7. HOW TO MAKE MODEL ROCKETS
Read all the instructions in this chapter carefully before picking out the model you would like to make first.
Select some out-of-the-way place to work. If you do not have a workbench of your own, the top of a table will do, but be sure your parents do not mind your using it. It will be helpful to have two boxes, one in which to keep the materials for your rockets and the other for your tools.
When you have finished reading this chapter, decide which rocket you would like to make to start. Each rocket is a simplified model reduced to approximate scale. If you want all your models to be in the same scale, you will have to enlarge some of the patterns. Instructions for doing this are given at the end of the chapter. Enlarge the patterns for the CH-IO, the T-2, and the Saturn to twice the size they are in the book, and the Nova patterns to three times the size. In enlarging the dowel parts for these models increase the length only. It is not necessary to get thicker dowel.
You will have to reduce the size of the patterns for the Project Mercury capsule to one half their size. To reduce these patterns, reverse the procedure for enlarging.
There are three pages of illustrations for each rocket except the Saturn and the Nova, for which there are four. The first is a perspective drawing to show you how the model will look when it is finished. This will help you to shape the parts and cement them together. Next, there is a page of patterns to show you the outline of the parts (note that there are two pages of patterns for the Saturn and the Nova). Finally, there is a page of plans which shows three views of the rockets—a side, a top-end, and a bottom-end view, or sometimes another view that will be more helpful. These drawings show the relative positions of the parts to help you to cement them together correctly.
To help you to identify the parts, each particular one is identified by the same letter in all the drawings. For instance, B is always the body, N is always the nose, E is always the engine, and so on.
The first part of your model to make is the body. You can use a cardboard tube if you have one that is the correct size. Check the size by matching it against the pattern. Be sure it is the correct diameter and length. The bodies of the smaller models are made with wooden dowels.
If you do not have a ready-made tube to use for the body, you can make it with ¼-inch dowel, some pieces of heavy cardboard, and heavy paper. To make it easier to follow these instructions for constructing the body, refer to the Atlas patterns on page 43. First, cut out circles of light cardboard for the round discs (D and D in the part labeled B for body). Use a pencil compass to mark off the discs on the cardboard, copying the patterns for them. Cement two or three circles of cardboard together to make the discs strong (Diagram 1). Hold the pieces tightly together until the cement sets. Next, saw a piece of ¼-inch, dowel to the correct length of the core (S) and sandpaper the ends on a sandpaper block, using a circular motion, to make them flat and even (Diagram 2).
To make a sandpaper block, saw a piece 3 inches wide and 5 inches long from 1-inch-thick wood. Wrap a piece of sandpaper around the block and fasten the ends with tacks (Diagram 3). Make two blocks, one of medium sandpaper for shaping the parts and the other of fine sandpaper for finishing them.
Now cement parts S and D and D together. Place one set of discs on a flat surface (Diagram 4). Cement S to the center of these discs and hold the piece of dowel straight up until the cement sets. Cement the other set of discs to the other end of S. To complete the body, roll a piece of heavy paper (P) around the framework formed by parts S, D, and D . The paper should be cut a little wider than the length of the frame (Diagram 5). Apply spots of cement as shown in the diagram and when the cement is dry, roll the paper around the framework several times to make a rigid tube (Diagram 6).
Cement the end of the paper (Diagram 7) and secure it in place with masking tape (Diagram 8). When the cement is dry, remove the tape, cut off the overhanging ends of the paper, and cement the seams (Diagram 9).
A number of the models have tapering bodies and nose cones. These are made in much the same way as the tubular bodies, except that the cardboard discs for one end are made smaller than those for the other. When the model has a particularly sharp-pointed nose, the discs are used only at one end; the other is formed by cutting and sanding down the end of the dowel to a point. (See Diagram 10.)
To make these tapered bodies and nose cones, transfer the fan-shaped pattern (P) shown in the book to the paper (there are instructions at the end of this chapter for transferring the patterns) and cut the paper to the proper size and shape. For the larger models (the CH-10, the Saturn, and the Nova), make three or four copies of these paper patterns. The additional layers of paper will give this section of the body more strength. Then follow the same steps given for forming the tubular bodies and as illustrated in Diagram 10. Form the tips of these nose cones and the others, where needed, with plastic wood.
