Found on the Internet: The GoSun Stove

The GoSun Stove

I found this little gem on Kickstarter today.  The GoSun stove is solar-powered stove that can reach temperatures up to 700F and can cook a meal in 20 minutes in moderate sunlight.  If you read this site regularly, you know that I’m a big fan of devices that don’t have depleting resources (fuel, batteries, etc) and this little bugger fits the bill.  Not only that, but it’s lightweight, coming in at a a scant 4 lbs.  I feel like this should be something to put in a go bag.

GoSun Stove: Portable, High Efficiency Solar Cooker [via Kickstarter]

Found on the Internet: Post-Apocalyptic Key Replacements


I’ve never really thought about locks and keys in a post-apocalyptic world.  But what happens if you have a lock and you need to make a spare key?  Steel will be hard to come by and there are much better uses for it than keys, modern key duplicators require electricity, if you were to make one by hand you need some skill and could potentially waste a key by misshaping one of the projections.  Hackaday presented a post on how to (fairly) easily duplicate a key in the post-apocalyptic world.  You basically use a plaster mold of the key and zinc for the key.  Simple, elegant, my kind of process…


Making keys after the apocalypse [via Hackaday]

Found on the Internet: How to Weld


Despite my penchant for post-apocalyptic knowledge, I’m still a huge geek at heart.  I watch a lot of youtube videos and spend a lot of time on the internet.  I’ve watched Geek Beat TV since it was Geek Brief and recently they’ve been branching out to things not so tech related.  For instance, the above video shows (in much better detail than I could show you) how to weld.  I’ve written before on welding, and I feel like it’s a skill that could be helpful today as well as in an apocalyptic scenario.

Found on the Internet: Map of the Dead

World view of the likely danger zones in a zombie apocalypse.

If you haven’t been under a rock for the last 5 years, you’ve been privy to (or involved in) the zombie apocalypse craze.    People are fascinated with what would happen in a zombie apocalypse.  How would it spread?  How would you survive? The website Map of the Dead gives you some answers.  On a macro level it shows you danger areas – places that will have a higher level of outbreak mixed with higher population density.  On a micro level, it shows you important places to you if you are trying to “survive” – clothing stores, medical facilities, sporting goods store, etc.

While this is ultimately a whimsical look at a fantasy future, it does show a few things that should interest you Armageddon survivors out there:

  1. The red zones it shows on the macro level show outbreak danger zones, regardless of what the outbreak is.  Be it zombies, superflu, the black plague, SARS, swine flu, or any number of other disease.  If a pandemic starts, it’s more likely to spread to these places and more quickly.
  2. The locations of interest the map displays at a micro level are actually places that you should be aware of.  These places are the places that you need to scavenge at to get needed supplies.  Unfortunately, many other people know about these places too, so they could already be cleaned out or you may have to fight over resources.  This is why I always stress preparedness.


How to Make Soap

If you haven’t noticed in my writing, I’m very much against being wasteful.  At home, I hate making food from a recipe where you only use a part of something and throw the rest out.  When I explained how to make biodiesel I briefly noted that you could use the leftover glycerin to make all sorts of things.  One of those things is soap.  Don’t get me wrong, soap is absolutely a luxury item.  But ideally, for every liter of biodiesel you make, you’ll end up with 200mL of glycerin.  That adds up, so why not make some soap.  You’ll be clean and you can use it to barter with other people.

Bar Soap or Liquid Soap?

Interestingly enough, the procedure for making bar or liquid soap is essentially identical.  The only difference is what type of lye you use.  Something about sodium hydroxide causes the glycerin to crystallize during the saponification process that doesn’t happen with potassium hydroxide (chemists or chemical engineers, feel free to let me know the specifics).  So if you want bar soap use NaOH, otherwise use KOH.

It should also be noted that if you used a different type of lye in the biodiesel process than you are using to make soap, your soap may not turn out exactly how you planned.  If you are making bar soap, you can add more NaOH to help it solidify, but if you do, you need to let it sit for longer afterwards to ensure all the lye has reacted.


  1. Glycerin, and lots of it.  This is the ingredient that all others are keyed off of, so it doesn’t matter how much you use.
  2. Water. You need 200mL of water for every liter of glycerin.
  3. Lye.  If you are using sodium hydroxide (NaOH) you will need 50g per liter of glycerin.  If you are using potassium hydroxide (KOH) you will need 75g per liter of glycerin.
  4. Smelly Stuff.  You don’t really need this, but if you want your soap to smell pretty you’ll need something to make it do so.

