Chapter XXV: Part II: Construction (2)

Not having the room to spare for the ordinary hose reel, I used as a substitute a piece of wire bent into the shape of a letter S and with its aid coiled the hose in a manner to expel the water and leave it in shape for storing.

The hook A is sprung around the hose about 5 ft. from the connection joint and remains there permanently. The end of the hose with the connection C is then brought around in a circle and forced into the hook B. This forms the start for the coil and the hose is easily rolled up to the nozzle, the water being expelled during the operation.--Contributed by F. H. Aldrich, Toledo, Ohio.

Addressing a Roll of Papers

When addressing rolled-up papers it is difficult to write on the curved surface. The papers also have a tendency to roll away. By placing the roll in the hollow on the front edge of a large book, as shown in the sketch, it will be found easy to write on the wrapper.--Contributed by W. P. Shaw, Toronto, Canada.

Repairing the Bruised Sides of a Motorboat

When the sides of a boat become scored or bruised scrape the parts clean and fill the depressions with wood cement. The wood cement or stick cement, as it is called, can be procured from a paint store. Heat the cement with a blowtorch and apply it to the bruised parts. Use a heated putty knife to smooth the cement and make the surface level. After sandpapering the fills and applying a coat of paint the boat sides will look as good as new. The cement will not chip or fall out.--Contributed by Henry Beck, Bronx, New York.

How to Make an Electric Lamp Flasher

Procure two pieces of metal, one of brass and the other of sheet iron, 5 in. long, 1/2 in. wide, and 1/32 in., or just a little more, in thickness. Bend the brass strip into the form shown in Fig. 1, then place the brass piece on top of the iron and drill the holes A and B indicated in Fig. 2. After the brass piece has been bent, as shown in Fig. 1, it will of course be shorter than the iron strip and the iron strip must be cut off, or a brass strip a little longer than 5 in. can be secured and cut the same length as the iron strip after it is bent. The holes A and B should be 3/32 in. in diameter. The next thing to do will be to wind a heating coil about the brass strip. Wrap a very thin layer of sheet asbestos about the brass strip, and wind on the strip 18 ft. of No. 34 gauge bare superior resistance wire. Use a thread about .006 in. in diameter to separate the various turns. This thread can be removed after the winding is completed and the ends have been fastened. Rivet the iron and brass pieces together with a small brass rivet in the hole A, Fig. 2. After the two pieces are riveted together bend them into the form shown in Fig. 4 and then drill the two 1/8-in. holes C and D, as shown in Fig. 2. Tap the hole B, Fig. 2, to take a small machine screw.

The base is constructed as follows: Procure a piece of slate, 5-3/8 in. long, 1-1/2 in. wide, and 1/2 in. in thickness. Drill the holes indicated in Fig. 3. The four corner holes are for mounting the flasher in its containing case, and should be about 1/8 in. in diameter. The holes E, F, G, and H should be 1/8 in. in diameter and countersunk with a 3/8-in. square-ended drill, on the under side, to a depth of 3/16 or 1/4 in. Cut from some 1/16-in. sheet brass a piece 1-3/8 in. long, and 1/2 in. wide. Drill two 1/8-in. holes in this piece, 7/8 in. apart and equally spaced from the ends. Procure four 1/8-in. brass bolts, two 1/2 in. in length, and two 1 in. in length. Secure four small washers and two additional nuts. Mount the combined iron and brass strip on the slate base, using a long and short bolt as shown in Fig. 4. One terminal of the winding should be placed under the head of the bolt J. Place a washer, K, between the head of the bolt and the wire. The brass strip L can now be mounted in a similar manner, as shown in Fig. 4. Place the other end of the winding under the head of the bolt M.

Obtain a small screw, N, Fig. 4, of such a length that its point will reach the brass strip L when the screw is placed in the hole B, Fig. 2. A lock nut, O, should be provided for this screw so that it will remain in adjustment. The point of the screw and the point on the brass plate where the screw touches should be of platinum, as the brass will not withstand the high temperature of the arc formed when the circuit is broken.

A metal box should now be provided to serve as a containing case and the flasher is complete. This box should be of such design and construction that it will comply with the requirements of the electrical inspection department having jurisdiction over the locality where the flasher is to be used.

The flasher should be connected in series with the lamp, the wires being fastened under the nuts on the bolts P and R, Fig. 4, and the screw N adjusted so that it lacks a small fraction of an inch of making contact with the brass plate when there is no current in the winding. When the switch is turned on there will be a current through the lamp and winding in series. The brass strip will be heated more than the iron and it will expand more, thus forcing the point of the screw N down upon the brass plate, which will result in the winding about the brass strip being shorted and the full voltage will be impressed upon the lamp, and it will burn at normal candlepower. When the coil is shorted there will of course be no current in its winding and the brass strip will cool down, the screw N will finally be drawn away from contact with the brass plate, and the winding again connected in series with the lamp. The lamp will apparently go out when the winding is in series with it, as the total resistance of the lamp and winding combined will not permit sufficient current to pass through the lamp to make its filament glow. The time the lamp is on and off may be varied to a certain extent by adjusting the screw N.

