Boiy Mechanic - pdf

Boiy Mechanic - pdf

(Parte 1 de 7)

Project Gutenberg's The Boy Mechanic: Volume 1, by Popular Mechanics

This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at

Title: The Boy Mechanic: Volume 1 700 Things For Boys To Do

Author: Popular Mechanics Release Date: June 18, 2004 [EBook #12655] Language: English Character set encoding: ISO-8859-1 *** START OF THIS PROJECT GUTENBERG EBOOK THE BOY MECHANIC: VOLUME 1 ***

Produced by Don Kostuch

The Boy Mechanic Vol. 1 700 Things for Boys to Do 800 Illustrations Showing How

Jack Mansfield + Ed

Jan 28, 1938 August 1916 From Mother

Transcriber’s Notes:

This text accurately reproduces the original book except for adherence to Project Gutenburg guidelines. Each project title is followed by its original page number to allow use of the alphabetical contents (index) at the end of the book. The book used very complex typesetting to conserve space. This transcription uses simple one-column linear layout.

The text only version is of limited use because of the widespread occurrence of diagrams and illustrations. Use the pdf version for the complete text.

Many projects are of contemporary interest—magic, kites and boomerangs for example. Try a “Querl” for starters.

There are many projects of purely historical interest, such as chemical photography, phonographs, and devices for coal furnaces.

Another class of projects illustrate the caviler attitude toward environment and health in 1913. These projects involve items such as gunpowder, acetylene, hydrogen, lead, mercury, sulfuric acid, nitric acid, cadmium, potassium sulfate, potassium cyanide, potassium ferrocyanide, copper sulfate, and hydrochloric acid. Several involve the construction of hazardous electrical devices. Please view these as snapshots of culture and attitude, not as suggestions for contemporary activity.

Be careful and have fun or simply read and enjoy a trip into yesterday.

Poster's Note: The PDF format of this e-book was generated from the RTF by OpenOffice. Any future revisions needed to the PDF can be made the same way.

How to Make a Glider (See page 171) How to Make a Glider (See page 171)




A Model Steam Engine [1]

The accompanying sketch illustrates a two-cylinder single-acting, poppet valve steam engine of home construction.

The entire engine, excepting the flywheel, shaft, valve cams, pistons and bracing rods connecting the upper and lower plates of the frame proper, is of brass, the other parts named being of cast iron and bar steel.

The cylinders, G, are of seamless brass tubing, 1-1/2 in. outside diameter; the pistons,

H, are ordinary 1-1/2 in. pipe caps turned to a plug fit, and ground into the cylinders with oil and emery. This operation also finishes the inside of the cylinders.

The upright rods binding the top and bottom plates are of steel rod about 1/8-in. in diameter, threaded into the top plate and passing through holes in the bottom plate with hexagonal brass nuts beneath.

The valves, C, and their seats, B, bored with a countersink bit, are plainly shown. The valves were made by threading a copper washer, 3/8 in. in diameter, and screwing it on the end of the valve rod, then wiping on roughly a tapered mass of solder and grinding it into the seats B with emery and oil.

The valve rods operate in guides, D, made of 1/4-in. brass tubing, which passes through the top plate and into the heavy brass bar containing the valve seats and steam passages at the top, into which they are plug-fitted and soldered.

The location and arrangement of the valve seats and steam passages are shown in the sketch, the flat bar containing them being soldered to the top plate. The steam chest, A, over the valve mechanism is constructed of 1-in.

Engine Details square brass tubing, one side being sawed out and the open ends fitted with pieces of 1/16 in. sheet brass and soldered in. The steam inlet is a gasoline pipe connection such as used on automobiles.

The valve-operating cams, F, are made of the metal ends of an old typewriter platen, one being finished to shape and then firmly fastened face to face to the other, and used as a pattern in filing the other to shape. Attachment to the shaft, N, is by means of setscrews which pass through the sleeves.

The main bearings, M, on the supports, O, and the crank-end bearings of the connecting rods, K, are split and held in position by machine screws with provision for taking them up when worn.

portion of the cam and allows the valve to seat

The exhausting of spent steam is accomplished by means of slots, I, sawed into the fronts of the cylinders at about 1/8 in. above the lowest position of the piston's top at the end of the stroke, at which position of the piston the valve rod drops into the cutout

All the work on this engine, save turning the pistons, which was done in a machine shop for a small sum, and making the flywheel, this being taken from an old dismantled model, was accomplished with a hacksaw, bench drill, carborundum wheel, files, taps and dies. The base, Q, is made of a heavy piece of brass.

