Proper ferrofluids

Friday 12th August 2016

After last week's disaster, here's a short video showing how Ferrofluids are supposed to look! I gave up trying to make my own and bought some from eBay along with some extra-strong neodymium magnets.



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Copper refining part 2

Friday 10th June 2016

Last Friday I finally got around to melting down a bunch of old scrap copper that I'd had lying around for months. I've now got enough copper and tin to cast my bronze sword!

My technique has really come on since I built my bucket furnace. I borrowed a friend's leaf blower for the air induction and it's way better than Kat's old hairdryer.

I've discovered that it works much better with real charcoal than charcoal briquettes, which leave a lot of claggy residue in the furnace and stop it getting hot enough.

Here's a quick video showing the refining of the scrap copper into pretty little ingots. It takes about two hours to get hot enough to melt the copper at 1084 °C, but then it's so hot that it melts down the next batch in a couple of minutes.

The molten copper is indescribably beautiful and quite took my breath away. It's a pale shimmery metallic salmon colour with a strong orange glow. I think I'm a little bit in love with it. I watched a Youtube video of a guy pouring gold a while ago, he said that after you see your first pour the metal takes up a little piece of your heart forever. I think I know what he means. 

At the end of the video are the wooden model sword that I carved, and a test aluminium version that I cast last year. Can't wait to cast the bronze one!



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Lamb's pluck

Friday 15th April 2016

A little while ago I bought a lamb's pluck from my local butchers - a liver, lungs and heart attached. I wanted the heart for some photos of my heart post, but I thought you might like to see, hear and taste the rest of the organs!

Not for the squeamish, but I guess you've worked that out already.

Are you a big fan of lungs? Let me know a good recipe in the comments.



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Teaching the dog to count

Friday 1st April 2016

Over the last few months I've been teaching our dog Stanley to count. I'm a big fan of Chinese dog trainer Huj Ly Ur and her amazing work getting dogs to drive, skate, and of course count.  

Here's a video of Stanley's progress.


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Cooking with insects

Friday 25th March 2016

Ever since I was a kid, people have touted insects as the future of food. In some parts of the world they already are - I lost count of the number of times we saw various insects in markets in SE Asia, including this delicious sight in Skoun, Cambodia, where fried spiders are the local delicacy. No, I didn't try them.

You're eating insects

Even westerners eat a surprising amount of insects every year. The FDA's Defect Levels Handbook details exactly how many insect fragments is too many:

  • chocolate - over 60 insect fragments per 100g
  • curry - over 100 insect fragments per 25g
  • macaroni - over 225 insect fragments per 225g
  • wheat flour - over 75 insect fragments per 50g


Cricket flour

But from an environmental point of view, we should all be eating insects. It takes something like 4,000L of water to make a kilo of beef, but just 2L of water to make kilo of cricket flour as well as massively lower methane emissions.

So when a wonderful friend, Celia, was kind enough to give me a bag of cricket flour, I thought I'd give it a go. The 100g bag she gave me contains around a thousand milled crickets. By weight it has twice as much protein as beef, the same amount of calcium as milk, and as much vitamin B12 as salmon.

I tried some of the flour raw, it doesn't really taste of anything. I grew up with a lot of lizards that ate crickets, so I'm very familiar with the smell of them. Unsurprisingly the flour smells just like crickets, slightly nutty and not at all unpleasant.

Here's my recipe for cricket ginger nuts:


Makes 30

  • 170g plain wheat flour
  • 80g cricket flour
  • ½ tsp bicarbonate of soda
  • 1 tbsp ground ginger
  • ½ tsp mixed spice
  • 125g unsalted butter
  • 185g soft brown sugar
  • 60ml boiling water
  • 1 tbsp golden syrup

Here are the finished item - for comparison I made a batch on the left which use just wheat flour, and the cricket cookies on the right.


Preheat the oven to 180ºC / 160ºC fan.

Sift the wheat flour, cricket flour, bicarbonate of soda, ginger and spice into a bowl.

You may want to sift the cricket flour last and keep an eye out for large fragments like this one, which is about 3mm across. Discard them if you're a bit squeamish.

Add the butter and sugar, and rub together with your fingertips until the mixture resembles fine breadcrumbs.

Pour the boiling water into a small jug and add the golden syrup.

Stir until mixed, and then add to the flour mixture. Stir with a knife until the ingredients are all mixed.

The mixture will be very wet and sticky.

Form into small balls and place on a couple of greased baking trays.

