The Antique Toaster that's Better

By the time this video is over, you’re gonna to be mad at your toaster. This is a Sunbeam Radiant Control toaster. It’s pretty old. One might say, quite old. This particular toaster was most likely made in the early 1960’s, but its design goes back at least to 1948. But don’t let its age fool you, in most respects, this chrome contraption is light years ahead of your toaster.

Unless you have one of these in your kitchen, you’ve never known true toasting luxury. Let me show you what I mean. To use this modern, fancy pants toaster, you must first place your bread into the slots, then firmly press down on this lever. Then you must wait. Once the timer reaches zero, your toast is thrust upward with passionate fury, and you may now enjoy your toast. Now, to use this practically antique toaster, you begin by inserting your bread slices into the slots and then… 

Did that... the bread. It just went down on its own. What madness is this? Oh, but this is an old fashioned toaster. It doesn’t have that digital display to warn me that the toast is gonna pop up. Wait, did it just shut off?

*stares intensely as bread rises*

(in a slow whisper) What is happening?

Now, if you’re like me, you’re not just flabbergasted by this toaster’s effortless, silent, and fluid operation; you’re also mad at how clunky and obnoxious this much, much newer toaster is. Let’s go for another round of toast. Literally the only thing you have to do with this toaster, assuming you’ve set the darkness where you want it, is place the bread in the slots. It does the rest, and in style. This is how all toasters should work! 

Before we get too deep into this toaster, you might want to check out a video I quite recently made about the electromagnet in your toaster. There is a beautiful elegance to the way modern toasters operate, and it was in making that video that I was reminded of these 20th century marvels. You’ll of course find a link to that video in the description, or you can click the card up above. Let’s start with aesthetics. If you don’t find this toaster to be downright beautiful, then frankly you don’t deserve its operational perfection. The polished chrome is such a beautiful finish, and it’s been crafted into a timeless shape. The right hand toast slot is marked “One Slice”, as this slot contains both the actuator lever to start the toast cycle, as well as the thermostat.

Backlight handles on either side enable you to move the toaster when it’s hot, and the darkness control is hidden under the right hand handle. On the bottom you’ll find the crumb tray, as well as the various patents Sunbeam was most proud to be the holder of. Other than that, it’s just a pretty toaster. Really the only radically different thing about this is its lack of a lever. But of course, that’s what’s so neat. So let’s take a closer look at the toasting action. Looking down into the slots reveals the fact that the right-hand side contains a lever that the bread falls on. This actuates the switch which starts the toast cycle. Once it’s started, the bread immediately descends into the toaster, and the heating elements begin to glow.

Notice how the heating elements are different in the center vs. the sides. Both heating element styles are necessary for this toaster to function as intended, but we’ll get back to that. Once the toast cycle is complete, you hear a click, the heating elements switch off, and the bread is slowly lifted back up. This toaster is clever in more ways than one. Not only is it Automatic Beyond Belief! it’s also using a very crafty thermostat design. Modern toasters operate based on a timer, either using a logic chip or a more rudimentary circuit. Older toasters, like this, use a bimetallic thermostat to end the toast cycle. But the way Sunbeam has used it here makes for a very consistent toasting experience. If I activate the toaster by pushing the lever down with a high-tech insulated poking device, you’ll see the bread lifters fall, and the heating elements glow. But the toaster barely runs before shutting off.

Why is that?

Well, the reason the heating elements are so different on the sides versus the middle, is to allow the thermostat to “see” the bread. The bimetallic strip lives right between these two heating coils, and it’s shielded from their heat output by these little wings. When it’s toasting, the bimetallic strip isn’t warmed significantly by the heating elements; instead it’s warmed mainly by the heat radiating from the bread itself. This means that, effectively, it measures the surface temperature of the bread in order to determine how done it is. That’s where the toaster gets its name. Radiant control.

By pointing the thermostat at the bread, it’s able to consistently trip at the same relative darkness, pretty much regardless of how hot the toaster itself is. Here, I’ll let the patent speak for itself: The principle of operation of the control mechanism is based upon the fact that the surface of a bread slice emits a definite amount of radiant heat per unit area of surface when brought to a preselected temperature and on the fact that within the limits of permissible error a preselected temperature at the bread surface will always correspond to a certain brownness thereof.

For example, it appears that with bread of normal composition practically no visible chemical change occurs in the surface of a slice subjected to temperatures below about 350 °F. However, as the temperature approaches 500 degrees, chemical changes occur at an increasing rate. Time and the rate of heat input are also factors in the degree of chemical change produced, but the temperature factor has been found to be so critical under the conditions prevailing in an ordinary bread toaster as to make the other two factors of negligible importance. Thus when the bread surface, during the toasting operation, reaches a predetermined color, the heat emission therefrom will always be substantially the same, and this radiation or emission may be used for the purpose of actuating a control mechanism.

The reason why the toaster barely ran when I started a toast cycle with the pen was that without bread in it, radiation from the center elements can travel straight into the thermostat’s “eye”. It is shielded at the start of a toast cycle by this little plate which falls as the bread does, but once it’s exposed to the heat coming from the middle elements, it will quickly trip and stop the toast cycle.

 OK, so we know why the side elements are made from two coils. So the thermostat’s “eye” can sit between them. But why, then, isn’t the center element the same? Why is it made of this thin wire? Well, that wire, believe it or not, is what lowers the bread into the toaster. The entire mechanism is based around the thermal expansion properties of the nichrome wire heating element. To better understand this, we need to take this apart. And, through the magic of buying two of them, I have an already-taken-apart one right here!

With the rather ugly innards exposed, one of the first things you’ll notice is this wild series of levers and linkages. These two arms form a third class lever, and connect to the bread lifters through a linkage on the right hand side. The fulcrum of the lever is at the extreme left. When the toaster is engaged, the arms swing downward and thus bring the bread into the toasting position. It’s a little hard to see what makes them fall, but watch closely.

 The force in our third class lever is applied right here, and due to the nature of third class levers, the amount of motion imparted by the force is greatly multiplied, however the strength of the force is greatly reduced. This doesn’t much matter, though, as we’re just lifting a couple slices of bread. The force on our third class lever is itself derived from the action of this first class lever, with the fulcrum here in the center, and the input force coming from right here. Now here’s where things gets pretty clever. Mind blowingly clever, if I do say so myself. The input side of that lever is connected to this crossbar, which is connected via a set screw to the central core of the toaster. It’s a little hard to see, and I’d rather not remove it for fear of breaking the toaster, so here’s the image from the patent application.

The part we want to focus on is here. The nichrome wire is wrapped many times around two vertical structures, which are attached to each other via these flexible linkages at the top and bottom. The nichrome wire is wrapped quite tightly, so this entire thing is under tension. The squeezing force causes the two sides to be pulled closer together, which flexes the top and bottom pieces, and slightly increases the central core’s overall vertical length. This is how the toaster sits in its resting state. When a piece of bread is inserted, the force of the bread falling on the trip lever flexes the bimetallic strip via this linkage, and engages the switch contacts. With power flowing through the heating wire, it rapidly heats up, which causes it to expand ever so slightly.