Timing Photograph Prints

An amateur photographer insists that a timing clock in the darkroom is a needless luxury. In order to time printing exposures, which he does with a pendant tungsten light under a reflecting shade, he simply fastens the electric-light cord so that the lamp and shade will act like a pendulum bob which beats the seconds. Of course he makes no effort to be exact, but if the distance between the lamp and the point of suspension of the cord be about 39 or 40 in., the beats will be very nearly seconds. When the light is turned on, it is started swinging, and the operator can thus easily count seconds with sufficient accuracy, and, besides, it readily furnishes a guide for duplicating printing results.

The same principle can be applied to camera exposures, if so desired, by the following plan. Select some suitable place on the under side of the tripod plate, as, for instance, the screw head, and fasten a small string, having a weight attached to it about 39 in. from the point of support. Like the swinging lamp, this device too, will beat seconds. For convenience, one of the tripod legs may be marked to indicate the length of string needed, so that the operator at any time can quickly fasten a string, measure off the right length on the tripod leg, attach a bunch of keys, a knife, or any other convenient weight, even a small stone, and have a second-beating pendulum for time exposures.--Contributed by F. B. Lambert, Chicago.

Supports for Camp-Fire Utensils

The sketch shows how to make a standard or support to hold cooking utensils over a camp fire. The main part or stake is made of a piece of gas pipe, on one end of which is turned an ordinary coupling, Fig. 1. This is used to furnish a strong head when the stake is driven into the ground. The rings and supports for the utensils are made of heavy wire bent into the shape required to hold the respective vessels. The sketch, Fig. 2, shows the manner of shaping the wires.

A Rotary Tuning Coil

The rotary tuner shown in the sketch was designed by a correspondent of Modern Electrics. The circle is cut from 3/4-in. stock, 1 in. wide and well covered with insulating material. It is then wound with No. 24 single cotton-covered copper wire so that the coils will lie flat. All the arms are of 1/4-in. square brass. The supports are smaller in section. Sliders are mounted on the ends of the long arms and are kept in place by setscrews.

The insulation on the wire is removed with a small piece of sandpaper pasted on a block of wood. This should be temporarily fastened to the revolving lever at the point where the contact is wanted, then the lever is turned until the insulation is removed. The wiring diagram shows the location of the tuning coil in the line.

Preparing Sheet Music for Turning

Each page on sheet music having three or more pages should be cut 1/4 in. shorter than the preceding page, as shown by the dotted lines in the sketch. This will enable the player to quickly turn the pages one at a time.--Contributed by Chas. Homewood, Waterloo, Ia.

Toy Parachute Cut-Away for Kite Lines

An interesting pastime while flying kites is to attach large toy parachutes to the lines and have some device to drop them when they are at a great height. In Fig. 1 is shown how the parachute is dropped by the burning of a piece of punk.

Another method is shown in Fig. 2. It is only necessary to send a piece of paper or cardboard along the line and when it strikes the wire coil A (Fig. 2) the part B slides out of the loops C, the end D will then fall and disengage the loop G on the end of the parachute string. The wires E and F are twisted around the kite string.--Contributed by Thos. De Loof, Grand Rapids, Michigan.

How to Make an Electric Furnace

A small electric furnace that will be very serviceable in a laboratory may be made as follows:

First procure a small clay flowerpot, about 4 in. in diameter at the bottom, and also a small clay crucible, about 2 in. in diameter at the bottom and at least 1 in. less in height than the flowerpot, and having as nearly as possible the same slope to its sides as the pot. Now obtain a small quantity of asbestos compound and pack it around the small crucible inside the flowerpot. Make sure the crucible is in the exact center of the flowerpot and that their tops are even with each other. Assuming that ordinary electric-light carbons are to be used, which are about 1/2 in. in diameter, drill two 5/8-in. holes, exactly opposite each other, through the walls of the flowerpot and asbestos compound so that they enter the crucible about 3/4 in. above its bottom on the inside. A suitable lid for the furnace may be made from 1/4-in. sheet asbestos and should be large enough to cover the top of the flowerpot.

