How to Make Mortar

Mortar is, quite literally, the building block of society.  It is the material used to bind construction materials together and fill the gaps between them.  From building a brick wall to a building, you’ll need to know how to make some form of mortar to make a reasonably sturdy structure.

It has been used since ancient times by civilized people to build buildings and walls and more.  If ancient people can make mortar, why can’t you?

Clay Mortar

In ancient times, the Babylonians used a mortar based of mud and clay.  Just get some clay mud that is wet enough to be a thick paste.  If it isn’t that malleable, add water.  If it’s too thin, add more clay or dirt to thicken it up.  This isn’t a very sturdy mortar and you can expect it not to last all that long, but it will do in a pinch and last long enough.  The key benefit of clay mortar is that clay and dirt are more abundant than any other resource for making mortar.

Gypsum Mortar

The Ancient Egyptians made mortar from gypsum and sand.  If you’ve ever worked with plaster of Paris (gypsum plaster), you’ll know that gypsum is makes a soft material, but when added with sand becomes a little more sturdy.  To make gypsum mortar, mix gypsum powder with water to make a slurry and add sand until it forms a thick paste.

Lime Mortar

Limestone is a clear rock mineral that can also be found in hardware/home improvement stores, but it can also be found in rock quarries as well.  To make the mortar, you will need to bake the limestone.  It will expand and turn white.  Even though you can make lime mortar without this step, it is very important to include it.  The reason being that untreated lime mortar is susceptible to water and can collapse.  Whereas, when treated in a kiln the lime becomes “hydraulic” and is much more resistant to the weather. 

After you let it cool off, add water to it.  The solid stones will collapse and hiss, this is normal.  Stir it to make an opaque slurry.  Add sand until it makes a thick paste.

Cement Mortar

This is the most abundant mortar in modern times.  You can find quick set cement in any hardware or home improvement store near you.  If you can’t find any (it’s likely someone else had this idea and looted it all after TEOTWAWKI.  If you’re lucky enough to have cement on hand, mix according to the instructions on the bag.

How to Build an Oven

In the P.A.W., it would be nice to be able to make a nice loaf of bread or even just cook something without using a campfire and risking burning your food all the time.  This isn’t as far-fetched of an idea as you may think.  In fact, you could build an oven to use while you’re travelling if you have the time.

The basic premise of cooking in a conventional oven is cooking by convection.  When you bake a loaf of bread in a modern conventional oven, the heating elements in the oven heat the air closest to the flames, causing it to rise, moving the colder air near the flames and repeating the process until the air inside the oven is a relatively uniform temperature.  You then place the bread dough in the heated air of the oven.  The heated air transfers its heat into the dough, causing the temperature of the dough to rise to roughly the same temperature as the air around it.  At this temperature, the ingredients in the dough cook and eventually you have bread.

Earth Oven

The easiest and quickest oven you can build is an earth oven.  You don’t need anything too special or permanent to build it – just some mud and a fire.  The basic concept of an earth oven is that you are creating an enclosed space that holds the heated air required to oven cook anything.

Because dirt/mud is exceptional at holding, we’ll use mud to build the shell of our oven.  We use mud because it is malleable until it drys, at which time it will hold its shape.  The first thing we need to do though, is find a way to make our oven space hollow.  The easiest way to do this is to use wet sand.  We can shape the wet sand into whatever form we want and the mud won’t destroy that shape, and dry sand is just as easy to remove from our oven as wet sand would be.  So we first make a mold for our hollow space, then we coat the mold with several inches of mud.  The thicker the mud walls, the more heat it will retain for longer.  Let the mud dry into a hardened mound, then cut an opening into one side of the mound all the way to the sand/molding material.  Dig out all of the sand/molding material and you now have an oven!  Build a fire inside the oven to heat the walls of the oven.  Once your oven is to temperature and the outside of the oven is hot to the touch, put out your fire and remove all of the fire material from the inside of the oven.  Place your food inside the oven and cover the hole up to avoid letting any heat escape.  Eventually, your food will be cooked.

Pompeii Oven

The Pompeii oven is a precursor to the modern brick oven, commonly used in pizzerias.  The Pompeii oven works on the same principles as an earth oven, and is actually the evolutionary successor to the earth oven, but it is more permanent and used with the fire still inside the oven while cooking.

For convenience, a Pompeii oven is built at around waist height or higher (because who really wants to crouch all the time while they are cooking?).  This is best acheived by building a dais out of brick or stone or some other material that is fire proof and resistant to age and the elements.