Bake in the oven for about 15 mins. They'll be very dark, so don't rely on being able to tell visually when they're cooked or you might burn them.

Place on wire racks to cool, and them film your friends eating them.



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Friday 11th March 2016

Lock picking has been on my list of skills to learn for years, but I just discovered how easy it is to buy picks on the web. Check out this short video that I made about it.

Here are some links to the picks and locks in the video:

It's really made me realise how poor padlocks are at security. The last lock in the video was used for several years to secure about £10,000 of film club equipment, but I can open it in under a minute without any fuss.

If you're interested in learning this I'll happily lend you my picks, but I'd be careful where you take them. Once forum post I read said that the police in the UK take a pretty dim view of people out on the street with a set of picks. You'd need a pretty good reason to have them, otherwise you're probably going to get arrested.

While learning to pick locks, I've seen a lot of information about locksport - competitive lock opening. There's a really big community in the UK, and their core message, which I've seen over and over is that you can only pick locks that you own, and never pick a lock that's in use. The second one is really important - a couple of times I've broken locks while picking them, and you wouldn't want to do that to your front door!



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Happy Christmas

Friday 25th December 2015

Happy Christmas from Lost In Thought!

This looks best full screen.

This is 45 hours of time-lapse photography compressed into a minute and a half. We used three of these magic snowmen from eBay (I love eBay), which work in the same way as those crystal trees that were so popular when I  was a kid.

It's a saturated solution of potassium phosphate, which is drawn up into the paper snowman and then forms crystals as the water evaporates from the snowman's extremities.

See you in the new year!



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Drink driving

Friday 28th August 2015

Having previously said I don't drink, I'm going to see how drunk I can get and still be under the UK alcohol limit. I decided it was a teeny bit unethical to get behind the wheel, so I'm going to test myself on GTA V instead.

I created a simple course that mimics my everyday life. So I'm going to drive from my luxury penthouse apartment to the clothes shop for a new dress, then go for a haircut before driving to the golf course.

But first, Science™. Or if science isn't your thing, just skip to the heading marked Sober.


Blood alcohol concentration

When a bottle says that it's 5% or 40% alcohol, that's the amount of the liquid in the bottle which is pure ethanol, the stuff that gets you drunk. So a pint (568mL) of Carlsberg Export at 5% is 28.4mL of ethanol (568 * 5 / 100).

In the UK we use a system called units to make it easier to keep track of what you've drunk. One unit is 10mL of ethanol. So a pint of Carlsberg Export is 2.84 units (28.4 / 10), although it just says 2.8 on the can to avoid confusing drunk people.

Still with me?

Drink drive limits are expressed as the amount of ethanol in a certain amount of blood, or breath. The UK drink drive limit is currently 80mg of ethanol per 100mL of blood (or 35 μg per 100mL of breath). 80mg/100mL is more commonly expressed as 0.08 BAC (Blood Alcohol Concentration).

But how much do I need to drink to stay below that?


The Widmark method

The generally accepted method for calculating blood alcohol is the Widmark method, which is gives the blood alcohol concentration in g%:

BAC = (0.8 * ethanol in mL * 100) / (weight in Kg * 1000 * gender constant)

The gender constant is 0.68 for men and 0.55 for women and relates to the different amounts of water in the bodies of men and women. Re-arranging this to give me the most I can drink and still be below the UK drink drive limit gives me a wonderfully simple formula:

Ethanol in mL = weight in Kg * gender constant

For me, this is 47.6mL ethanol, which is 4.76 UK units. This is just over a pint and half of Export, or four shots of gin, which is what I'm going to drink.

I know before I even open the bottle that I'm going to be utterly incapable of driving anywhere.



First, I need a benchmark, so I drove the course sober in 5 minutes and 39 seconds.


Drunk in the game

If you've played GTA V, you'll know that there are all sorts of ways to get high in the game. As an extra benchmark I wanted to get plastered in the game (still sober in real life) and then drive the same course to see what time I get. The vehicle swerves all over the road after you've had a few and is very hard to control.

The main problem here is that you can't shop or get a haircut while the police are after you, and drink-driving catches their attention pretty quickly.

It didn't end well and no matter how many times I tried, I couldn't get to the golf club without dying. Here's an example.


Drunk in real life

To be honest I wasn't looking forward to this, it's definitely one of the worse ideas I've had lately. But here goes.

