The Boy Mechanic Part 76

This being done, give the paper a thin and even coating of glue, which must be quite hot and put on as quickly

[Ill.u.s.tration: Ancient Helmets]

as possible. Put on a second layer of paper as carefully as before, then another coating of glue, and so on, until there are from four to six coats of glue and paper. When dry, the paper coating should be quite stout and strong enough for the helmet to be used for ornamental purposes. Before taking it off the model, which should be no difficult matter, owing to the clay being oiled, trim off any ragged edges of paper with a sharp knife, and smooth and finish all over with some fine sandpaper. The paper is then given a thin coat of glue and sections of tinfoil stuck on to give it a finished appearance. When the helmet is off the model, make holes with a small awl at equal distances, through which to insert some fancy bra.s.s nails, bending the points over and flat against the inside of the helmet.

A vizor helmet is shown in Fig. 5. This helmet has a movable vizor in the front that can be lifted up, a crest on top, and around the neck a narrow gorget which rests upon the wearer's shoulders. The whole helmet with the exception of the vizor, should be modeled and made in one piece. The vizor can then be made and put in place with a bra.s.s-headed nail on each side. The oblong slits in front of the vizor must be carefully marked out with a pencil and cut through with a knife or chisel.

In Fig. 6 is shown an Italian casque of a foot soldier of the sixteenth century. This helmet may have the appearance of being richly engraved as shown in one-half of the drawing, or, a few lines running down, as seen in the other part of the sketch, will make it look neat. The band is decorated with bra.s.s studs.

An Italian caba.s.set of the sixteenth century is shown in Fig. 7.

This helmet is elaborately decorated with fancy and round-headed nails, as shown: in the design.

In Fig. 8 is shown a large ba.s.sinet with a hinged vizor which comes very much forward, so as to allow the wearer to breathe freely. This helmet was worn about the sixteenth century, and was probably used for tilting and tournaments.

A burgonet skull-cap of the seventeenth century is shown in Fig.

9. The vizor is composed of a single bar of metal, square in shape, which slides up and down in an iron socket attached to the front of the helmet, and is held in any position by a thumbscrew as shown in the ill.u.s.tration.

A hole in the peak of the helmet allows it to hang in front of the wearer's face. This contrivance should be made of wood, the helmet to be modeled in three pieces, the skullcap, peak and lobster sh.e.l.l neck guard in one piece, and the ear guards in two pieces, one for each side. The center of the ear guards are perforated.

All of the helmets are made in the same manner as described for Fig. 1. They are all covered with tinfoil.

** How to Repair Linoleum [273]

A deep crack or fissure right in front of the kitchen cabinet spoiled the appearance of the new linoleum. The damaged spot was removed with a sharp knife and from a left-over sc.r.a.p a piece was cut of the same outline and size. The edges were varnished and then the patch was set in the open s.p.a.ce. The linoleum was given a good coat of varnish making it more durable. When perfectly dry, the piecing could not be detected.

--Contributed by Paul Keller, Indianapolis, Indiana.

** How to Make an Electric Stove [273]

The parts necessary for making an electric stove are: Two metal pie plates of the same size; 4 lb. of fire clay; two ordinary binding posts; about 1 lb. of mineral wool, or, if this cannot be obtained, thick sheet asbestos; one oblong piece of wood, 1 in.

thick, 12 in. wide and 15 in. long; one small switch; one fuse block; about 80 ft. of No. 22 gauge resistance wire, German-silver wire is better, as it stands a higher temperature; two middle-sized stove bolts with nuts; one gla.s.s tube, about 1/4 in.

in diameter and 9 in. long, which can be bought from a local druggist, and two large 3-in. screws.

If a neat appearance is desired, the wood can be thoroughly sandpapered on one side and the corners and edges rounded off on the upper side. Punch holes in one of the pie plates, as shown in Fig. 1. The two holes, E and F, are on the rim and should be exactly on a line with the hole D punched in the center. The holes B and C are about 3 in. apart and should be at equal distances from the center hole D. The rim of the second plate is drilled to make two holes, AA, Fig. 2, that will match the holes E and F in the first plate, Fig. 1. A round collar of galvanized iron, FF, Fig. 4, 3 in. high, is made with a diameter to receive the first plate snugly. Two small flaps are cut and turned out and holes punched in their centers, AA, to receive screws for holding it to the base. Two bolts are soldered in the holes E and F, Fig. 1, and used to hold the

[Ill.u.s.tration: Details of Electric Stove]

rims of both plates together, when they are placed in opposite positions, as shown in Fig. 4. This will make an open s.p.a.ce between the plates. The collar is then screwed to one end of the base, as shown in Fig. 2.

Two holes are bored through the base to correspond with the holes D and A in the bottom plate. The gla.s.s tube is cut to make two pieces, each 4-1/2 in. long. This can be done easily by filing a nick in the tube at the proper point and breaking it. These tubes are forced into the holes bored in the base, and, if the measurements are correct, should extend about 1/4 in. above the collar. The mineral wool, JJ, Fig. 4, is then packed down inside the collar, until it is within 1 in. of the top. This will allow the plate, Fig. 1, to rest on the wool and the ends of the gla.s.s tubes, GG, Fig. 4, to project through the holes D and A of the plate, Fig. 1. The rim of the plate should be level with the top edge of the collar. If asbestos is used, the sheets should be cut into disks having the same diameter as the inside of the collar, and holes cut to coincide with the holes D and A of the plate. The small sc.r.a.ps should be dampened and made into pulp to fill the s.p.a.ce H, Fig. 4. The plate, Fig. 1, is held to the base by two screws which are run through the holes BC and take the position shown by DD, Fig. 4.