The Procedure

  1. First things first, you need to clean your glycerin.  This ensures that you have no particulate matter (dirt, old food, twigs, leaves, zombies, etc.) in your glycerin.  You typically don’t want these things in your final product, so get them out now before your process becomes more complicated.
  2. Remove any alcohol remnants.  Any alcohol left in your soap can be bad for your health, especially methyl alcohol.  You need to bring your glycerin to a temperature of 65C for methyl alcohol or 80C for ethyl alcohol.  FOR THE LOVE OF PETE, be careful when you do this.  What you are doing is boiling of the alcohol and methyl alcohol will sink.  So make sure that you do this in a well ventilated area do everything you can to avoid exposing your flame to the vaporized alcohol.  If your flame turns an odd color or starts to crackle, then disperse your flame and rethink your setup.
  3. Once you are sufficiently sure that there is no alcohol left in your glycerin, begin heating it to 60C.  While you wait you can combine your water and lye.
  4. Add your water and lye to the glycerin.  Stir continuously and heat to boil.
  5. Once at a boil, reduce heat and let simmer.
  6. If you’re making smelly soap, add your smelly stuff at this point.
  7. Once a skin starts to form on the surface of your concoction, check it by ladling out a spoonful and pour back in, if a film is left behind, it is done.
  8. If you are making bar soap, pour into molds.  If you are making liquid soap, pour into the containers you intend to store it in.
  9. Let the soap sit for around 3 weeks.  During this time, the glycerin and lye are reacting and you need to let this reaction complete.  If you try to use the soap and it burns or tingles, it isn’t ready yet and you just gave yourself a lye burn.

As you can see, making soap is really easy and a good use for the glycerin byproduct of biodiesel.

How to Make Biodiesel

Traditional diesel fuel is made from petroleum, and in a post-apocalyptic world that will be hard to come by.  Thankfully, biodiesel is an alternative that can be made from any organic oil or fat that doesn’t require any kind of modification to your diesel engine.

Generally, you are adding a catalyst to a triglyceride-rich liquid in order to break a glycerin molecule off of the fatty acid chains in the oil and forcing each of three fatty acid chains to recombine with the introduced alcohol to essentially create a new alcohol.  This process is called transesterification.

Transesterification: ester + alcohol = different ester + different alcohol
Transesterification: ester + alcohol = different ester + different alcohol


Organic Oil/Fat

This can be nearly any kind of oil or fat (I’ve seen biodiesel made with rendered pig fat).  There are a few considerations to take into account though:

  • Peanut oil, coconut oil, palm oil, tallow, and lard all have a higher clouding point than other oils, meaning that they start to crystallize and gel at a higher temperature.  This means that they will work perfectly fine in warmer weather, but may cause problems in cooler temperatures.
  • Olive oil, peanut oil, palm oil, tallow, and lard have a higher acidity.  This can interfere with the transesterification process and means you probably want to titrate a sample (explained later) to determine if extra lye will be needed.
  • If you are using used oil, you need to process it before going forward with the recipe.

Rapeseed (or canola) oil, corn oil, soy oil, and sunflower oil are considered to be the preferable choice for biodiesel production.


It is possible to use either methyl alcohol or ethyl alcohol for biodiesel.  Methyl alcohol is preferable because there is less work involved with methyl alcohol.  Either way, you want as close to 100% pure as possible.


There are two types of lye potassium hydroxide (KOH) and sodium hydroxide (NaOH).  Either can be used, but KOH is preferable since it dissolves easier in alcohol.  Also, conveniently enough, it can be made per the instructions I give in How to Make Lye.


  • 10 parts oil
  • 2 parts methyl alcohol or 2.7 parts ethyl alcohol
  • 3.5 grams NaOH or 4.9 grams KOH per liter of oil used (plus any excess lye as indicated in titration for used oil)

The Process

Biodiesel and Glycerine separated into layers
Biodiesel and Glycerin separated into layers

Mix your alcohol and lye in an HDPE container (like a milk jug) and swirl occasionally until all the lye is fully dissolved.  This could take as little as 10 minutes for KOH and as much as overnight for NaOH.  This creates you methyl or ethyl esters.

Blend the ester mixture with oil/fat heated to 55C for roughly 30 minutes.

Let the mixture settle for 24 hours.  In this time, transesterification will occur, leaving behind glycerin as a by-product.  Three distinct layers will form, the heavy (bottom) layer is the glycerin, the light (top) layer is the biodiesel, and the middle layer is a soapy emulsion created by the reaction of lye with oil.  You can keep the glycerin, as it is useful in other situations, but unneeded for the rest of this recipe.  Move the biodiesel into a different container, ensuring that no glycerin or soap is carried along, and either store the glycerin or through it out.

