Really Retro!
How to Make an Electric Toaster (1921)
There is no toast superior to that made by the even heat of an electric toaster, and as such a toaster is of simple construction, anyone having 110-volt alternating or direct current available should not be without one.
The base is cut from a piece of sheet metal, to the form and dimensions given, and bent down along the dotted lines until the gaps at the corners are closed, the edges then being soldered. Four supports like those indicated, to hold the heating elements, should also be provided. These supports, which may be made of any convenient metal, or, better still, of fiber, are attached to the base with screws. A hacksaw cut in the upper end serves to receive the mica sheets, while a tapped hole at right angles to the slit is provided with a setscrew, or machine screw, to prevent the heating units from shifting their position.
The support on which the latticework bread rack is mounted has an opening cut in the center before it is bent into the form shown, and is either soldered or riveted to the base. The rack that supports the bread and holds the upper ends of the heat units in position, is made of six strips of sheet metal, 1/4by 11 in., bent as shown. These six pieces are equally spaced and held together by horizontal strips at top and bottom; the rivets used being made from pieces of copper, or other soft wire.
The heating units consist of resistance wire wound over mica supports, each unit being wound with 36 turns of .015-inch German-silver resistance wire, wound directly on the mica. Each mica sheet is 2 by 4 1/2 inches. The winding should start at the bottom of the left unit and pass over the top of the right and down to the bottom, the actual winding being done before the units are put into place. The elements are then set into the slotted supports provided on the base, taking care that the supports, if these are of metal, do not short-circuit the units, and the setscrews, if such are used, are tightened until the mica is held rigidly. If machine screws are used, holes of ample clearance should be drilled through the mica to accommodate them. The upper ends are held in position by passing two pieces of copper wire through holes in the mica, above the resistance winding, and twisting the ends around the upper parts of the metal crosspieces. Two knots of fine wire are then wrapped around this wire on each side and against the mica plate, and a drop of solder is used to hold them.
The terminals of the winding are joined with solder with pieces of asbestos or rubber insulated wire of about No. 18 gauge, which is passed through the holes in the base and out one end, or through holes in the lattice support. It is permissible to solder these connections, as No. 18 wire is so much larger than the resistance wire that the joint does not reach a temperature that would melt the solder, although the remainder of the unit stays at a dull-red heat. The loose ends of the wire passing through the base should be joined to a suitable cord extension and attachment plug for connecting the device to the lamp socket. The metal parts may be nickeled if a neater finish is desired.
Popular Mechanics, 1921