# Popular Mechanics/Volume 49/Issue 1/How to Build a Dumb-Waiter

Layout 2
How to Build a Dumb-Waiter
By ERIC B. ROBERTS
Amateur knowledge of carpentry is all that is necessary to build the dumb-waiter described in this article and shown in the illustrations. The first step is to choose a location where a vertical drop to the basement will meet with no obstructions. After the location has been determined, the shaft is built from the ceiling of the first story to the basement floor. The frame of the shaft consists of 2 by 4-in. material; in the kitchen this is boxed in with 1-in. stock on the inside and lathed on the outside preparatory to plastering. If desired, wallboard can be used on the outside. The basement section of the shaft is also boarded up tightly. A neat paneled door should be provided for the kitchen outlet of the waiter, but a simple board door will suffice in the basement. A wooden floor is provided at the bottom of the shaft and four holes are drilled in the floor to hold old auto-valve springs in a vertical position to absorb the shock of the lift when it is lowered rapidly.
After the shaft has been finished, the rails or guides for the lift are fastened on the inside, leaving out a short section to permit the insertion of the lift, after which the omitted guide section also may be fastened in place. Lengths of $^3$⁄$_4$-in. wood may be used for making the guides. Next, the lift should be made. For the average household it should weigh about 65 lb., so that it will carry a load of from 5 to 20 lb. The counterweight, which consists of scrap lead, iron, etc., must be between 5 and 10 lb. heavier than the empty waiter, to allow for the additional load. To obtain the above-mentioned weights, ​placed the materials used for making the lift on one end of a plank, pivoted in the center, to balance the counterweight on the other end. When both weights were equal, I added about 8 lb. to the counterweight. Then I proceeded to build the lift, which was made with double sides, top and bottom in order to make it solid and heavy. Ordinary 1 by 6-in. lumber was used. Angle iron may be used to add weight and rigidity but it must be rememhered that no additional material must be used besides that which was balanced with the counterweight. Between the two boards forming the side, a groove is left for the guide, on each side. The pulley assembly is then made. It must be carefully calculated where the ropes and weights are to hang in order to be sure that they clear the lift while in motion or at rest, and the weight must be hung in a position where it can do no damage if it falls. The pulleys need be of no special size; anything from 2 to 7 or 8 in. will do. They must, however, be of the grooved type and able to retain a $^3$⁄$_8$-in. rope. Lengths of pipe or rod make good axles. I used one 2-in. and two 4-in. pulleys, the rope passing over the large ones and under the small one to provide the necessary friction to hold the waiter steady at the top or bottom, yet allow it to move freely when pulled up or let down. Ordinary sash cord is well suited for use in a dumb-waiter.
Constructional Details of the Dumb-Waiter, Showing the Shaft, Lift and the Counterweight, and the Method of Assembly
Copper Pipe Aids in Coiling Wire
Coiling wire for springs, electrical coils or for binding purposes, is accomplished usually with some means to restrain the wire and keep it under tension. Leather and wood will serve for holding the wire under tension while it is fed on a lathe mandrel at a slow speed. A new means, differing from any of the customary practices, is shown in the attached drawing, and consists of a short length of small copper pipe, with abrupt bends, which restrains the wire and maintains sufficient friction to insure tightly wound coils, in spite of the fact that the operation is rapid and the wire tension uniform.
Renovating Copper-Asbestos Gaskets
When the cylinder head of a car is removed for valve grinding and carbon removal, the gasket is frequently bent, dented or otherwise mutilated. Efforts to straighten it are not often successful, because the copper is usually brittle and hardened from use. This is also the case with the copper-asbestos gaskets used for the water connections, manifolds and valve seats. If installed with sharp bends and kinks in them, they are almost certain to leak. To renew the old gaskets, they are placed in the flame of a gas heater until they are quite red and then plunged in cold water. The copper is made plastic by this treatment, and, when the gasket is bolted down, it spreads and makes a tight seal.
Vulcanizing Inner Tubes
In vulcanizing small patches on inner tubes with an electric or gasoline vulcanizer, a Wisconsin repairman claims that the portion of the tube covered by the patch is apt to become overcooked or burned, and thereby weakened. To overcome this trouble, he uses four strips of asbestos paper over the tube. as shown in the illustration, leaving only the patch exposed to the full heat of the vulcanizing plate.
Small Crane for the Garage
Small Portable Crane for the Garage Has Several Features of Convenience and, Besides, Requires Little Floor Space
The crane shown in the accompanying drawing has a wide range of travel and is capable of transferring heavy units from the bench to the machines and to the several cars being repaired. It uses the same track as employed to support the hanging doors at the front of the garage. The provision of such a track around the four walls, is the main support for the crane. A double hanger with swivel rollers allows the crane to travel along the continuous runway. The corners are traversed on a curved track, similar to the track on which the door is supported when swung from the front to the side. A cross rail extends from these hangers and rests on a vertical support of pipe, provided with a fixed roller at the bottom. The hoist is carried by a trolley on the cross rail, which permits placing the hoist directly above the load. While every advantage of a crane is provided, the single leg, reaching to the floor, does not encroach on the available floor space, as is usually the case with four-legged portable cranes.
