I have one of these (kindly given to me along with a few other things by Chipps for some work I did for him last year)…

I like to drink hot beverages (I’m a heathen, I’ll admit, I don’t drink coffee I’m a tea man!) out of it once in a while, but I’m puzzled… Why on earth does my hot beverage cool down much faster in this particular mug than in any other? It’s a bit of a double edged sword, cos as I can drink it quicker than I might do otherwise, I’m kinda used to making a cup of tea last 20 minutes…

The mug is the heaviest mug I’ve ever felt, so I’m thinking that it has something to do with sheer mass of material in the mug acting as a massive heatsink, but I didn’t think ceramics were supposed to be a good conductor of heat? Or have I got my pre GCSE materials science mixed up?

Anyway, thanks in advance for helping with my random question!

Coffee mugs are often pretty thick, the idea is you warm them up before you put the coffee in, that’s why in coffee shops the mugs sit on top of the machine

Is it wider at the top than your normal mug? More heat loss though onvection than conduction?

I have no idea though so I”m just guessing….
😀

it has something to do with sheer mass of material in the mug acting as a massive heatsink

yes.

I didn’t think ceramics were supposed to be a good conductor of heat?

there not.

http://en.wikipedia.org/wiki/Thermal_conductivity

http://en.wikipedia.org/wiki/Heat_capacity

difference between these two properties may help.

I didn’t think ceramics were supposed to be a good conductor of heat?

If that was true you wouldn’t need a handle on your mug.

I have often wondered the same, but no idea why it goes cold so quickly. Also interested in answer.

If that was true you wouldn’t need a handle on your mug.

So pray tell, why do they cover the Space Shuttle in Ceramic tiles to stop the bloody thing burning up on re-entry eh? I’d say given that my mug is about 1/4″ thick material for the most part, and when I fill it with water at 100 degrees C and I can actually hold the outside of the mug quite comfortably without using the handle, that’s poor conductivity in my book.

Thank you thomthumb, that was the answer I was looking for… 😀

It’s black so absorbs more heat. HTH.

So pray tell, why do they cover the Space Shuttle in Ceramic tiles to stop the bloody thing burning up on re-entry eh? I’d say given that my mug is about 1/4″ thick material for the most part, and when I fill it with water at 100 degrees C and I can actually hold the outside of the mug quite comfortably without using the handle, that’s poor conductivity in my book.

I didn’t say it was a good conductor, just that it does conduct heat, as anyone can tell just by holding a cup of tea.

Definitely dark blue cougar…

Anyway, in the interests of science, just made myself another cup of tea. Less than 2 minutes from pouring boiling hot water into the cup, I’m able to swig fair mouthfuls of tea. Only a small amount of milk added too. With most mugs, being the heat sensitive little blighter I am, I’d normally be waiting the best part of 10 minutes to be able to start swigging mouthfuls!

I didn’t say it was a good conductor, just that it does conduct heat, as anyone can tell just by holding a cup of tea.

Anything conducts heat to an extent. But a stainless steel mug would be far hotter to the touch than a ceramic one.

What’s the contact patch to the desk like? The same as other mugs? The heat has to be going somewhere if it’s cooling down faster. Also surface finish. Is one mug smoother then the other? This could affect heat transfer to the air.

What’s the contact patch to the desk like? The same as other mugs?

Without getting a vernier caliper out, I’d say it’s pretty similar

Surface finish is very similar too. I’m pretty sure it’s explained by what thomthumb said above, combined with the blurb on the website stating it’s about twice the weight of a normal mug so it’s essentially acting as an enormous heatsink.

Darker colours also radiate heat more than paler colours.

Tea in a coffee mug. Mug is trying to repulse the tea.

Maybe your kettle is broken.

Maybe your kettle is broken.

Definitely not. This is the 3rd kettle the mug has been used with, other (thinner) mugs always take a lot longer for the tea to cool down in.

Tea in a coffee mug. Mug is trying to repulse the tea.

Was another possibility… Sadly the only coffee I can even bear to drink a cup of (and even then once in a blue moon) is super cheap, and freeze dried. I’m just not a coffee man!

At the same time as you pour the boiling water into the teapot, also fill the mug with water. Empty the mug just before you pout the tea from the pot.

You are making tea in a pot, right?

this thread is proper dull

Sorry miketually, I’ve been doing it the builder’s way (tea bag in mug), all by myself though I might add…

I’ll have my Butler make it the “proper” way, in a pot, and get the fine china out next time eh! 😕

😉

Definitely sunspots.

I’m convinced that’s the reason anyway that everything of mine seems to have broken this week.

this thread is proper dull

Meh

Depends on your point of view… For me, it’s insightful to know why I have to drink my (badly made, in a coffee mug) cup of tea quicker than normal cos it cools down so quickly.

Besides, I’ve read some of your posts in the past… Or sorry, I tried to, but fell asleep part way through! 😉

My dad is a potter and has theories on this subject. He has spent 40 years in the pursuit of making the drinking and serving of hot beverages a beautiful thing, ( hes quite famous in the ceramic world) I’ll ask him next time I see him!

Because whenever you look the other way someone is weeing in your tea

The milk will be having an affect on it…try the same experiment without the milk…

No doubt DickBarton, but I’ve never not drank it without milk in, even just a small amount. This mug definitely cools everything down VERY quickly.

