Tesco have a special offer on the Thermos Work flask. Half price for a limited period. At £12 these are a bargain.
http://direct.tesco.com/q/R.100-8295.aspx
http://direct.tesco.com/q/R.100-8295.aspx
The Vacuum Flask Test
- Thread starter MagiKelly
- Start date
SimonM
Bushcrafter (boy, I've got a lot to say!)
I've had the same flask now since I was an apprentice, so thats 22 or so years. It is an Aladdin Stanley, and if memory serves correctly is made to the same design and spec that US WWII bomber crews were issued with.
It has seen service on building sites across the country, 12 years or so service with the TA / Cadets and countless days out on the hills, and bears the scars and dents to prove it!
It is not the lightest of flasks, but still keeps my coffee hot till the end of the day, so is still my flask of choice, despite having a couple of lighter, Tatonka models.
Simon
It has seen service on building sites across the country, 12 years or so service with the TA / Cadets and countless days out on the hills, and bears the scars and dents to prove it!
It is not the lightest of flasks, but still keeps my coffee hot till the end of the day, so is still my flask of choice, despite having a couple of lighter, Tatonka models.
Simon
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Thanks for the interesting review. I've also often wondered if the old glass flasks perform better than the stainless ones. I no longer have any glass ones to test my theory on as they all broke.
I wonder if there's an ultimate top of the range flask. I like the convenience of a half litre flask for carrying around but I have noticed that by the middle of the day it's not as hot as my larger flask.
There is also a large difference in prices. You can pick them up for a couple of quid in some stores like Poundstretcher or pay around £20 more for branded ones in more expensive shops.
I wonder if the 0.5 litre Thermos on special offer at Tesco right now performs better than my cheap one that does manage to keep the water hot enough for a coffee at lunchtime. The Work Thermos does come out well in your tests but it is also bulky for carrying around. The extra performance might be due to the thicker wall.
I don't have a great knowledge of physics but I presume heat retention in a vacuum flask is largely due to how well the lid creates a vacuum and reduces heat loss. There is also the problem of radiative heat loss. Glass flasks were much more shiny inside so I presume this is an advantage in heat retention over the dull interiors of stainless flasks.
The weak link in modern flasks seems to be the lid, especially the ones that pour without opening as they tend to break and allow heat to escape.
Hmm, maybe I should become a Thermos geek.
I wonder if there's an ultimate top of the range flask. I like the convenience of a half litre flask for carrying around but I have noticed that by the middle of the day it's not as hot as my larger flask.
There is also a large difference in prices. You can pick them up for a couple of quid in some stores like Poundstretcher or pay around £20 more for branded ones in more expensive shops.
I wonder if the 0.5 litre Thermos on special offer at Tesco right now performs better than my cheap one that does manage to keep the water hot enough for a coffee at lunchtime. The Work Thermos does come out well in your tests but it is also bulky for carrying around. The extra performance might be due to the thicker wall.
I don't have a great knowledge of physics but I presume heat retention in a vacuum flask is largely due to how well the lid creates a vacuum and reduces heat loss. There is also the problem of radiative heat loss. Glass flasks were much more shiny inside so I presume this is an advantage in heat retention over the dull interiors of stainless flasks.
The weak link in modern flasks seems to be the lid, especially the ones that pour without opening as they tend to break and allow heat to escape.
Hmm, maybe I should become a Thermos geek.
Interesting review. Has anyone tried out the Tatonka vacuum flasks? My only reason for asking is that they came out top in a recent(ish) review in "Trail" magazine.
SimonM
Bushcrafter (boy, I've got a lot to say!)
Hi Tiley,
i have the Tatonka 1l steel flask, and it does what it says on the tin - veery good flask IMHO.
As I stated in my post tho, I prefer to use my Aladdin Stanley, mainly becasue we have "history" and I'm a big softy at heart!
Simon
i have the Tatonka 1l steel flask, and it does what it says on the tin - veery good flask IMHO.
As I stated in my post tho, I prefer to use my Aladdin Stanley, mainly becasue we have "history" and I'm a big softy at heart!
Simon
I've got one of those aladdin stanley flasks, I got it years ago in a NAAFI in cyprus with a couple of insulated mugs.
cracking piece of kit.
cracking piece of kit.
Okay I did a quick test on an unbranded 0.5 litre vacuum flask. I've had this one for five or six years. I can't remember where I bought it or when or how much it cost but my guess is it was on special offer in some kind of store like Wilkinsons or Poundstretcher. I reckon it was less than a fiver, probably around three quid.
It has a mechanism that you push down in the lid to pour water and then you push an outer ring and it locks back. This mechanism looks fragile and when I bought it I thought it would only last a few months but it has lasted years.
For my test I thought I should clean out the limescale and when I did it looked a lot nicer inside. I poured boiled water from an electric kettle into the room temperature flask. I took a thermometer reading of the water I'd just poured in (I used a food thermometer so the readings aren't very precise) and the temperature was 95C (not 100C).
Four hours later (this would have been about the amount of time until my coffee break) the temperature had dropped from 95C to 76C - not quite hot enough to properly brew my fresh ground coffee really (so that's what's been wrong with my coffee breaks ).
I tested the temperature again 81/2 hours later (should have been 8 hours but I forgot) and the temperature had dropped a mere 57C.
It has a mechanism that you push down in the lid to pour water and then you push an outer ring and it locks back. This mechanism looks fragile and when I bought it I thought it would only last a few months but it has lasted years.
For my test I thought I should clean out the limescale and when I did it looked a lot nicer inside. I poured boiled water from an electric kettle into the room temperature flask. I took a thermometer reading of the water I'd just poured in (I used a food thermometer so the readings aren't very precise) and the temperature was 95C (not 100C).
Four hours later (this would have been about the amount of time until my coffee break) the temperature had dropped from 95C to 76C - not quite hot enough to properly brew my fresh ground coffee really (so that's what's been wrong with my coffee breaks
).I tested the temperature again 81/2 hours later (should have been 8 hours but I forgot) and the temperature had dropped a mere 57C.
i have found that for longer trips out only keep water in your flask...
it reduces staining and tainting and you get to start from home with a pre-heated flask containing boiled water.......
At every opertunity use the boiling water from the flask in your billy to make your brew. Top this up with cold when reboiling for the brew so that you can refill your flask with boiling water again.
This ensures you have a full flask at all times and you use less fuel when making a brew as your stating water is hot.
It leaves you with a flaskful of hot water at all times and has the bonus of taking less time to brew up on the stove/fire.
it reduces staining and tainting and you get to start from home with a pre-heated flask containing boiled water.......
At every opertunity use the boiling water from the flask in your billy to make your brew. Top this up with cold when reboiling for the brew so that you can refill your flask with boiling water again.
This ensures you have a full flask at all times and you use less fuel when making a brew as your stating water is hot.
It leaves you with a flaskful of hot water at all times and has the bonus of taking less time to brew up on the stove/fire.