The bodies of the Titan, the Minuteman, the CH-IO, the Saturn, and the Nova are made of two or more tubes of different sizes. These are cemented together and the connection points finished off with a collar (C), which is made of lightweight cardboard. (See Diagrams n and 12.) The B2 part for the Polaris is made of a strip of paper rolled up into a tube.
The B, B]f and N parts for the Mercury capsule are also made of heavy paper wound on dowel and cardboard-disc frameworks (Diagram 13).
The huge rocket Saturn is made of several tubes, B, B2 , B3, B , and nine other tubes—eight clustered around a center one, B5, to form B1. The parts for the Saturn are glued together as shown in Diagram 14. Hold the tubes for B together with rubber bands until the cement has dried.
Like the Saturn, the body for the giant Nova has a number of parts. These are glued together as shown in Diagram 15. Here again, use rubber bands to hold the tubes for B1and B3together until the cement is set.
When the cement on the body parts and the nose cones is thoroughly dry, apply two or three coats of shellac to them. Be sure each coat is dry before applying the next one. Hang up the parts to dry, using a pin and string (Diagram 16), and then cement them together.
The E and E pieces on the model of the Atlas are made of pieces of wooden dowel shaped on a sandpaper block to match the pattern.
The engine nozzles for the Atlas (E2), the Thor (E1 ) the Jupiter (E), the Polaris (E), and the Nova (E) are made of strips of heavy paper rolled into short tubes and fastened with cement. Cores are not needed for these. The Atlas, the Polaris, and the Nova have several engine nozzles, so for these models you will need several strips of paper of the length shown in the pattern for these parts.
Use wooden dowels to make the bodies of the smaller models—the Honest John, the Nike-Hercules, and the Talos—tapering the nose end with a knife and sandpaper block to match the pattern. First whittle down the end (always remember to whittle in the direction away from you) and then finish the shaping with the sandpaper block. Hold the dowel on the edge of your workbench or table, turning it as you sandpaper it (Diagram 17). Put a dot at the center of the end of the dowel, and taper it to this dot (Diagram 18).
To make the nose of the Honest John bulb-shaped, wrap paste soaked strips of thin paper around the body, gradually building it up to the proper shape (Diagram 19). When the paper strips are thoroughly dry, shape and smooth them with the sandpaper blocks. Make the under part on the tail of the Snark in this same way.
Some of the models have fins (F) and wings (W). The Bomarc also has some tail pieces (T). Make all these of heavy cardboard—carefully transferring the patterns—and cement them to the bodies.
To finish your model, fill all the cracks and joints with plastic wood. Smooth with the fine sandpaper block and apply a coat of shellac. Hang the model up to dry, using a pin and string (Diagram 16). When the shellac is thoroughly dry, spray the model with silver paint or paint it, and it is completed.
HOW TO TRANSFER THE PATTERNS
To transfer the patterns, first trace them, using thin paper you can see through when it is placed over the pattern. With a sharp pencil, carefully trace the pattern onto the paper. To transfer the tracing to the cardboard, wood, or paper, use carbon paper or rub a soft pencil evenly on the back of the tracing paper and smudge with a piece of cloth. Place the tracing on the material to be used for the part and with a sharp pencil carefully trace the pattern.
HOW TO ENLARGE THE PATTERNS
To enlarge a pattern, first make a tracing of it, then rule a frame around it as shown at the right in Diagram 20. Now divide the frame into equal parts. To do this, first divide the frame in half, then these two halves into halves, and so on. Now make a larger frame. If you want to enlarge the pattern to twice the size it is in the book, make this frame twice as long and twice as wide as the frame around the tracing. To enlarge the pattern three times, make this frame three times as long and three times as wide as the smaller one.
To reduce the pattern for the Mercury capsule to half size, make the second frame one half as long and one half as wide as the frame around the tracing.
Divide the larger frame (smaller frame for the Mercury capsule) into the same number of squares as there are in the smaller frame around the tracing. With a pencil, mark in the larger frame the points where the pattern crosses the corresponding lines in the smaller frame. Connect these points with a line, and you will have an enlarged copy of the pattern in the book (see drawing at the left in Diagram 20).