The feeds and supports for the carbon electrodes are constructed as follows: Procure two pieces of 1/8-in. brass, 1 in. wide and 9 in. long. Cut a 1/8-in. groove lengthwise in the center of these pieces to within 1-1/2 in. of each end, as shown in Fig. 1. Drill four 1/8-in. holes, AA, in each piece, a 3/8-in. hole, B, in one end and a 3/16-in. hole, C, in the other end. Now bend the ends up at right angles to the remainder of the piece along the dotted lines shown at D and E. Next obtain two 3/8-in. rods, 10-3/16 in. long. Turn one end of each down to a 3/16-in. diameter for a distance of 3/8 in. From that point thread the same end of the rods for a distance of 6 in. Drill a 1/16-in. hole in each end of the rods a little less than 1/4 in. from the ends. The dimensions of the rods are given in Fig. 2. Two small rubber or wooden handles, similar to the one shown in Fig. 3, should now be made and fastened to the large ends of the rods by means of 1/16-in. steel pins. Obtain two pieces of brass of approximately the following dimensions: 1 in. by 1 in. by 3 in. Drill four holes in each of these pieces as shown in Fig. 4. The hole H should be just large enough to allow the carbon to enter, or about 1/2 in. in diameter. The hole G should be tapped to take a 1/4-in. machine screw, the hole F should be threaded so that the threaded rods will enter, and a small binding post should be mounted on a lug fastened in the hole J. Cut away one end of this piece as shown in Fig. 4 until it is a little less than 1/8 in. in thickness, or so it will enter the grooves cut in the brass strips.

The parts of the furnace are now ready to assemble, which may be done as follows: Procure a piece of well seasoned board, hard wood if possible, about 1 in. thick, 8 in. wide and perhaps 20 in. long. Cover one side of this board and the edges with some 1/8-in. sheet asbestos. Now place the flowerpot in the exact center and then mount the grooved brass strips one on either side of it with the longest dimension parallel to the longest dimension of the board and the inside end about 1 in. from the side of the pot. The end with the 3/16-in. holes should be next to the pot. Assemble the parts of the carbon feeds and then cut out some circular disks of asbestos to place under the flowerpot so as to raise it to such a position that the holes in its sides will be on a line with the carbon rods. Three long screws should now be placed in the board, forming the base, in such a position as to hold the flowerpot always in place. This completes the furnace proper, which is shown in Fig. 5.

The furnace can now be put into operation provided there is a suitable current rheostat to connect in series with the carbon arc to prevent an excessive current being taken from the line. If such a rheostat is not available, a serviceable one may be made as follows:

Obtain two pieces of 1/16-in. sheet iron, 6 by 6 in., that are to form the end plates. Cut off the corners of one piece so as to form an octagon and drill a number of 1/8-in. and 1/4-in. holes in it, as shown in Fig. 6. Bend the corners of the other piece down along the dotted lines marked L, Fig. 7, and then make a second bend in each corner along the dotted lines K, so that the outermost portion of the corner is parallel to the main portion of the piece. Drill a number of 1/8-in. holes in this piece as indicated. A 3-in. opening should be cut in the center of this piece to give access to the interior of the completed rheostat. Now obtain eight 3/8-in. iron rods, 10 in. long. Drill and tap each end of these rods to accommodate a 1/8-in. machine screw. Wrap several layers of thin sheet asbestos around each rod and tie it in place with some thread. These rods should now be fastened between the end plates by means of a number of iron machine screws. Mount four back-connected binding posts on the plate shown in Fig. 6, making sure they are insulated from the plate by means of suitable bushings and washers.

Procure a small quantity of No. 14 gauge iron wire. Fasten one end of the wire under the head of the screw holding one of the binding posts in place and then wind it around the rods about 20 times, making the distance between the turns equal to the diameter of the wire. After winding on the 20 turns, attach a short piece of wire to the main wire and fasten the free end of the short piece to one of the other binding posts. Wind on 20 more turns, and make another connection to the third binding post, then complete the winding and attach the end to the remaining binding post. Different amounts of this resistance can now be connected in series with the arc by changing the connections from one binding post to another. The rheostat may be located on a bracket fastened to the wall, but care must be taken not to place it in such a position that it will come into contact with inflammable material. As an extra precaution, the circuit should be properly fused.

Cleaning Brass Articles

Embossed or undercut brass work may be easily cleaned by boiling the pieces in a strong solution of caustic soda or lye, and then immersing them in a mixture of hydrochloric acid, 6 parts; water, 2 parts, and nitric acid, 1 part, until they become covered with a dark deposit. Take them from the solution and remove the black substance with a fine scratch brush. After cleaned in this manner, rinse in hot water and dry in hot sawdust.

A fine orange-yellow tinge may be given to the brass by substituting an equivalent weight of powdered alum for the nitric acid in the solution.--Contributed by Mrs. Richard F. Pohle, E. Lynn, Mass.

A Whetting Block

A handy tool gauge for sharpening the various tools about the household is made of a block of wood with the sides of one end cut sloping in different degrees so that each will serve to secure the proper slant of the cutting edge on a certain tool.

The block of wood with the corners cut is shown in Fig. 1, and the manner of whetting a chisel is shown in Fig. 2.--Contributed by Will Parker, Wibaux, Mont.

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A cardboard cut the same size as a page and fastened
with paper clips in the center of a magazine will
prevent the pages from folding over when the magazine
is placed in a bookcase.

Submarine Photographs

A photographer at a seashore resort, wishing to increase his sales of souvenir postal cards, rigged up a device for producing negatives to make "submarine" pictures. The device consisted of an aquarium, about 40 in. long, 18 in. high and 6 in. wide. The aquarium was designed to stand on edge or the narrow way, and was equipped with rocks, living sea moss, kelp, and some fish, and the bottom was covered with sand and shells.