I drank four shots of gin and a pint of tonic water in ten minutes and then tried to play the game. I got round the course in 7 minutes 12 seconds, but I found it hard to navigate the menus and failed to buy a dress or get a haircut.

There's no way I should be driving in real life. My driving wasn't that bad, I could control the car much easier than being drunk in the game, but I found it very hard to concentrate on playing and keeping the truck on the road. I guess this is why we have drink-drive laws! Apologies for the mumbly, slurred commentary in the video.


Want to give it a go?



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Copper refining

Friday 21st August 2015

I've just had my first go at copper refining from some old scrap copper pipe, and it's really really hot.

I've been playing with aluminium up to now which melts at a balmy 660 °C, easily achievable with my furnace. Copper melts at 1084 °C which makes it glow bright yellow!

Here's a quick video of my first attempt at copper.


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Friday 14th August 2015

I'm a massive Nutella fan, so when a friend posted a link explaining how to make it, I ran right out to buy some hazelnuts. I wanted to avoid using palm oil, and thought it would be extra awesome with coconut oil instead. I made a batch with normal oil, a batch with coconut oil and a batch with dark chocolate just to see what would happen.

Here's a quick video showing what I did:


Update: I've since discovered a much simpler version if you're in a hurry - see the end of the post for details.

  • 170g hazelnuts
  • 340g chocolate - milk or plain depending on what you like
  • 45ml coconut oil (or vegetable oil if you prefer)
  • 3 tbsp icing sugar
  • 1 tbsp cocoa powder
  • ½ tsp vanilla essence
  • ½ tsp salt


Heat your oven to 160°C (non-fan oven 180°C) and bake the hazelnuts for 10-12 minutes until they brown slightly.

Microwave the chocolate until it's just liquid and then stir to make it smooth.

When the hazelnuts are done, rub the skins off with a tea towel, leave them to cool down and then puree in a blender for about 5-10 minutes until they become smooth and buttery. If they're very fresh nuts, you may want to roast them for a bit longer, otherwise the water in them is going to react with the chocolate to form a solid mess.

Add all the remaining ingredients and continue to blend for another few minutes, until the mixture is smooth.

Strain through a sieve to remove the larger chunks (there will be some small pieces left in the mixture) and then scoff it all straight out of the bowl immediately.



Since I wrote this post I've refined the ingredient and made it much simpler, here's an updated recipe:

  • 170g smooth hazel butter (like Biona)
  • 340g chocolate - milk or plain depending on what you like
  • 3tbsp coconut oil

Melt the chocolate in a microwave and then mix all the ingredients together. Done!

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Ice cream vans in games

Friday 12th June 2015

Ice cream vans and video games are inseparable. Here's a quick run-down of the history, thanks to YouTube:


Twisted Metal - Playstation 1 (1995)   

I believe this is the earliest use of an ice cream van in a game. As far as I can tell, the van had no music. It was driven by a killer clown called Sweet Tooth.


Micro Machines 3 - Playstation 1 (1997)   

The ice cream van featured in the track Breakfast at Cherry's, great game but sadly no music.


Carmageddon 2 (1998)   

Finally, some music! Another appearance of Sweet Tooth.


Grand Theft Auto 2 - Playstation 1 (1999)   

For me, this was the one that started it all. It's the first use of an ice cream van in the GTA series, with a short but catchy tune.


GTA 3 - Playstation 2 (2001)   

This is a classic. The van is called Mr. Whoopee and features a single ice cream swirl and a chocolate bar on the roof. The van is slow with bad steering, but that's not why you're driving it. In the mission "I Scream, You Scream" you use the van to lure your opponents to their doom.   


Tony Hawks Pro Skater 3 - Playstation 2 (2001)   

A bit of a weird, snub-nosed ice cream van, but it features good strong tune so we'll let it go.


GTA Vice City - Playstation 2 (2002)   

The return of the Mr Whoopee van, but with ice cream breasts and cherry nips! It features the same tune as in GTA 3, which is slightly disappointing. The "Distribution" mission has you selling drugs to pedestrians.


GTA San Andreas - Playstation 2 (2004)   

GTA rules when it comes to ice cream vans. San Andreas saw the return of the truck, named Mr Whoopee sporting a giant willy and new tunes.


GTA 4 - Playstation 3 (2008)   

GTA 4 marked a new, more serious era for the series. Gone are the genitals, although it has several different tunes and the faster you drive, the faster the tempo of the music. It still has terrible acceleration and top speed.