Then you want to build a slab that the oven will be built onto.  You might be fancy/lucky enough to have concrete and rebar to make this slab from, otherwise go for a material that is fire proof and resistant to age and the elements.

When considering bricks or brick material for building your oven, there are two factors to consider:

  1. Can the material withstand high temperatures? (refraction)
  2. How well can it reflect heat? (conductivity)

Ideally, you want a high refraction, low conductivity material because it won’t be destroyed by the heat of the oven and it will reflect heat given off by the fire efficiently.  Firebricks (bricks made of a type of clay composed of high levels of alumina and silica) are the ideal material, but ceramic and clay will work just as well.

Lay out a pattern of bricks on your slab for the floor of your oven.  Most people use an offset pattern for the floor because it prevents a seam in the floor which can cause your food to snag when putting it in or taking it out of your oven.  Ultimately, it doesn’t matter how you lay them out as long as they are tightly lined up with each other to prevent heat leakage.

To form the dome of the oven, you can either build it free standing, or over a wet sand mold as with the earth oven.  Building the dome free standing, you will lay the bricks one layer at a time and let the mortar dry before moving on, occassionally adding a wedge between rows of bricks to account for curvature.  Don’t forget to leave space for an opening!

If you don’t have access to modern mortar, you can use clay, mud, pitch (tar), or you can make your own.  Essentially, you just need something that will bind to your bricks to make a solid structure.

When building the door and door frame for the oven, you want to ensure that your door is at least slightly bigger than the opening in the oven.  This will ensure that the door doesn’t swing into the oven and, when closed, forms a seal to heat and moisture leakage from inside the oven.  Don’t make it an airtight seal.  An airtight seal will cause what is known as backdraft: The flame will go down as it burns through the existing oxygen, then when you open the door the onslaught of fresh oxygen causes the fire to roar back up, potentially exploding out the opening of the oven and burning you.  The door itself can be made from whatever you can manage: a hunk of scrap metal, dried mud, a rock, an old oven door, etc.

It is also a good idea to build a chimney into the door frame so that smoke and hot air have an escape path that isn’t your face.  _Don’t put a chimney into the oven itself!_  This fundamentally defeats the functionality of the oven.

After your oven is built, you need to purge it of any excess moisture.  This curing process ensures that your oven doesn’t crack when in regular use.  To do this, build a small fire for 6 hours each day for 5 days.  Start at 300F and increase by 50F each day.  If you can’t accurately guage temperature, just build a small fire and increase the size each day for 5 days.

Once you’re ready to actually start cooking with your oven, start you’re fire near the front of the oven and once it gets going, push it off to one side or the back and let the oven heat until the outside is hot to the touch.  Then cook to your hearts content!

Bear Grylls Leaves Discovery and ‘Man vs Wild’

via Reddit

In the realm of Survival TV, Bear Grylls reigns supreme with a full 6 seasons of his wildly popular show ‘Man vs Wild.’  That is, until this week.  Due to an ongoing “contractual dispute,” Discovery is cancelling all current production efforts for the show.  Not much is known at present as to what these disputes actually are. 

Regardless, “Man vs Wild” was one of those show I just loved to watch.  If you pay attention, you can learn a TON of survival techniques from it and it was also entertaining to watch.  I know that Bear didn’t always portray the show honestly (like staying in a hotel some nights), but it still made for good television.  I’ll miss “Man vs Wild,” but I look forward to seeing what new projects Bear Grylls works on in the future.

P.S. – Discovery, if you’re through with Bear Grylls, BRING BACK LES STROUD AND SURVIVORMAN!

Found on the Internet: Zombies, Run! An iOS game.

Most of what I write about here is skills, knowledge, and devices you will need for once Armageddon has occurred, but what about prior to that.  You need to do some prep work to be ready and preparing your body is probably the most important aspect.  The developer Six to Start brings you an iOS game that makes running/jogging/walking fun and puts you in that Zombie Apocalypse state of mind.  Basically, you are a survivor in a world overrun with zombies.  You have to avoid the zombies while collecting vital supplies to support your base.  After you’ve gone out collecting (aka running), you return to base with your supplies and distribute them among the survivors at base in order to help your base prosper.  The more thrivant your base, the more missions you have access to.

One of the things I really like about this game is that it allows you to play your own music while you’re out doing these things.  Also, according to their website, they plan on integrating their data with Runkeeper which is handy for all you Runkeeper users out there.

The app costs $8 from the iTunes store, which is a bit pricey for an iOS app, but what’s $8 when Armageddon strikes?

Zombies, Run! [via Lifehacker]