The action is smooth and the speed high. Steam is supplied by a sheet brass boiler of about 3 pt. capacity, heated with a Bunsen burner. --Contributed by Harry F. Lowe, Washington, D. C.

Magic Spirit Hand [2]

The magic hand made of wax is given to the audience for examination, also a board which is suspended by four pieces of common picture-frame wire. The hand is placed upon the board and answers, by rapping, any question asked by members of the audience. The hand and the board may be examined at any time and yet the rapping can be continued, though surrounded by the audience.

The Magic Wand, London, gives the secret of this spirit hand as follows: The hand is prepared by concealing in the wrist a few soft iron plates, the wrist being afterwards bound with black velvet as shown in Fig. 1. The board is hollow, the top being made of thin veneer (Fig. 2). A small magnet, A, is connected to a small flat pocket lamp battery, B. The board is suspended by four lengths of picture-frame wire one of which, E, is

Wax Hand on Board and Electrical Connections connected to the battery and another, D, to the magnet. The other wires, F and G, are only holding wires. All the wires are fastened - to a small ornamental switch, H, which is fitted with a connecting plug at the top. The plug can be taken out or put in as desired.

The top of the board must be made to open or slide off so that when the battery is exhausted a new one can be installed. Everything must be firmly fixed to the board and the hollow space filled in with wax, which will make the board sound solid when tapped.

In presenting the trick, the performer gives the hand and board with wires and switch for examination, keeping the plug concealed in his right hand. When receiving the board back, the plug is secretly pushed into the switch, which is held in the right hand. The hand is then placed on the board over the magnet. When the performer wishes the hand to move he pushes the plug in, which turns on the current and causes the magnet to attract the iron in the wrist, and will, therefore, make the hand rap. The switch can be made similar to an ordinary push button so the rapping may be easily controlled without detection by the audience.

Making Skis and Toboggans [3]

During the winter months everyone is thinking of skating, coasting or ski running and jumping. Those too timid to run down a hill standing upright on skis must take their pleasure in coasting or skating.

The ordinary ski can be made into a coasting ski-toboggan by joining two pairs together with bars without injury to their use for running and jumping. The ordinary factory-made skis cost from $2.50 per pair up, but any boy can make an excellent pair far 50 cents.

In making a pair of skis, select two strips of Norway pine free from knots, 1 in. thick, 4 in. wide and 7 or 8 ft. long. Try to procure as fine and straight a grain as possible. The pieces are dressed thin at both ends leaving about 1 ft. in the center the full thickness of 1 in., and gradually thinning to a scant 1/2 in. at the ends. One end of each piece is tapered to a point beginning 12 in. from the end. A groove is cut on the under side, about 1/4 in. wide and 1/8 in. deep, and running almost the full length of the ski. This will make it track straight and tends to prevent side slipping. The shape of each piece for a ski, as it appears before bending, is shown in Fig. 1.

The pointed end of each piece is placed in boiling water for at least 1 hour, after which the pieces are ready for bending. The bend is made on an ordinary stepladder. The pointed ends are stuck under the back of one step and the other end securely tied to the ladder, as shown in Fig. 2. They should remain tied to the ladder 48 hours in a moderate temperature, after which they will hold their shape permanently.

The two straps, Fig. 3, are nailed an a little forward of the center of gravity so that when the foot is lifted, the front

Fig. 1, Fig. 2, Fig. 3 – Forming the Skis of the ski will be raised. Tack on a piece of sheepskin or deer hide where the foot rests, Fig. 4. The best finish for skis is boiled linseed oil. After two or three

Fig. 4 – The Toe Straps applications the under side will take a polish like glass from the contact with the snow. The ski-toboggan is made by placing two pairs of skis together side by side

Fig. 5 – Ski-Toboggan and fastening them with two bars across the top. The bars are held with V-shaped metal clips as shown in Fig. 5. --Contributed by Frank Scobie, Sleepy Eye, Minn.

Homemade Life Preserver [4]

Procure an inner tube of a bicycle tire, the closed-end kind, and fold it in four alternate sections, as shown in Fig. 1. Cut or tear a piece of cloth into strips about 1/2 in. wide, and knot them together. Fasten this long strip of cloth to the folded tube and weave it alternately in and out, having each

Fig. 1, Fig. 2 -- Inner Tube and Cover run of the cloth about 4 in. apart, until it is bound as shown in Fig. 1.