GTA V - PS3 / PS4 (2014)   

Sadly, GTA V doesn't feature an ice cream van at all! It's been replaced by a Taco van which doesn't have a jingle. It's a sad day for ice cream lovers in Los Santos.


WatchDogs - PS4 (2014)   

It looks like Watchdogs has taken the ice cream crown from the GTA series, with a lovely van and nice music.

Today I'm starting an official campaign to make Rockstar Games include ice cream vans in the next version of GTA. I hope I can count on your support.



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Making soap

Friday 5th June 2015

I've wanted to try this ever since I saw Fight Club! I've seen several methods for making soap, but I'm always attracted to using dangerous chemicals, so lye seemed the obvious way to go.

Lye, sodium hydroxide, is an incredibly caustic chemical with a bad boy reputation for removing fingerprints and dissolving corpses. During the second world war, Leonarda Cianciulli liquidised three victims in Italy using the stuff, and Santiago Meza López, "The Stewmaker", claims to have disposed of 300 bodies with it. 

I decided to make a floral lavender soap and a macho coffee soap inspired by The Art of Manliness. They say that coffee soap is very good for cleaning harsh smells from your hands.

I used The Sage to get the right quantities of oil, water and lye, and off I went!


Lavender soap

  • 1 litre (916g) of olive oil
  • 286ml cold water
  • 115g lye crystals
  • 20g ground lavender
  • 20g lavender flowers
  • 10ml lavender essential oil
  • Food colouring (optional)

Coffee soap

  • 1 litre (916g) of olive oil
  • 136ml cold water
  • 115g lye crystals
  • 3 double espressos (totalling 150ml)
  • 1/2 cup of coffee grounds


You'll also need:

  • Eye protection, a face mask and gloves - I can't overstate how dangerous lye is
  • 1 litre of vinegar - in case you spill lye on yourself you'll need to neutralise it really quickly
  • Thermometer
  • Bowls and stirring tools that aren't aluminium or wood - lye will eat through these
  • A stick blender - it reduces the stirring time from an hour to 5-10 minutes
  • Moulds to pour the soap into - I used four old takeaway containers with lids
  • Towels to wrap the moulds

The pictures are all from the lavender soap, but it's the same process for making the coffee version. 


First you'll need to make the lye solution. Put on all your protective gear. Mixing lye with water is extremely exothermic, and so it's really important to add the lye crystals to the water and not the other way around! If you're making the coffee version, wait for the espressos too cool, then mix with the water. Make sure you've got 286ml of liquid in total.

Do this outside as the fumes are really nasty, and add the crystals bit by bit, stirring continually. By the time I'd added all the lye, the water had jumped from 10°C to 95°C. You really don't want it to boil.

Now you need that to cool down to 50°C maximum, so leave it outside and heat the oil to about 50°C as well. Once the lye has cooled, pour it gently into the oil and gently mix together. Add the ground lavender and the lavender oil, plus the colour if you're using it, then blend with the stick blender for 5-10 minutes until it's the consistency of thick custard.

Pour some of the lavender flowers into the bottom of the moulds, then add the gloopy soap, seal the moulds and wrap in towels to keep the heat in. Leave for 24 hours for the soap to set.

The next day, pop the soap out of the moulds, cut them up and leave to cure for 6-8 weeks. This allows all the lye to react with all the oil to make soap, called saponification.

Here's a short video I made of the process:

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Mentos eruption

Friday 29th May 2015

I've seen some great Mentos and Diet Coke eruption videos on Youtube, and I've always wondered whether other soft drinks work too.

Here comes the science.


The Mentos eruption works just as well with any kind of soft drink, but it doesn't work with Fruit Mentos or sparkling water. It will be more explosive with powdered Mentos because of the increased surface area.


12 bottles of various soft drinks and 12 packets of Mentos were bought from a local supermarket. The bottles were opened and a packet of Mentos (eight sweets) was dropped into the bottle using our patented delivery mechanism (an empty Berocca tube).


Screenshots were taken from the video at peak foam. The images were scaled to make the bottles the same size and the eruptions were plotted on a pretty graph.

The average heights of the eruptions were calculated. Note that Coke Life and sparkling water were not included in either of the diet or regular averages.

  • Average height: 26cm
  • Average diet drink height: 26cm
  • Average sugary drink height: 34cm
  • Average Tesco drink height: 32cm
  • Average Coca-Cola drink height: 28cm


Our experiment shows that soft drinks containing sugar can produce higher eruptions than diet products, and that it does work with Fruit Mentos but not with sparkling water. Powdered Mentos do not produce a higher plume than whole sweets.