A canvas was hung back of the aquarium and the camera set in front at such a distance as to make a negative of only the water and the prepared sea bottom. Very fine views that will give the appearance of being made at the bottom of the sea can be produced.

Mending Paper-Pulp Utensils

Pails, washtubs, and other receptacles made of paper pulp, when cut and worn, may be easily mended with adhesive tape. After this is applied to the place to be mended, give the mended part a coating of paint, and when the paint has dried, the surface is given another coat to match the color of the article mended. Leaks may be entirely stopped in this way at a very reasonable cost.--Contributed by Katharine D. Morse, Syracuse, N. Y.

A Homemade Mailing Tube

A photograph or manuscript may be sent through the mail unmounted without the danger of being broken by placing it in a tube made as follows: For an 8 by 10-in. photograph procure a piece of cardboard 6 by 10 in., plain mounting board preferred, and cut halfway through the card in three places as shown by the dotted lines in Fig. 1. Then fold it in a triangular shape as shown in Fig. 2. It is easy to make such a tube to fit any photograph or manuscript to be mailed.--Contributed by A. H. Schaefer, Buffalo, N. Y.

Cutter for Lace Leather

Lace leather may be easily cut with an ordinary pocket knife having a U-shaped block fitted on the edge of the blade. The width of the opening should be exactly the same as the thickness of the leather and the width of the lace is determined by the distance between the blade and the depth of the notch. Several places can be provided for the blade to cut different widths of lacing.--Contributed by A. K. Runkle, Kinsman, O.

Refinishing Chairs

When refinishing chairs, a good way to get at the bottom part is to turn the chair upside down and place its seat on the seat of another chair. The legs and rungs can thus be easily cleaned and varnished.--Contributed by A. Mandeville, Ware, Mass.

An Electric Gas Lighter

A very simple and inexpensive electric gas-lighting device is shown in the accompanying illustration. The gas is ignited by means of an electric spark which is produced between the two parts A and B of an electric circuit. This circuit is composed of a source of electrical energy, such as a number of dry cells, a kick coil, the connecting leads, and a special operating switch for opening and closing the circuit to produce the spark. The circuit is normally open, but as the lever controlling the gas valve is moved from one position to the other, by pulling the chains, the lever C is caused to move through a certain arc. Now, as this lever C moves, its upper end passes the projecting point B, which is attached to the upper portion of the burner, and the electric circuit will be completed and broken. Just as the point A leaves contact with the point B an arc will be produced. This arc is greatly intensified by the kick coil, which acts as a sort of reservoir in which energy is stored while the circuit is closed, and upon opening the circuit this stored energy is given out by the kick coil and increases the size of the arc.

The points A and B should both be made of platinum, as other metals will not withstand the extremely high temperature of the arc. Pieces of platinum that will serve very nicely for the purpose may be obtained from an old incandescent lamp. The piece B is mounted on a brass collar, D, by means of a small screw, E. The brass collar D is held in place by the screw F, which draws the two ends together. This collar must be insulated from the stem or fixture by some thin sheets of mica. The upper end of the piece of platinum B should be just high enough to come within the lower edge of the gas flame.

Now mount an arm, C, on the valve stem so that it stands in a vertical position when the lever to which the chains are attached is in a horizontal position. Bend this arm into the form shown in the figure and cut its upper end off so that it is about 1/2 in. below the outwardly projecting end of the piece of platinum B. Drill a small hole in the upper end of C, and insert a piece of platinum and run some solder around it.

Then the complete burner and valve are mounted on the gas fixture, and from the collar D an insulated wire is run to the point where the battery and kick coil are to be located. The gas fixture itself is to form one side of the electric circuit, and one terminal of the battery should be connected to the gas pipe as shown in the figure.

A kick coil may be made as follows: Procure a small quantity of rather small soft-iron wire and cut a sufficient number of 8-in. lengths to make a bundle about 7/8 in. in diameter. From some good writing paper make a tube, 8 in. long and 7/8 in. in outside diameter. Use at least six layers of paper and glue the various layers together in forming this paper tube. After the tube has dried thoroughly, fill it with the pieces of iron wire until it is perfectly hard. Cut from some 1/2-in. hard wood, two pieces, 3 in. square, and drill a 7/8-in. hole in the center of each of these to a depth of 3/8 in. Now glue these pieces to the completed core and the winding can begin as soon as the glue is dry. Wind on this spool six layers of double cotton-covered No. 18 gauge wire, insulating the various layers from each other with several thicknesses of good writing paper. This coil is then mounted on a wooden base and suitable terminals provided.

At least four dry cells will be required to give satisfactory results. Bear in mind that the gas must be escaping from the burner when the arc is formed. The adjustment of the arm A, as given above, may result in the gas valve being closed when the arc is formed, and the device will then fail to operate. If this is the case, the arm C should be loosened and moved back so that the circuit is broken at a later time while the valve is being moved from the "off" to "on" position. The circuit should be closed for some little time before it is opened so that some energy may be stored in the kick coil. If the wire A is made long enough to project a short distance above B, it will result in the circuit being closed for a longer time than it would if they just touched.

