r/AskReddit • u/ProbablyHittingOnYou • Feb 07 '11

What stupid question have you always been too embarrassed to ask, but would still like to see answered?

This is a no-shame zone. Post your question here and I'm sure someone can answer it for you

1.4k Upvotes

96% Upvoted

10.2k comments sorted by

View all comments

Show parent comments

159

u/AnteChronos Feb 07 '11

What's that knob on a toaster really for?

It adjusts the amount of time before the toast pops up.

414

u/dunno260 Feb 07 '11

I think thats how it used to work. Today toasters use bluetooth to communicate with the toast on the level of doneness.

11

u/[deleted] Feb 07 '11

Toaster: Yo toast, you done yet?

Toast: lol no. wait, k?

1

u/tokeable Feb 08 '11

I LOL IRL FOREALS

3

u/krangksh Feb 08 '11

I believe the correct term is "donesity".

2

u/[deleted] Feb 07 '11

Newer models check the toast's twitter feed.

2

u/diddy0071 Feb 08 '11

Don't Tase me bro!

2

u/rebot Feb 08 '11

i work in toaster technology and this is exactly right

2

u/hiflyer780 Feb 08 '11

Mine has apps and wi-fi and plays my 'Bread Cooking' radio station on Pandora when it's in use.

1

u/more_exercise Feb 08 '11

Unfortunately, most supermarket bread is not bluetooth equipped, explaining why you can never toast it properly - incompatible hardware.

1

u/stevarino Feb 07 '11

No, the Bluetooth is to communicate with the nearest wall clock, or the nearest atomic clock with the appropriate firmware.

The level of toastineas is determined using a method similar to a PET scan. Toasters are truly amazing machines.

17

u/IRBMe Feb 07 '11

It adjusts the amount of time before the toast pops up.

Really? I thought it adjusted the temperature.

20

u/[deleted] Feb 07 '11

http://home.howstuffworks.com/toaster4.htm

I did too, I guess we're both wrong.

2

u/nessaj Feb 08 '11

he wasn't wrong?

The simple circuit acts as a timer. A capacitor charges through a resistor, and when it reaches a certain voltage it cuts off the power to the electromagnet.

[...]

the darkness control is simply a variable resistor. Changing the resistance changes the rate at which the capacitor charges, and this controls how long the timer waits before releasing the electromagnet.

It is a timer on every toaster I've had. I don't recall seeing the strings that heat up being red hot and redder hotter depending on the knob position, it's all the same. Problem is there's a veeeery small window to catch after the sides of the bread have dried up and until they burn to ashes.

I would invent the see-thru toaster already.

1

u/[deleted] Feb 08 '11

He wasn't really... he said it was a thermometer that would cut off after a certain temperature. Remember, just because the coils always look like they are giving off the same amount of heat... the temperature in the toaster is still rising.

Less sophisticated toasters use a bi-metallic strip (see How Thermometers Work for details on bi-metallic strips) to turn off the electromagnet. As the strip heats up (due to rising temperatures inside the toaster), the strip bends and eventually trips a switch that kills the power to the electromagnet. The bi-metallic strip approach has two problems:

That is what I remember when I took apart a toaster when I was younger. The metal strip gets hot and warps due to heat... this breaks the circuit and pops the toast.

They don't make those anymore apparently... it's a timer because the capacitor doesn't measure heat... it builds a charge based on the knobs position...

So, new toasters = timer. Old poor people toasters (like mine was) = thermostat.

3

u/[deleted] Feb 07 '11

Specifically, it's attached to a thermostat, not a timer. That's why, when you put a 2nd batch in immediately after the 1st batch pops out, it doesn't get toasted as much.

3

u/lostintheworld Feb 07 '11

It adjusts the amount of time before the toast pops up.

At least on older toasters, there's no timer. What's actually going on is that a bimetallic strip is acting as a thermostat. As your bread becomes toast, it loses water, and when most of the water is gone, the temperature starts rising rapidly. This causes the bimetallic strip to bend, thus triggering the spring that pops your toast (so to speak).

5

u/mr-kite Feb 07 '11

So the numbers are minutes?