Sadly our delivery mechanism left a lot to be desired, and to be honest the height of the eruption a lot to do with how many Mentos were delivered into the bottle before it started foaming.

Wikipedia explains the science behind it. The world record for the most number of simultaneous Mentos and Soda fountains is 4,334 bottles at once!

Thanks very much to my awesome cameramen Jay-yoh and K-Herb.



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Metal casting furnace

Friday 15th May 2015

My aim this year is to cast my own bronze sword, and to do that I need to melt the bronze. I just made a bucket furnace that's good enough to melt copper and tin, the metals in bronze alloy. My furnace is based on the Mini Metal Foundry on Youtube.


Here are ingredients to make it.

  • 10 litre metal bucket - the body of the furnace
  • 5 litre plastic bucket - to make a void in the centre of the furnace
  • 15 litre plastic bucket - to make a lid for the furnace
  • Tin can - to  make a void in the centre of the lid, to release pressure
  • Two metal hoops - these will become handles for the lid
  • 1 inch steel pipe - this is the air intake for the furnace
  • 25kg dense castable from Castree Kilns
  • dog - serves no useful purpose


Making the lid

First of all I made the lid, with 10kg of the dense castable and 1.3 litres of water, mixed thoroughly.

I set the tin can in the centre of the mix and sunk the handles into it. Then I let it cure for 48 hours. The dense castable material is strange stuff, it's very dry and at first I didn't think it was going to cure. But 48 hours later it's hard as rock.


Making the body

I needed to make a hollow body for the furnace, so I used a small bucket filled with water in the centre to make the void.

I used 15kg of dense castable with 1.95 litres of water, which pretty much filled the bucket. I let this cure for 48 hours as well, and spent several hours cleaning all the gack off the kitchen table, floor and ceiling.

The mistake I made here was spilling some of the dense castable into the white bucket in the middle. When I poured the water out, there was a 2cm layer of rock hard material in the bottom - turns out it sets underwater just fine! I hacked it into little pieces and pulled it out with no problems.

Once it had set, I used a hole saw to cut a piece out of the side, and fitted a steel pipe to force air into the furnace. This is hooked up to Kat's hair dryer - shh, don't tell her!

Here's the finished furnace, the next step is to fire it up!

Here are some pics of the first time I lit it up, to melt some aluminium as a test. Aluminium melts at a much lower temperature than bronze, so it's easier to work with and cheaper.

The crucible is made of ceramic bonded clay graphite, it's a Salamander A2 from Castree Kilns. It's rated to 1600°C. The original instructions I followed used an old fire extinguisher, but I've been told that these are quite unreliable and prone to sudden failure.

Finally here's a quick video of the furnace in action:

The next step is to make a sword template out of wood and then cast it.

I've no idea how that works but it's going to be fun finding out!


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Making butter

Friday 24th April 2015

If you've never made butter at home, I'd really recommend it. The whole process takes ten minutes, and it's magical when the cream suddenly becomes butter. You can make it by hand if you like, but it's a lot quicker with a blender.

I made a short video of it, sorry about the dodgy camera work:

Here's what you'll need to make 275g butter:

  • A blender with a whisk attachment
  • 600ml double cream
  • 1 tsp salt
  • 1 litre ice-cold water

Put the cream into the blender and turn it on. After 3-4 minutes it will become whipped cream, and you might need to scrape it back into the bowl. A couple of minutes more blending and it suddenly changes texture into yellow butter with a watery buttermilk. Pour out the buttermilk into a container, it's great for making cornbread and pancakes, or you can just drink it.

Now you need to wash the rest of the buttermilk out of the butter to increase its life span. Add a cup of ice cold water and knead the butter with a spatula. The water will quickly go cloudy. Pour the water out and repeat twice or thrice until the water remains clear.

Add 1 tsp of salt and mix well into the butter. The less you handle the butter the better as it will melt, so I found a pair of butter pats in an antique shop which allow you to work it without warming it up.

You could also mix in some herbs, I used thyme and garlic which is perfect for spreading on toast for a snack.

Once you've got it into the right shape, refrigerate and enjoy!


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What's this about?

Hi I'm Mat and I'm addicted to new hobbies. I used to think this was a bad thing but now I'm embracing it.

Writing them all up in this blog encourages me to finish projects, and helps me keep track of which ones I've tried.

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