Unscrewing Thin Tubing
When unscrewing thin tubing, there is a decided tendency for it to close under the wrench grip, especially at the open ends. To prevent damaging the pipe, the method of protecting it shown in the illustration, has been found effective. It consists in screwing a pipe cap on the end of the pipe and gripping it as close to the cap as possible. Also in the removal of close nipples, this procedure is useful. The cap stiffens the nipple so that it can be removed easily, regardless of the tendency of the pipe-joint compound to hold it tight.—G. A. Luers, Washington, District of Columbia.
Better Potato Plants
By placing a 4-in. layer of sawdust on top of his hotbed. a Mississippi farmer produced potato plants with much longer roots than usual, which made them more desirable than short-rooted plants. In making the hotbed, he first dug a hole to a depth of about 12 in. In the bottom of this he placed a 6-in. layer of barnyard manure, covering it with a layer of soil about 5 or 6 in. thick. On top of this he placed the potatoes to be sprouted, pressing them into the earth and covering them with a thin layer of soil. A 4-in. layer of sawdust was then applied. Some 6-in. planks, held in position by stakes, prevented the sawdust from being washed away. This hotbed was not covered with glass. Besides producing long roots on potato plants, the sawdust helps to retain moisture. Potatoes should not come in contact with manure because the latter is likely to transmit certain diseases to the former, causing the potatoes produced to be defective.―Bunyan Kennedy, McCool, Mississippi.
How to Mend Aluminum with Zinc
Holes in aluminum vessels can be mended by the following method: Paste a piece of strong paper over the hole on the inside, using shellac as an adhesive. Have the surface of the aluminum very clean by sandpapering it well. Pack the vessel with sand to hold the paper in position securely. Now take some clean zinc, melt it, clean off all the dross and pour the zinc over the hole from the outside. It will stick to aluminum, and can be finished with a file and sandpaper. We have mended canteens, hot-water bottles, kettles, pans, etc., by this simple method. If you wish to solder anything to aluminum, first coat the aluminum with melted zinc poured on, then solder to the zinc surface, using common solder and a good flux.―Robert C. Knox, Santa Barbara, Calif.
Saw Case for the Tool Chest
A number of saws are generally carried in a well-equipped tool chest, and protection for the teeth is not always easy to provide. One carpenter uses a novel saw holder, which occupies little space and holds several blades for the detachable handle. Separate cases are used for miter and other attached-handle and backed saws. Such holders are made of pieces of prepared roofing, such as comes in rolls, using a kind which does not contain crushed stone or anything injurious to the saw teeth. After cutting and forming it to the shape of the saw, a few turns of friction tape hold everything firmly. and the case may be tossed into the tool chest without risk of damaging the saws.
Restoring Contact of Third Generator Brush
When the third brush on a Ford generator is shifted to change the output, it sometimes fails to make good contact with the commutator and there is no output at all. This is often caused by a little dirt or an uneven surface on the brush. The proper method is to sand the brush to fit, but if the brush is pressed down gently with a small stick while the motor is running slowly, it can often be made to "run itself in" and the generator will charge.
Fitting Lathe to Do Job That Requires Larger Swing
Boring Auto Wheels on Lathe Which Is Too Small to Handle Them in the Regular Way
The photos show how a job of boring automobile wheels to fit the hubs was done by fitting a faceplate to the back end of the lathe spindle. The faceplate was mounted on a shaft extending through the hollow spindle and was fastened in place by means of a nut and washer. The wheels were centered by means of a tapered cone, which was mounted on a stub mandrel screwed into the opening in the center of the faceplate after the wheel was lightly fastened with bolts and clamping pieces, as indicated. The cone was then removed and the boring done by means of a tool consisting of a suitable guide piece screwed into the faceplate opening, the guide carrying a sliding member with an adjustable cutter and an operating handle.
Easily Built Portable Coal Bin
Portable Bin Which Can Be Taken Down When Not Needed for Coal Storage
Many home owners have only small basements and during the months when no coal is used, a bin is not needed, unless it is filled during the summer for the following winter. A portable coal bin of the kind shown in the drawing can readily be built by anyone. It can be taken down when not in use and put up again when coal is to be taken in. It is constructed of 1-in. boards which are slipped into grooves formed by nailing strips to 2 by 4-in. uprights. These extend from the floor to the joists above, to which they are bolted with 1/2-in. bolts. The boards are slipped into the grooves near the top and are forced down tightly. These boards should not be over 4 or 5 ft. long, unless an extra 2 by 4-in. upright is provided on the outside as a brace.
Etching on Aluminum
Etching on sheet aluminum is made better and more simple by using a solution of weak hydrochloric acid. It is important that this acid be diluted and not used in its full strength, for in a diluted state it will produce better work.