So pray tell, why do they cover the Space Shuttle in Ceramic tiles to stop the bloody thing burning up on re-entry eh?

The tiles on the shuttle are sort of airated/foamed ceramic, the trapped air provides the insulation, the ceramic is used for its doesn’t-melt properties. Although I like the idea of using regular bathroom tiles, perhaps something a bit ornate, maybe a few brass fittings – a sort of victorian public baths aesthetic.

“I like to drink hot beverages (I’m a heathen, I’ll admit, I don’t drink coffee I’m a tea man!) out of it once in a while, but I’m puzzled… Why on earth does my hot beverage cool down much faster in this particular mug than in any other? It’s a bit of a double edged sword, cos as I can drink it quicker than I might do otherwise, I’m kinda used to making a cup of tea last 20 minutes…

The mug is the heaviest mug I’ve ever felt, so I’m thinking that it has something to do with sheer mass of material in the mug acting as a massive heatsink, but I didn’t think ceramics were supposed to be a good conductor of heat? Or have I got my pre GCSE materials science mixed up?

Anyway, thanks in advance for helping with my random question! “

What do you believe to be ‘random’ about your question?

What do you believe to be ‘random’ about your question?

He picked it out of a hat 🙂

I have the older cream coloured version of that mug. For best results it does need to be pre warmed, if I can be bothered I fill it with boiling water and let it stand for a minute or so before pouring out the water and making a drink.

Although it is a handy mug if you want to drink a hot drink quickly.

My Denby Large Jet Curve Mug is better … 😆

I do the really hot water over the mug thing too. I also get paranoid about a wee spoon draining the heat away from it so I never leave it in there ;O)

Sad,useless facts that probably don’t make one bit of difference.. but I do it anyway.

I do the really hot water over the mug thing too. I also get paranoid about a wee spoon draining the heat away from it so I never leave it in there ;O)

Sad,useless facts that probably don’t make one bit of difference.. but I do it anyway.

Anyway, in the interests of science, just made myself another cup of tea. Less than 2 minutes from pouring boiling hot water into the cup, I’m able to swig fair mouthfuls of tea

You need some super-slim built Royal Albert! I can drink tea from a cup 15 mins later and burn ma tongue. Well,not quite but a lot longer than 2 mins!

There was a long thread a couple of years ago about exactly this issue with the ‘old’ huge ST coffee mug. There was a sciencey word for it, but it is basically to do with how chunky it is and how more of the heat of the drink goes away on warming up the greater mass of the chunkier mug. I have thin ‘tea’ mugs that keep coffee warm much longer than thicker ‘coffee’ mugs.

Best things to do are to have it black (white coffee is nice enough, just less ‘coffee-ish’), and to drink the first one really quickly then have a second one straight away. 😀

hhmmm … my Denby mug seem to be ok to retain the heat. It’s heavy (quality) but not so thick.

Alternatively how about … Tatonka Expedition Mug? 😆

Just seen this…

Do you make sure that the mug is piping hot before putting your drink into it? That’s the secret. Otherwise the cold mug will suck the heat out of your drink. Pour some hot water into the mug beforehand, let the mug heat up and then the mug should help keep the hot drink hotter for longer.

why do they cover the Space Shuttle in Ceramic tiles to stop the bloody thing burning up on re-entry eh?

Ceramic is just a type of material, not anything specific. From wiki:

“A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling.”

So glass would be a ceramic also. It’s like saying ‘metal’ or ‘crystal’ or something.

If your mug is similarly proportioned but twice the weight of a normal mug I’d wager it is composed differently either physically or chemically, or perhaps both.

Re the spoon – it doesn’t remove much heat from the tea I don’t think but it does get really hot if you leave it in, thus making it harder to remove without pain.

The biggest issue I see with that mug design is the shape. From a lot of personal mug research (I have many) I can conclude that that shape of outer wall causes easier spillage than a concave wall. Much more spillage. however the spillage rate then increases again as you get really concave walls. About the inverse of that wall shape is ideal for spillage control.

As mentioned above, the reason heavy mugs cool drinks faster is higher specific heat capacity (generally) of more dense materials and more material to heat. It’s only when the mug has thoroughly equalised in temperature through it’s thickness that the convection from the outer surface begins to make any real effect (and that time to equalise is based on the thermal conductivity of the material as well as the specific heat cap).

IME the spoon has a fairly large effect on heat loss, especially if you use a large spoon or fork. I hate hot drinks being too hot and often use spanners and screwdrivers in the garage to cool it down before drinking, again their mass and Cp mean just lobbing them in cools it nicely in minutes.

Put the mug in a microwave (if you have one available) for 1.5 minutes whilst the kettle is boiling (based on an 800w microwave) and you should have a mug that’s hot enough to help your tea retain heat for longer whilst not being too hot to burn your hand.

You could also put a small saucer over the top of your mug which should help to retain the heat for longer. (once the boiling water has been put in obviously)

Put the mug in a microwave (if you have one available) for 1.5 minutes whilst the kettle is boiling (based on an 800w microwave) and you should have a mug that’s hot enough to help your tea retention heat for longer whilst not being too hot to burn your hand.

You could also put a small saucer over the top of your mug which should help to retain the heat for longer. (once the boiling water has been put in obviously)

Not a great idea to microwave items with no moisture content, best to put water in it first.