The two binding-posts are attached on the base at D, Fig. 2, also the switch B and the fuse block C, holes being bored in the base to make the wire connections. The reverse side of the base, with slits cut for the wires, is shown in Fig. 3. The points marked BB are the gla.s.s tubes; AA, the holes leading to the switch; and C, the fuse block. The wires run through the gla.s.s tubes GG, Fig. 4, are allowed to project about 1 in. for connections.

The best way to find the correct length of the resistance wire is to take a large clay or drain tile and wind the wire tightly around it, allowing a s.p.a.ce between each turn. The tile is then set on its side with a block or brick under each end. It should not be set on end, as the turns of the wires, when heated, will slip and come in contact with each other, causing a short circuit.

When the tile is in place, a short piece of fuse wire is fastened to each of its two ends. A 5-ampere fuse wire is about strong enough. A connection is made to these two wires from an electric-light socket. The wire will get hot but probably remain the same color. If this is the case, one of the feed wires is disconnected from the fuse wire and gradually moved farther down the coil until a point is found where the resistance wire glows a dull red. This point marks the proper length to cut it, as the wire should not be allowed to become any hotter. If the wire gets bright hot when the current is turned on, more wire should be added. The wire is then made into a long coil by winding it around a large wire nail. The coils should be open and about 1/8 in.

apart.

Next, the fire clay is moistened and well mixed, using care not to get it too wet. It should have the proper consistency to mould well. The clay, II, Fig. 4, is then packed in the first plate to a height of about 1/4 in. above the rim. While the clay is damp, one end of the coil is connected with the wire in the central gla.s.s tube, and the coil laid in a spiral winding on the damp clay, KK, and pressed into it. When this is done, the other end is connected to the wire projecting from the outer gla.s.s tube. As these connections cannot be soldered, the ends of the wires should be twisted closely together, so that the circuit will not become broken. Make sure that the coils of wire do not touch each other or the top plate. The fuse wire (about 5 amperes) is put into the fuse block, and wires with a socket adapter connected to the two binding-posts. The top plate is put in place and screwed down.

This completes the stove.

It should be set aside in a warm place for a few days to dry out the packing. If it is not thoroughly dry, steam will form when the current is applied. It should not be left heated in this condition. The top plate is used when cooking and removed when making toast.

--Contributed by R. H. Cnonyn, St. Catherines, Can.

** How to Make Weights for Athletes [274]

Many times boys would like to make their own shots and weights for

[Ill.u.s.tration: Mold for the Lead]

athletic stunts, but do not know how to go about it to cast the metal. In making a lead sphere as shown in the ill.u.s.tration, it is not necessary to know the method of molding. The round lead weight for shot-putting or hammer throwing can be cast in a hollow cardboard or pressed-paper ball, sold in department and toy stores for 10 cents. Cut a 1/2-in. hole in the ball as shown in Fig. 1 and place it with the hole up in damp sand and press or tamp the sand lightly around the ball as shown in the section, Fig. 2.

Cover over about 1 in. deep. A wood plug inserted in the hole will prevent any sand falling inside. When the sand is tamped in and the plug removed, it leaves a gate for the metal. Pour melted lead into the gate until it is full, then, when cool, shake it out from the sand and remove the charred paper. A file can be used to remove any rough places. The dry paper ball prevents any sputtering of the hot lead.

--Contributed by W. A. Jaquythe, Richmond, Cal.

** Removing Pies from Pans [275]

Sometimes the juices from a hot pie make it stick to the pan so tightly that a knife blade must be run under to cut it loose. If a knife with a flexible blade is not used, the pie will be damaged.

[Ill.u.s.tration: Separating Pies from Pans]

If the pie pans are provided with the simple attachment shown in the accompanying sketch, the baked dough can be separated from the tin with one revolution of the cutter. The cutter is made from a piece of heavy tin, bent to the same outline as the inside of the pan and pivoted at its center.

** Stretcher for Drying Photograph Prints [275]

A quick and convenient way to dry prints is to place them on a cheesecloth stretcher. Such a stretcher can be made on a light wood frame, constructed of 3/4-in. square material in any size, but 12 by 24 in. is large enough. The end pieces B are fastened on top of the long side pieces A, and the cheesecloth C stretched and tacked over them, as shown.

The prints should be placed face up on the cloth, and the frame set near a window. If the stretcher is made in

[Ill.u.s.tration: Cloth on the Frame]

this way, the air can enter from both top and bottom, and the prints will dry rapidly. Several of these frames can be stacked and a large number of prints thus dried at the same time.

--Contributed by Andrew G. Thorne, Louisville, Ky.

** A Temporary Funnel [275]

The amateur photographer often has some solution which he desires to put into a bottle which his gla.s.s funnel will not fit, says the Photographic Times. The funnel made by rolling up a piece of paper usually allows half of the solution to run down the outside of the bottle, thereby causing the amateur to be dubbed a "musser," A better way is to take an ordinary envelope and cut it off as shown by the dotted lines. Then clip a little off the

[Ill.u.s.tration: Paper Funnel]

point, open out, and you have a funnel that will not give any trouble. It is cheap and you can afford to throw it away when dirty, thereby saving time and washing.