Stretching Tight-Fitting Shoes

A tight-fitting shoe can be stretched by filling it tightly with oats dampened in water and packing some old paper in the top. The grain will quickly swell and, as the leather will get softened by the dampness, the shoe will be rapidly stretched. Allow time for the oats to dry out before removing them.--Contributed by Fred L. King, Islip, New York.

Pad for a Percolator

To prevent heating the bowl of a percolator and burning the handle, as often happens when it is placed on a stove, use an ordinary asbestos pad with a hole cut in the center as shown, just large enough to admit the foot of the percolator.--Contributed by Mrs. G. W. Coplin, Bay City, Mich.

* * * * *

If a motorcycle engine is raced while on the stand,
the cylinder will heat, often with the result that it
is ruined.

Compass Time Chart

A very instructive little instrument can be easily made for telling the time of any location on the globe. Its construction is extremely simple. Draw a circle, about 1-1/2 in. in diameter, on a piece of paper and then draw a larger circle, about 4 in. in diameter, around the first one. Divide the circles into 36 equal parts and draw lines from one circle to the other like the spokes in a wheel. These divisions will be 10 deg., or 40 minutes of time, apart. They should be numbered around the outside, commencing at a point marked 0 and marking the numbers by tens each way until they meet at 180 deg.

Using a map of the eastern and western hemispheres, write the names of the different cities on the globe in their respective degrees of longitude. The center, or inside, of the smaller circle is divided into 24 divisions representing the hours of the day and night, and these are marked from 1 to 12, the left side being forenoon, and the right, afternoon. The noon mark must be set on the line nearest to the location in which the instrument is to be used. For instance, if the instrument is to be used in Chicago, it is set as shown in the sketch.

The disk is mounted on a thin piece of board and a pin is driven through the center from the back side so as to make a projecting point on the upper side on which to place the magnetized needle of a compass. The needle may be taken from any cheap compass.

All that is necessary to do, to tell what time it is in any other city or country, is to turn the instrument so that the name of that place points toward the sun, when the north end of the compass needle will point on the disk to the time it is in that city or locality.--Contributed by Henry J. Marion, Pontiac, Mich.

Reversing Switch for Small Motors

A reversing switch made as follows will be found very serviceable in reversing the direction of the rotation of small motors, changing the polarity of electromagnets, etc.

A diagram of the connections to the switch and on the switch base is given in the sketch, and in this particular case the switch is shown connected to a small toy motor. The field of the motor is represented by A, the armature by B; and C, D, E, and F are four binding posts mounted on the base of the switch; G, H, and I are three contacts; J and K are terminals of the switch blades, and L a single-pole switch. The two blades of the reversing switch have their lower ends fastened to the terminals J and K, and their upper ends, which are indicated by arrow heads, may be moved over the contacts G, H, and I. For the position of the reversing switch shown by the full lines, J is connected to G and K to H. When the switch is thrown to the right-hand position, as shown by the dotted lines, J is connected to H and K to I. It is obvious that the direction of the current through the armature B will be reversed when the reversing switch is thrown from one position to the other. The direction in which the armature rotates will change, due to the reversal in direction of the current through it. The same results could be obtained by reversing the current in the field winding A. But it must always be borne in mind that in order to reverse the direction of rotation, the current must be reversed in the armature only or in the field only, not in both.

The above switch may be constructed as follows: First, procure a piece of well-seasoned hard wood, say maple, 1/2 in. thick, 2-1/2 in. wide and 4 in. long. Round off the corners and the edges of this piece on one side and drill the holes indicated in the sketch. The four corner holes should be of such a size as to accommodate the screws used in mounting four small back-connected binding posts. The remaining holes should be 1/8 in. All these holes should be countersunk with a 3/8-in. bit to a depth of 1/4 in. on the under side.

Cut from some 1/16-in. sheet brass two pieces, 2-3/4 in. long, 1/2 in. wide at one end and 1/4 in. at the other, and round their ends. Drill a 1/8-in. hole through the larger end of each of these pieces, 1/4 in. from the end, and also a hole through each, 1-1/4 in. from the narrow end. The last two holes should be threaded for 1/8-in. machine screws. Obtain five 1/8-in. brass bolts, 1/2 in. long. File the heads of three of these bolts down to a thickness of approximately 1/16 in. and mount them in the holes G, H and I. Before mounting anything on the base the grooves indicated by the heavy dotted lines should be cut in the under side so that the various points may be properly connected by conductors placed in the grooves. Now mount the two pieces of sheet brass upon the base by means of the remaining two bolts, which should pass through the holes J and K. A 1/16-in. washer should be placed between the pieces of brass and the wooden base.

