 mm hole in the lever for the brass rod. (a photo D). Then glue the second pad to the lever, aligning the holes with a brass rod (photo E).
(Photo D) After gluing one of the pads G to the boom arm F, drill a 5 mm hole in the arm through the hole in the pad. (Photo E) Glue the second trim G on the other side, aligning it with a brass rod inserted into the axle hole.
1. Saw out side panels from a 6 mm thick board. H as well as front and rear I walls and bottom J. Cut out one more bottom piece to use as a spacer when assembling the drawer. Mark, file and sand the corner bevels on the side walls H (Fig. 2). Now assemble the box (photo F and G).
(Photo F) Apply glue to the end edges of the bottom J. Clamp the front and back walls of I against them, inserting a leveling spacer between them. (Photo G) Now apply glue to the edges of the bottom, back and front walls of the I/J. Press the side walls H against them with clamps.
2. Mill on the outside of the side walls H chamfers 3 mm wide (Fig. 2).
3. From the material with a thickness of 13 mm, cut out the lining To and drill through holes with a diameter of 6 mm in them using a drill with a central point. Then make corner bevels 6 mm wide. Due to their small size, sand these parts by hand using a sanding pad and #100 sandpaper.
4. Glue the overlays To to the side walls H, aligning them in the center with an indent of 13 mm from above, and fix them with clamps.
1. Drill in the lever F pilot hole 1.5×6 mm for ring head screw (Fig. 3). Then drill a 1.5x10mm hole in the top end of the arm for a 16mm hook rod. Screw a screw with a ring and a hook into the holes, leaving a protrusion of 6 mm.
2. To make a sling, take two pieces of cord 220 mm long and a piece of durable fabric or suede measuring 25 × 90 mm. Using an awl, make holes at the ends of the material in the indicated places. Tie the end of one piece of cord to the hole in the sling, and the other end to the screw ring at the end of the lever. Then tie a washer with a diameter of 6 mm to one end of the second segment, and also tie the remaining end to the free hole of the sling.
3. Before installing the arm with pads F/G between posts D screw 5x20 countersunk head screws into the 3mm holes in the escutcheons G to a depth of about 13 mm (Fig. 1). Then insert the assembled node F/G between the posts, passing a brass rod-axle with a diameter of 5 mm through the hole and adding 6 mm washers between the linings G and racks D.
4. For hanging the counterweight box H/I/J/K fasten on both pads To eye bolts with a diameter of 6 mm using M6 nuts without tightening them (Fig. 1). Then slide the eyebolt rings onto the screws in the boom arm pads and tighten the fasteners. (photo H and I).
(Photo H) Fit the eyebolts onto the screws in the caps G. Secure the eyebolts with the nuts. (Photo I) Drive the screws deeper into the G plates to secure the eyebolts securely. The counterweight, however, should swing easily.
5. Finally sand all parts of the catapult with sandpaper up to 220 grit and apply a top coat of your choice. Can't wait to test the throwing machine in action? Read the "How the Catapult Shoots" box for tips on how to use this toy effectively and safely. Now it's time to declare war on the enemy!
Its principle of operation is the same as that of the giant fighting machines of the Middle Ages, but this small model is designed as a means of entertainment and is designed to throw small objects, such as unshelled hazelnuts or sweets, to accurately hit a box, basket or other target. For your safety, and to ensure that you get the most out of your catapult, follow these tips.
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In this article, Bob, the author of the YouTube channel "I Like To Make Stuff" will tell you about his rather daring and unusual catapult project.
Materials.
- Pine board 50x100 mm
- Silicone hose
- Plastic ties
- Perforated steel strip
- Aluminum profile
- Steel stud, nuts
- Wood screws.
Tools used by the author.
- Clamps
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- Miter saw
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- Square, pencil, tape measure
Manufacturing process.
First of all, the author cuts the material, bars 50x100 mm in size, and proceeds to the construction of the frame.
Several bars are cut in half in order to make racks and several diagonals out of them.
Excess hairpins are cut off with a grinder. Now the rod is fixed in both parts with nuts.
The transverse partition had to be removed, it interferes with the full stroke of the boom.
The screws at this point must be long enough to withstand the force that the lever will create.
Throwing model-half-copy of the Su-24 aircraft. The model was designed and manufactured in the aircraft modeling laboratory of the Center for Children's and Youth Technical Creativity in Rybinsk for beginner aircraft modellers. The prototype was a modern supersonic bomber with a variable geometry (swept) wing Su-24, which is in service with the Russian Air Force. The launches of such models always arouse interest among both the club members and the audience. And due to the ease of manufacture, the model of this jet aircraft enjoyed great success in suburban children's centers.
Materials for a semi-copy will need the most affordable: PS-4-40 foam sheet (300x210x3 mm), 3 mm plywood for the spout, aircraft model rubber and PVA glue. And from the tools you only need a scalpel, marker, pencil, ruler, scissors and pins.
Model making. Most of the details are cut out of foam. Only the nose is made of plywood. It is best to process the foam plastic with a thermal cutter, the cutting element of which is a nichrome wire heated by an electric current.
It is most convenient for novice modellers to mark the contours of parts according to pre-made templates made of thick cardboard, but older guys can use the method of transferring the configuration of parts from a drawing to foam and plywood using carbon paper. So that the drawing does not deteriorate, it makes sense to protect it with plastic wrap.