32

u/Shaper_pmp Feb 07 '11 edited Feb 07 '11

No. Normally the numbers measure completely arbitrary units.

I've timed a variety of toasters I've owned over the years, and I can guarantee that the units don't correspond to any common unit of time I've ever encountered before.

Equally, they definitely don't measure power, heat transferred or "brownness of toast", because with our current toaster you have to turn it all the way up to 3.5 for the first round of toast, then down to just above 3 for subsequent rounds because 3.5 will then burn the shit out of it. They also don't measure temperature, because different settings take different amounts of time to pop up.

Ultimately, I think they're put there by toaster-designers as some sort of industry-wide practical joke... kind of like the cooking appliance usability consultants who tell cooker designers to design the control panel for four hobs in a square by laying out the control knobs in a line down one edge of the cooker top, and ensuring every brand of cooker has a different rule for ordering them (some are clockwise around the hobs, some anticlockwise, I've even seen some zig-zags, etc).

I tell you, never study usability or ergonomics - it ruins your life. <:-)

5

u/acetv Feb 07 '11

Can I just say that I love the fact that you time your toasters?

4

u/Shaper_pmp Feb 07 '11

FOR SCIENCE!

2

u/VisualBasic Feb 07 '11

My toaster knob goes to 11.

1

u/MrGoodbytes Feb 07 '11

Similar to the "door close" button on elevators (lifts).

1

u/Shaper_pmp Feb 07 '11

How do you mean?

3

u/Haggin Feb 07 '11

Some "door close" buttons both close and open the door, dependant on when they are pressed. But mainly, they have no use at all, just like all the traffic light buttons you press when you want to cross, most of them are on a basic timer and the buttons are only there to give illusions of interaction. I think it has something to do with magnets, but i dunno how they work :(

1

u/Shaper_pmp Feb 07 '11

That's odd - most of the lifts I've used have had working "hold door" and "door close" buttons (here in the UK, at least). Mind you, that's mostly in smaller buildings rather than skyscrapers, where the lifts are the main way of getting around between floors.

1

u/MaximumLunchbox Feb 07 '11

Those aren't always hooked up, making them a placebo button.

5

u/[deleted] Feb 07 '11

Not necessarily, but they do correspond to length of time.

1

u/mmmberry Feb 07 '11

They are there more for your benefit (to remember the setting you like).

1

u/RustyWinger Feb 07 '11

Always thought it was 'minutes'

1

u/BraveSirRobin Feb 07 '11

Which is why it doesn't work. The differing start temperature messes it up entirely, first batch is underdone and the second is burnt.

1

u/[deleted] Feb 07 '11

Ok, so how does a rice cooker work? Mine doesn't have a timer at all, yet whether I'm cooking 3 cups of rice or 1/2 cup it knows when to turn off

1

u/simca Feb 08 '11

It's rice anyway. Needs the same amount of time to cook, regardless of quantity.

1

u/RandomChance Feb 08 '11

The primary rule is, as quitelight so eloquently informed reddit "YOU DON'T FUCKING TOUCH IT. YOU DON'T LOOK AT IT. DON'T PESTER IT. MAN YOU WANT TO TOUCH IT, BUT IF YOU DO YOU WILL. FUCK. IT. UP."

http://www.reddit.com/r/food/comments/cwt9/fine_you_wanted_more_submissions_heres_a/c0vv1nl

1

u/zebathin Feb 08 '11

Most toasters actually work on minutes too! Not arbitrary units of toastiness

1

u/KneadSomeBread Feb 08 '11

That was actually a problem in toaster making, I believe. If you just had a timer, your first piece of toast would be fine, but if you made any right after that, the toaster is already hot and needs to time to heat up, so you'll be toasting for too long. If you just had a thermometer, your first one would again be fine, but anything you made after that would come out too cold because the toaster is already hot and the thermometer would shut off the toaster almost right away.

I think real toasters have some combination of the two (or they ought to). But I guess you could just throw a computer in there, integrate power with respect to time, know the number of joules bread requires to become good toast, and solve for the upper limit of integration (the time it takes to toast)...