Procure a piece of 1/8-in. fiber, 1-1/4 in. long and 3/8 in. broad. Drill two 1/8-in. holes in this piece, one in each end, so that they are 1 in. apart. Drill a third 1/8-in. hole in the center and fasten a small handle to the piece of fiber. Now mount this piece upon the two pieces of brass that form the blades of the switch by means of two small 1/8-in. brass machine screws.

Two small brads should be driven into the wooden base so as to prevent the possibility of the switch blades moving beyond their proper position. Two pieces of 1/16-in. fiber should be placed between the heads of the screws G and H, and H and I, to prevent the ends of the switch blades from dropping down on the wooden base.

Adjustable Rod for Potted Plants

Procure a brass sash-curtain rod of the telescoping kind and stick the solid part into the soil close to the plant and tie it to the rod. As the plant grows move the tubular part of the rod upward to correspond with the height of the plant. This makes a good support and is not so unsightly as a stick.--Contributed by Gertrude M. Bender, Utica, N. Y.

Wrench for Different-Size Nuts

A very handy wrench can be made from a piece of square bar, shaped as shown and fitted with a handle. The joint at A may be halved and riveted or a weld made as desired. The size of the bar and the space between the parts will depend on the size of nuts to be turned.

A Simple Sextant

A sextant for measuring the latitude of any place can be easily constructed as follows: While a board, 1 in. thick, 6 in. wide, and 12 in. long is about right for the instrument, any dimensions can be used, providing the line AB is at perfect right angles to the level of the sights C and D. The sights are better to use, although the upper edge of the board, if it is perfectly straight, will do as well. If it is desired to use sights, a slight groove is cut in the upper edge; a V-shaped piece, cut from tin, is fastened at one end, and a small pointed nail is driven in at the other. In doing this, be sure to level the bottom of the V-notch and nail point so that in drawing the line AB it will be at perfect right angles to a line between the sights. A tack is driven into the side of the board at the upper edge, a line fastened to it and a weight tied to the lower end which should swing below the lower edge of the board.

The instrument is placed in such a manner that the North Star is sighted, as shown, and the point on the lower edge of the board is marked where the line E comes to rest. A line is then drawn from A to the point marked and the angle F is measured with a protractor. The number of degrees in this angle will be approximately equal to the number of degrees in the latitude of that place.

The North Star is easily located by reason of its position relative to the Great Dipper, as shown by the diagram.--Contributed by Carlos Harrison, Anderson, Ind.

How to Make a Taper Ferrule

Having occasion to make a taper ferrule of irregular form, a pattern from which to cut the material was made as follows: A mandrel of the desired shape was made, a piece of writing paper, soaked in water, wrapped around the mandrel, and a piece of twine wound over it, coil after coil like the thread on a spool. This was allowed to dry thoroughly, using a little heat. The string was then removed and a longitudinal cut made in the paper while on the mandrel. When opened this paper formed the pattern.

A piece of metal was cut from the pattern and the edges were brought together and brazed with spelter. The point of the mandrel was driven through a piece of block tin, about 1/2 in. thick. The mandrel was then removed, the ferrule was placed on it, and both then started in the hole made in the tin and driven through it. As the mandrel with the ferrule passed through the tin, the metal was shaped exactly to the mandrel. It is best to oil the hole in the tin slightly. Tin is preferable as it is harder.--Contributed by James H. Beebee, Rochester, N. Y.

How to Make a Continuously Ringing Bell

The bell shown in the accompanying diagram is known as the continuously ringing type, and has quite a field of usefulness in connection with burglar alarms, door-bell signals, telephone signals, etc. The operation of the bell proper is identical with that of the ordinary vibrating bell and, in addition, there is a circuit controlled by the armature of the bell, which is normally open, but becomes closed as soon as the armature is drawn over. The closing of this circuit by the operation of the armature amounts to keeping the push button in the bell circuit depressed, and the bell will continue to ring until the latch A is restored by pulling the cord B.

Any ordinary vibrating bell may be converted into a continuously ringing bell as follows: In the armature, C, mount a short metal pin, D, and round off its under side slightly. A latch, A, should now be constructed similar to the one shown in the sketch and mounted in such a position that its left end will rest on the outer end of the pin D when the armature, C, of the bell is in its extreme outer position. The length of the latch should be such that its left end will drop off the end of the pin D, due to the action of the spring E, when the armature C is drawn over by the electromagnets F, thus allowing it to come into contact with a spring G, which is electrically connected to the terminal of the bell marked H. The latch A is connected to one side of the line, as shown in the sketch, so as to include the bell winding and battery in a local circuit that is formed by the latch coming in contact with the spring G. The end of the latch should not interfere with the free operation of the armature when it is resting on the spring G. A cord, B, attached to the outer end of the latch, is used in restoring it, and at the same time stopping the bell from ringing. The tension in the spring E should be so adjusted that the operation of the latch is sure and firm, yet not too stiff.

