The Magic Clock Hand
The hand, or pointer, is the only working part needed to perform the trick. A clockface can be drawn on any piece of white paper, and a pin stuck in its center on which the hand revolves. The hand A is cut from a piece of sheet brass, and may be in any form or design desired, but it must balance perfectly on the axle, which passes through a ¹⁄₄-in. hole in the center, or else the magic part will fail. The illustration shows a good design with dimensions that will cause it to balance well; however, this can be adjusted by removing some metal from the end that is heavier with a file or tinner’s snips, or a bit of solder may be stuck to the lighter end.
Design of a Hand That will Balance Well and the Parts for Its Axle
A disk, B, is cut from a piece of sheet brass, 1¹⁄₈ in. in diameter, twelve ³⁄₃₂-in. holes are drilled at equal distance apart near the edge, and a ¹⁄₄-in. hole is drilled in its center. This disk is soldered to the hand where both ¹⁄₄-in. holes will coincide. It is necessary to procure two washers, C and D, that are embossed, or raised, in the center, and about 1¹⁄₄ in. in diameter. These can be purchased from a dealer in curtain rods, the rod parts wanted being the washers used on the ends. A careful mechanic can raise the center portion of a brass disk by beating it over a hole with a ball-peen hammer.
One of the washers, C, has a spring, E, soldered at one end, and the other carries a small projection that will engage the holes in the disk, B. The projection can be made by driving the metal out with a center punch, set on the opposite side.
The washer D is provided with a lead weight, F, and a ¹⁄₄-in. stud, G, is soldered in the center. The stud has a ¹⁄₁₆-in. hole drilled through its center for the pin axle. The weight is made by filling the washer with melted lead, which when cold is removed and sawn in two. One piece is then stuck in the washer with shellac. The stud is ⁷⁄₈ in. long with the upper part, about ¹⁄₄ in. in length, filed, or turned down, smaller, and threaded. Just below the thread, or on the shoulder, the body is filed square to fit a square hole filed in the face washer C carrying the spring. This square hole and stud end are necessary in order that both washers may turn together.
A Number is Mentioned and the Performer Gives the Washers a Twist to Set the Concealed Weight so That the Hand When Hung on the Dial will be Drawn to Point Out the Number Selected
The dial can be made of a piece of thick cardboard, or thin wood, with the numbers from 1 to 12 painted on, like a clockface. A pin, ¹⁄₁₆ in. in diameter, or an ordinary large pin, is run through the center so that it will project on the face side on which the hand is to revolve.
The washer D with the weight is placed on the rear side of the hand with the fixed stud run through the hole in the center of the hand; then the washer C is placed on the square part of the stud, and the nut J, which should have a round, knurled edge, is turned on the threads. This will cause the projection on the spring E to engage one of the small holes on the disk B. In turning the two washers, C and D, with the thumb and first finger of the right hand, the projection snapping into the holes of the disk B can be felt. The hand is placed on the pin of the clockface, and the washers are turned so that the weight will make it point to 12. Scratch a mark on the hand at H, also mark a line on the front washer at this point. These lines are necessary, as they enable the performer to know how many holes to snap the spring over to have the hand point at any desired number.
By reversing the hand it will point to a different number; for instance, if set for 8 and put on the pin backward, it will point to 4, and so on, with other settings. The dial can be held in the hand, hung on a stand, or fastened to a wall, and can be used to tell the day of the week, time of day, cards selected, etc. The audience can call for any number on the clockface, and the setting of the disks is an easy matter while holding the hand, or pointer, in the hands, so that it cannot be detected.