The Atlas, a United States Air Force two-stage surface-to-surface rocket, is an intercontinental ballistic missile, which means that it can be fired from one continent to another. Actually, the Atlas has a potential range of more than 8,000 nautical miles. It was first successfully test-fired in December, 1957, and in November, 1958, made a full-range flight of over 6,000 miles. A later model set a new record for ballistic missile flights on May 20, i960, when it traveled more than one third of the distance around the earth! The missile was launched from Cape Canaveral, Florida, and landed its dummy warhead 9,000 miles away in the Indian Ocean.
In December, 1958, the entire second stage of an Atlas, carrying a 150-pound payload, was put into orbit around the earth. This was in the Project Score experiment, in which a human voice was beamed to the earth from outer space for the first time. The Atlas also launched the Midas II satellite in May, i960.
The Atlas ICBM has three liquid-propellant rocket engines. The two booster engines fall away after about two minutes of operation, and the second-stage sus-tainer engine continues it in flight.
This rocket is 82½ feet long and has a diameter of 10 feet. It is made of stainless steel and weighs 260,000 pounds. Its speed is approximately 18,000 miles per hour. The Atlas has a total thrust of over 360,000 pounds, which is more power than that supplied by 1600 steam engines.
The Titan is a United States Air Force surface-to-surface intercontinental ballistic missile. This two-stage rocket is launched by a 300,000-pound-thrust engine which separates and falls away when burned out. A second engine, with a thrust of 80,000 pounds, then drives the rocket into space at a speed of 17,000 miles per hour. Both engines are liquid-fueled.
The Titan, which is made of aluminum, is larger than the Atlas, but is lighter, weighing 220,000 pounds. Its length is 98 feet and it has a diameter of 10 feet.
The first flight of the Titan was made on February 6, 1959.
The Thor, a United States Air Force surface-to-surface rocket, was the first American intermediate-range ballistic missile to be put into operation. An intermediate-range ballistic missile is one that has a range of between 1200 and 1500 miles.
The Thor—a single-stage missile transportable by air—is propelled by an engine fueled with liquid oxygen and a high grade of kerosene. It has a thrust of over 150,000 pounds and travels at 10,000 miles per hour. This rocket is 65 feet long and 8 feet in diameter. Made of aluminum, it weighs 110,000 pounds.
The Thor was used to launch the Discoverer series of satellites and served as the first stage in a number of other satellite and lunar-probe launchings. It is one of the most successful of our space-exploration vehicles.
The Snark is a United States Air Force surface-to-surface intercontinental guided missile. It differs from our intercontinental ballistic missiles in that it is guided all the way to its target and cannot travel in the vacuum of space because its main engine requires air to operate.
The wings at the center of its slick fuselage and its tail fin give the Snark the appearance of a jet fighter. It is boosted into the air by two solid-fuel rocket engines and is continued in flight by a single turbojet engine. Total thrust is 76,500 pounds.
The Snark is 67 feet long and 5 feet in diameter and weighs about 60,000 pounds. For test purposes it can be fired to its target area, returned to the launching site, and landed safely, to be used in further testing. Its range is 5500 nautical miles.
The Bomarc, a United States Air Force surface-to-air supersonic interceptor, is an air-defense weapon designed to attack enemy bombers before they reach their target. It is launched vertically from a launching shelter.
A solid-fuel rocket engine powers the Bomarc to high speed, and then two ramjet engines take over to sustain it in flight. Like the Snark, the Bomarc needs air to operate because it does not carry its own oxidizer aboard (oxygen is needed to make the fuel burn).
The Bomarc is about 46 feet long and 35 inches in diameter. It weighs in the vicinity of 16,000 pounds and has a range of 250 to 400 nautical miles.
The Minuteman, like the Atlas and the Titan, is an Air Force surface-to-surface intercontinental ballistic missile with a range of 5500 nautical miles. It can be fired for shorter distances by dropping off one or more of its three stages while in flight. All three stages are equipped with solid-fuel rocket engines.
The Minuteman, which has a top speed of over 15,000 miles per hour, is about 60 feet long and 6 feet in diameter and weighs approximately 65,000 pounds.
The first stage alone has a thrust of 160,000 pounds.
Some Minutemen will be stored in bomb-proof shelters beneath the ground, ready for instant firing. Others will be based on railroad cars which will roam the country's thousands of miles of railroad tracks. This not only makes the weapon mobile but also helps to keep it safe from surprise attack by enemy forces.
This missile made its first successful test flight of more than 4,000 miles on February 1, 1961.
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