A Mission-Style Inkstand

Having a couple of good-sized ink bottles of the ordinary type lying around, I fashioned a mission-style stand for them out of a piece of yellow pine, 2 in. wide and 3 in. long, set on another piece of pine large enough to project all around on all four sides of the block, for a base. The wells were cut out with a wood chisel, and the parts fastened together with screws. The supports were four brass-head or upholsterer's tacks. The finish was flat black.--Contributed by James M. Kane, Doylestown, Pa.

Raising Dents in Wood

The imprint of a hammer on finely finished wood caused by a glancing blow, or otherwise, may be removed in the following manner: Pour enough wood alcohol on the dented spot to cover it, then light the alcohol and allow it to burn out. The heat will expand the wood and raise it enough so that the spot can be planed and smoothed in the usual manner.--Contributed by W. F. Elwell, Waltham, Massachusetts.

Carrying Two Pails in One Hand

When it is necessary to carry two small filled pails in one hand and a package in the other it will be found a very difficult job, if the contents are liquid. Procure a stick of sufficient size to carry the weight of the pails and cut a small notch in each end to admit the bail. Place a pail on each end of the stick and take hold in the center, or, if the pails are not equally filled, a little to one side of the center.

Preserving Paint in Open Cans

To keep paint from drying out in an open can it is necessary to exclude the air from the oil. This can be done by procuring an air-tight paper sack, which is tested by blowing into it. Set the can into the sack and tie it tightly with a cord. Mixed paint will be kept in a working state in this manner.

Jelly-Straining Stand

Procure a board, 7/8 in. thick and 18 in. square, and cut a hole, about 1 ft. diameter, in the center. Fasten posts, 4 ft. long, to each corner. Screw hooks are located around the edge of the hole to catch into the cloth used for holding the fruit. The stand is high enough to be convenient and admit a vessel beneath to catch the juice.

Renewing Dry Batteries

It is a well-known fact that dry cells commence to deteriorate from the time they are manufactured, and it is a matter of considerable uncertainty in purchasing cells to know whether they will continue to be efficient for their supposed natural life under the existing conditions of service, or for only a small part of this period. When the voltage of a dry cell falls below a certain value it is usually discarded and replaced by a new one, which often means quite an expense. The following simple suggestion will enable one to renew the prematurely exhausted cell with very little trouble and slight expense, so that its period of usefulness will be extended for a length of time, at least equal to that for which it could be used if put into service immediately after its manufacture.

The procedure in renewing the cell is as follows: A casing is placed outside of the zinc-containing case, having inside dimensions a little greater than the zinc cup. The space between the zinc cup and case is filled with a dry electrolyte, which, upon the addition of moisture, sets up a chemical action with the exterior surface of the zinc, and the latter having been perforated, causes electrical action to be again produced.

The casing, or cup, to be used outside the zinc cup should be made of a waterproof material. The electrolyte instead of being placed between this cup and the zinc in a powdered form, as might be expected, should be held by several layers of blotting paper, formed into a cylinder of the proper diameter to fit snugly on the outside of the zinc cup. This porous cup should be impregnated with a solution containing the following materials in the approximate amounts given: Muriate of ammonia, 10 parts; bichromate of potash, 4 parts, and chloride of sodium, 4 parts. After the porous cup has thoroughly soaked in the above solution it should be dried by passing a roller over its external surface when it is mounted on a wooden cylinder of proper diameter. The moisture-proof cup may be formed outside the porous cup by covering the latter with several coats of waterproofing paste and winding on several thicknesses of common manila paper, each layer of paper being treated with the paste. A disk of cardboard, properly treated, should be placed in the end of the cylinder to form the bottom, and the edge of the manila paper folded in over it and pasted in place.

The pasteboard covering surrounding the zinc cup of the cell should be removed and the surface of the zinc thoroughly cleaned. The coal tar in the top of the zinc cup should be removed by tapping around the edge with a hammer, and a large number of small holes should be made in the walls of the cup with a sharp instrument. Then put the cell within the porous cup and fill the top with clear water, preferably rain water. A chemical reaction will immediately take place between the outer surface of the zinc and the chemicals contained in the material forming the porous cup, and the terminal voltage of the cell will be practically the same as it was when the cell was new. The water, of course, must be replenished from time to time on account of evaporation, and the useful life of the cell can be prolonged for a considerable time. A part cross section of a cell treated as described above is shown in the accompanying sketch.

Workbench Equipment for a Table Top

The average home mechanic with a few tools seldom has a place to work and is usually without a workbench. As this was my case, I constructed a bench equipment that I could easily clamp to the kitchen or other table and thus have the necessary tools at hand for work. A plank, 2 in. thick, 10 in. wide and 18 in. long, was planed and smoothed up on all sides, and a vise and a bench pin were fastened on one edge.

To the under side of the same edge two blocks were securely fastened, as shown, and to these blocks two other pieces were fastened with hinges. With a bolt, running through from the top, and a thumb nut used underneath, these pieces are used as clamps for holding the bench to the table top. The top can be removed and set away in a closet when not in use.--Contributed by Wm. H. Hathaway, Nutley, N. J.