Quality Testing

  • The Wash Test – Put a small amount of fuel in a PET bottle with water and shake vigorously for  approximately 10 seconds.  Let it sit for a half an hour.  If water separates from fuel with a very thin, foamy layer between (or no layer at all), then you’ve produced quality fuel.  If they don’t separate or there is a thick foamy layer, then your fuel is of poor quality.  This can be caused by too much lye or contaminants present acting as emulsifier.
  • The Methanol Test – Mix 25ml of biodiesel with 225ml of methanol.  If anything is going to separate, it will happen nearly instantly.  Each milliliter of biodiesel that separates from the methanol equals a 4% impurity.  Ideally, nothing will separate, meaning your fuel is 100% pure, but a little bit won’t hurt.


After testing to ensure your fuel is good you need to “wash” it.  This process removes any physical impurities or unconverted ingredients from the fuel, as these can all cause problems in your engine down the line (lye can corrode the fuel injectors and fuel tank, glycerin and soap can clog any number of parts, etc).  Mix 1 part fresh, clean water with 2 parts biodiesel until it appears homogenous.  Let the mixture settle for several hours, then drain water.  Move fuel to new receptacle and repeat process 2-3 times.  Let the fuel sit for several days. once it is no longer cloudy, it is “dry” and ready to use.  If it doesn’t clear up, you can try washing it again.

Processing Used Oil

You can use “certified pre-owned” oil to make biodiesel, you just need to do some things to it first.

Cleaning Old Oil

Some people recommend filtering the used oil first, but I say that it is unnecessary.  All the gunk and goo in the old oil will sink to the bottom and since you are usually working with the top layer of a separated liquid, you are naturally filtering it as you work with it.  However, there is a significant amount of water suspended in used oil (typically from the food cooked in it) and that can be a problem.

To remove the water, bring the oil to a boil at 100C and leave there until boiling slows, then boil at 130C for approximately 10 minutes.  This should ensure that most of the water is removed.


Every time you use or heat oil you create free fatty acids, which are basically broken-down triglycerides.  This means that there is more work required to convert your oil into biodiesel than with new oil.  This work is done by adding extra lye to the process.  To find out how much more lye to add, we use a process called titration.  This process should also be used if you are using ethyl alcohol instead of methyl alcohol, or an oil with a higher acidity.

First, make a 0.1% lye solution by mixing 1g of lye into 1 liter of distilled water.  Now dissolve 1ml of oil in 10ml of isopropyl alcohol.  At this point you need to choose a way to determine the pH of the oil/alcohol mixture.  You can use a pH tester, phenolphthalein droplets, or (if push comes to shove) red cabbage juice – seriously it indicates pH really well..  Add the lye solution drop by drop until pH is around 8-9.  If you’re using phenolphthalein, this is indicated by the liquid turning a pinkish color, if you are using red cabbage juice you are looking for a blue/blue-green color.  The number of milliliters of lye solution added to the oil solution equals the additional number of grams of lye per liter of oil to use in the transesterification process.


If you want to get super technical in your measurements, the amount of KOH used depends on the strength.

Purity Measurement (in grams)
99% 4.9
92% 5.3
90% 5.5
85% 5.8

Red Cabbage Juice

pH 2 4 6 8 10 12
Color Red Purple Violet Blue Blue-Green Greenish Yellow


How to Distill Alcohol, part 3: How to Make Methanol

[error]DISCLAIMER: The following is highly dangerous or illegal and it is not recommended to be used under any circumstances, except zombies.[/error]

Methanol, or methyl alcohol, can be used primarily as a fuel source or feedstock (a chemical used to make another chemical).  For our purposes, we can either use it to fuel cars, trucks generators, etc. or to create biodiesel (both very useful in a post-Apocalyptic world).  In this part of our series on alcohol distillation, we discuss how to use your still to produce methanol.

Methanol is more commonly referred to as wood alcohol because, until breakthroughs in modern chemistry, the only way to produce it was by extracting it from wood.  You shouldn’t drink methanol EVER.  Not only does it taste bad, but it can kill you.  In fact, methanol is used to denature ethanol products, rendering them undrinkable by making you violently ill when you drink even that small of an amount.  If you want to make drinkable alcohol read about it here.

Producing methanol is a much less involved process than producing ethanol.  Put wood chunks or shavings (or paper) into the bottom of your cooking vessel and add enough water to cover the wood.  Heat the cooking vessel to around 78C and wait as the methanol vaporizes from the wood and out the condenser coil and into your storage container.

If you are making both ethanol and methanol make sure you label them.  I can’t stress to you how important it is that you don’t drink methanol.