The production of the model begins with the marking on a 3 mm foam sheet with dimensions of 300 × 210 mm of the contours of the model details. This work should be carried out with maximum accuracy - the flight qualities of a semi-copy depend on this. The bow is marked on a sheet of 3 mm plywood. It should be noted that the model requires a double set of wing panels and fuselage sidewalls and six sets of weapon suspension pylons.
1 - wing consoles; 2 - fuselage sidewalls; 3 - upper part of the fuselage; 4 - the lower part of the fuselage; 5- halves of the stabilizer; 6- keel; 7 - partition; 8- fairing; 9 - forward fuselage; 10 - armament suspension pylons (6 pcs.)
Main details of the model(numbering of parts corresponds to the positions of the assembly diagram)
The next operation is cutting with a sharp scalpel along the marking of all foam parts. In this case, it is desirable to use a metal ruler. For novice modellers, this operation is best done with scissors. The ends of the cut parts must be leveled with sandpaper.
The most complex and time-consuming part of the model is the nose: it is cut out of 3 mm plywood with a jigsaw and processed with a file and sandpaper. The groove for hooking the rubber of the model launch catapult should not have sharp edges, otherwise the rubber on them will quickly fray.
The assembly of the foam parts is carried out on PVA glue, using ordinary tailor's pins to temporarily fix the parts relative to each other. This is how the stabilizer is first glued to the top of the fuselage. If the glue is thick, then before work it should be slightly diluted with water to better coat the surfaces.
The sides and upper parts of the engine nacelles are connected with pins, after which the joints are smeared with glue from the inside. At the end., The lower parts of the engine nacelles are glued, and they are glued between the sidewalls with their fixation between them with pins.
Next, you need to select the required sweep of the rotary (on the prototype) wing consoles and glue them to the center section by inserting their root parts into the slots in the fuselage sidewalls, and then glue the jumper into the middle of the rear fuselage.
After the final drying of the glue, the technological pins that fixed the parts to be glued are removed, and the nose element of the model is joined to the fuselage box and the joints are carefully coated from the inside with PVA glue.
In the rear part of the fuselage, the keel is glued with temporary fixation with the same pins. On top of the fuselage of the model, a fairing is glued, also cut out of a foam strip. After the glue has dried, weapon suspension pylons are installed in their places in accordance with the assembly diagram of the model.
Model finishing. As already mentioned, the throwable model is a copy of a modern supersonic bomber, so it is desirable to paint it in accordance with the color of the prototype aircraft. We recommend using indelible markers for this, with which you can draw the contours of ailerons, flaps, rudder, technological joints, air intakes, as well as stars and side numbers.
For more copies, you can paint the model with light blue nitro enamel with an airbrush. It is best to do this in a specially ventilated room or outdoors, away from fire. When using an airbrush filled with nitro enamel, it is recommended to keep it at a distance of 150-200 mm from the model in order to prevent the foam from dissolving; In this case, the paint should be diluted only with acetone.
Model balancing. On the assembly diagram of the semi-copy, the position of its center of gravity (CG) is indicated, which guarantees a stable flight of the model with a sweep of the wing panels of 35 °. When the sweep changes up or down, the centering is selected experimentally using plasticine added to the nose or tail of the aircraft.
Adjustment and launch of the model. Before launching from a catapult, the model should be adjusted in gliding test flights by hand. If the model glides steadily and the flight range is 10-15 m, then it can be launched from a catapult. The catapult is a ring of rubber thread with a section of 2×1 and a length of 400 mm. After tying the ring, pinch the knot with your fingers. With the other hand, take the tail of the model and, pulling it away, release it. If the model is well assembled, then immediately after a successful launch, it should make either a Nesterov loop or an “immelmann-half-pin” and land spectacularly.
Possible disadvantages of planning are eliminated by bending the trailing edges of the keel and stabilizer. By changing the sweep of the wing and the angles of deviation of the edges of the tail, you can make the model perform aerobatics - such as "barrel", "loop", "immelman", "bell" and others.
A - when diving, the trailing edges of the stabilizer blades are bent up; B - when pitching, the trailing edges of the stabilizer blades are bent down; B - bending down the trailing edge of the wing of the left console will help get rid of the left roll; D - in normal flight, the model glides steadily at a distance of 10-15 m; D - the adjusted model is launched using a rubber thread catapult
Based on the Su-24 model, our laboratory developed and manufactured propelling semi-copies of the MiG-29, Su-27, MiG-25, R-18 and R-16 aircraft. All of them have different sizes and weights, but they are united by spectacular flight, attractive appearance and ease of manufacture.
To develop the design abilities of novice modellers, on the basis of these models, it is possible to develop experimental copies of various schemes: tailless, flying wing, duck and others.
In competitions of modellers with semi-copies, copies, flight time, cleanliness of aerobatics and originality of design (for experimental models) are evaluated.
In conclusion, it should be noted that larger models can also be made, increasing the linear dimensions by one and a half times. In this case, you can use 5-mm plates prepared with a thermal cutter from quite affordable packaging foam.
Technical data of the Su-24 semi-copy model
Wingspan, mm;
at a sweep angle of 15° …. 280
at a sweep angle of 68°….. 210
at a sweep angle of 35°….. 260
Length, mm………………………………. 285
Height, mm…………………………….. 80
Model weight, g……………………… 20
S. KOLONSKOV, teacher of additional education of the highest category, Central Children's and Youth Sports School, Rybinsk