A Nonsticking Drawer Guide

The guide shown is nonbinding and has been found thoroughly practical after several years' use on furniture. The guide A consists of a piece of wood, about 1-1/8 in. square, with a concave cut in its upper edge, the width being about 3/4 in. and the depth such as not to cut through the extending end projecting over the crossbar B. The drawer sides have a half-round edge on the bottom edge to run in the groove in the guide. The difference in width between the groove in the guide and the rounding edge on the drawer side causes the drawer always to ride snugly without binding as the wood expands or contracts with changes in the weather.--Contributed by Herman Hermann, Portland, Ind.

A Milk Stool

The stool is made of three pieces of board and a piece of round, or stake, iron. The appearance and manner of construction are clearly shown in the illustration. The seat board is sawed out to fit the circumference of the bucket to be used, and the iron is also bent to this curve and fastened to the board as shown. The little shelf on the front support holds the bucket at the right height, and keeps it clean and out of the way of the cow's foot while milking.

Sounder for Wireless-Telegraph Messages

The owner of an amateur wireless outfit often has reason to regret that he cannot let some of his friends listen to a message at the same time as he himself. The magnifier described in the following permits all those present in the room to hear the message, provided, of course, they are able to interpret the Morse alphabet by sound.

A very simple means, making the message audible at a distance of about 10 ft., is to attach a phonograph horn, or a horn of cardboard or metal, to the telephone receiver, but a much better arrangement can be made as shown in the diagram, in which A represents the antenna or aerial; B, the detector, and C, the receiver. Procure a small microphone, D, placing its mouthpiece closely against the receiver--for the sake of clearness the two are separated in the diagram--and connect the former with a battery, F, of two or three dry cells, in series with the microphone of an ordinary telephone transmitter provided with a large horn. The effect obtained by this simple means will be surprising.

Joint for Mission Furniture

The mortise for this joint is made in the usual manner, the only requirements being that the mortise is run through the piece, and the tenon is cut 1/8 in. shorter than the depth of the mortise or the width of the piece it is entering. The end of the tenon and the mortise is then covered with a piece of metal, fastened with screws as shown. The metal can be of any desired material and beveled on the edges. This makes a very good knock-down joint for mission furniture.--Contributed by H. R. Allen, Cheyenne, Wyoming.

A Towel Roller

A substantial, convenient and nonrusting towel roller can be made from 8 or 9 of the familiar wood handles on bundle carriers and a length of brass curtain rod. The bracket ends can be shaped from any piece of wood of suitable dimensions. The rollers and ends can be finished as desired.--Contributed by F. E. S., E. Lynn, Mass.

An Electric Shaving Mug

The general use of electricity in the home has opened up a new field in the way of heating and cooking utensils. While these utensils are sold by electric-supply houses, some of them can be easily made at home and answer the purpose just as nicely. One of these is the electric shaving mug.

A mug that will stand heat is the first thing required, and an aluminum cup of standard shape and design, which can be bought in almost every town, will do perfectly well. These cups are spun from a flat sheet and have no seams to open and leak, and it is necessary that no holes be drilled in the cup as it is impossible to make such a hole watertight. The heating element must be fastened to the mug with a clamp. The clamp will also allow the heating coil to be removed for repairs without injury to the mug. The bottoms of these mugs have a flange which makes a recessed part and in this the heating element is placed.

The legs of the mug are made of sheet brass as shown in Fig. 1, one of the three having an enlargement near its center with a hole for an insulating button (Fig. 2), of "transite" or some other material, to hold the supply cord in place.

The clamp for holding the heating coil in place is shown in Fig. 3. This clamp has a screw in the center to tighten it in place. The legs and clamp may be nickelplated if desired.

The heating coil is shown in Fig. 4 which is a coil of flat "Nichrome" wire, or ribbon as it is called, 12 ft. long, 1/16 in. wide and 3/1000 in. thick. This is equal in cross section to a No. 26 gauge wire. To wind this coil, procure a block of wood, 7/8 in. thick and about 4 in. square, with a 1/2-in. hole in the center for an axis or pivot. Clamp a 1/2-in. rod in a vise so that the block can be rotated about it. Begin at the center and fasten one end of the ribbon to the block, leaving about 2 in. projecting for a connection, then proceed to wind the ribbon in a spiral coil, separating each turn from the preceding one with a strand of asbestos cord. A small section of the coil is shown in Fig. 5, in which A, or the light part, represents the asbestos insulation, and B, or the black lines, the heating element. The insulation may be obtained by untwisting some 1/8-in. round asbestos packing and using one of the strands. This cord insulates each turn of the ribbon from the other and the current must travel through the whole coil without jumping across from one turn to the other. The whole coil must be closely wound to get it into the limited space at the bottom of the mug.

Before taking the coil from the block, rub into its surface a little asbestos retort cement, or a cement composed of a mixture of silicate of soda and silica, or glass sand. This mixture, when dry, will tend to hold the coil together and the current may be passed through the coil to test it as well as to bake it in its coiled shape.