Make a case of canvas that will snugly fit the folded tube when inflated. The straps that hold the preserver to the body may be made of old suspender straps. They are sewed to the case at one end and fastened at the other with clasps such as used on overall straps. The tube can be easily inflated by blowing into the valve, at the same time holding the valve stem down with the teeth. The finished preserver is shown in Fig. 2.

How to Make Boomerangs [4]

When the ice is too thin for skating and the snow is not right for skis, about the only thing to do is to stay in the house. A boomerang club will help to fill in between and also furnishes good exercise for the muscles of the arm. A boomerang can be made

Bending and Cutting the Wood of a piece of well seasoned hickory plank. The plank is well steamed in a wash boiler or other large kettle and then bent to a nice curve, as shown in Fig. 1. It is held in this curve until dry, with two pieces nailed on the sides as shown.

After the piece is thoroughly dried out, remove the side pieces and cut it into sections with a saw, as shown in Fig. 2. The pieces are then dressed round. A piece of plank 12 in. wide and 2 ft. long will make six boomerangs.

To throw a boomerang, grasp it and hold the same as a club, with the hollow side away from you. Practice first at some object about 25 ft. distant, and in a short time the thrower will be able to hit the mark over 100 ft. away. Any worker in wood can turn out a great number of boomerangs cheaply. --Contributed by J. E. Noble, Toronto, Ontario.

How to Make an Eskimo Snow House [5] By GEORGE E. WALSH

Playing in the snow can be raised to a fine art if boys and girls will build their creations with some attempt at architectural skill and not content themselves with mere rough work. Working in snow and ice opens a wide field for an expression of taste and invention, but the construction of houses and forts out of this plastic material provides the greatest amount of pleasure to the normally healthy boy or girl.

The snow house of the Eskimo is probably the unhealthiest of buildings made by any savage to live in, but it makes an excellent playhouse in winter, and represents at the same time a most ingenious employment of the arch system in building. The Eskimos build their snow houses without the aid of any scaffolding or interior false work, and while there is a keystone at the top of the dome, it is not essential to the support of the walls. These are self-supporting from the time the first snow blocks are put down until the last course is laid.

The snow house is of the beehive shape and the ground plan is that of a circle. The circle is first laid out on the ground and a space cleared for it. Then a row of snow blocks is laid on the ground and another course of similar blocks placed on top. The snow blocks are not exactly square in shape, but about 12 in. long, 6 in. high and 4 or 5 in. thick. Larger or smaller blocks can be used, according to size of the house and thickness of the walls.

First, the snow blocks must be packed and pressed firmly into position out of moist snow that will pack. A very light, dry snow will not pack easily, and it may be necessary to use a little water. If the snow is of the right consistency, there will be no trouble in packing and working with it. As most of the blocks are to be of the same size throughout, it will pay to make a mold for them by forming a box of old boards nailed together, minus the top, and with a movable bottom, or rather no bottom at all. Place the four sided box on a flat board and ram snow in it, forcing it down closely. Then by lifting the box up and tapping the box from above, the block will drop out. In this way blocks of uniform size are formed, which makes the building simpler and easier.

While one boy makes the blocks another can shave them off at the edges and two others can build the house, one inside of the circle and the other outside. The Eskimos build their snow houses in this way, and the man inside stays there until he is completely walled in. Then the door and a window are cut through the wall.

Laying the Snow Bricks

Three-Room Snow House

Each layer of snow blocks must have a slight slant at the top toward the center so that the walls will constantly curve inward. This slant at the top is obtained better by slicing off the lower surfaces of each block before putting it in its course. The top will then have a uniform inward slant.

The first course of the snow house should be thicker than the others, and the thickness of the walls gradually decreases toward the top. A wall, however, made of 6-in. blocks throughout will hold up a snow house perfectly, if its top is no more than 6 or 7 ft. above the ground. If a higher house is needed the walls should be thicker at the base and well up toward the middle.

The builder has no mortar for binding the blocks together, and therefore he must make his joints smooth and even and force in loose snow to fill up the crevices. A little experience will enable one to do this work well, and the construction of the house will proceed rapidly. The Eskimos build additions to their houses by adding various domeshaped structures to one side, and the young architect can imitate them. Such domeshaped structures are shown in one of the illustrations.

(Parte 1 de 7)