I needed learn how to make Green Sand for metal casting. If you watched the furnace video you saw me making refractory, and making green sand is about the same process. Simply put, it is a mixture of sand, bentonite clay, and a bit of water. Using this kind of sand is called green sand casting.
Since I had some fireclay left over I was going to use it, but after some research I realized that since fireclay vitrifies (fuses) with heat, I probably could not reuse it after I molded something. So I figured I would go with Bentonite (as everyone else does)
Where to Get Bentonite Clay Cheaply
If you cannot buy bentonite clay in bulk (luckily my ceramics supply store has it), you can grind up clumping kitty litter (cheap without additives) and reclaim the bentonite. It must be ground up VERY FINE and you will need a dust mask.
Bentonite now gets added to a 5-gallon bucket of “fine” masonry sand (I used play sand, but the finer the sand the better quality your castings will be). You need a 1 part clay to 9 parts sand. Mix this dry, and then add water in small increments (like coffee mug sized). Mix between additions over several hours. You want the clay to coat the sand evenly, so the more you mix and the slower you work the happier you will be.
Test if your Greensand is Packable
The next thing you need to do is check to make sure the sand is “packable” You can read about this in the Gingery book, or watch my video. Basically you just grab up a handful of sand and squish it in your fist. It should mold to your hand. Then break it in two. If the lump of sand holds its shape and breaks cleanly when you snap it then it’s good to go.
Store your greensand in a covered container (I use 5 Gallon buckets with lids) and the longer you store it (unless it dries out) the better it will be
More Resources:
You can read many good books and articles on green sand casting, or just the process of casing metal. I have several reviews on this site.
I like dehydrating food, sometimes because it makes food storage easier, and sometimes (like in the cases of apples or meat) I like eating dehydrated food.
The devils of food storage are:
Heat
Light
Oxygen
Moisture.
Dehydrating helps increase shelf life because many organisms (like Botulism) cannot thrive in dry spaces. If you vacuum seal moist food and botulism is present,the bacteria grow and create enough toxin to kill.
However, if you vacuum seal food with less than a 10% moisture level the bacteria stays dormant. So it does not produce toxins. This works well for things that you don’t want to super heat using a pressure cooker.
I have a pretty good electric dehydrator that I use to make jerky and other dried foods. However, it is small and takes up valuable kitchen space when it’s working. Besides that, my wife doesn’t sleep very well if I try to leave it running overnight. She worries about the catching the house on fire.
Research
Build it Solar was first resource I found online, and I went there quite a bit. The idea of the J R Whipple solar dehydrator is really cool, but I wanted it in wood. Root Simple also provided some ideas.
A large wooden shipping crate came from the trash and I decided to get to work.
*I later found a PDF entitled How to Build a Solar Crop Dryer that I believe this research was based on, I linked to it in my download section.
Building the Solar Dehydrator
Basically all I did was to cut a shipping crate to a manageable size, add a door, some legs and a few tray supports on the inside to make the drying cabinet. I will probably add some ventilation later once I know how much I need. I don’t want to cut a bunch of holes on the front end of the experiment as I don’t want to cut too many.
The next stage was to build the solar collector. My original idea was to use some glass scrounged from a storm door. Unfortunately, it was a couple inches too wide. (BTW you cannot cut storm door glass; it’s tempered and will shatter into thousands of pieces). But for an unnamed reason I ended up going with a large 24 x 60 piece of Plexiglass as the top of the collector. The sides and bottom end are 1×6 boards, and the underside is a piece of plywood I had left from my chicken coop shipping box project.
I cut the top end of the 1x6s at an angle (I did not measure the angle, just marked it as the angle it would take to lay flush against the drying cabinet with the bottom end of the collector sitting on the ground. This allows me to hinge the two pieces together so that the solar collector rests on the ground when in use, but folds up for storage. The inside of the collector is painted black to help absorb heat. I painted the outside white because I had white paint. I also cut some ventilation holes in the bottom end of the solar collector, as there will need to be airflow to remove the moisture out of the drying box.
The drying trays and screens for the air vents are aluminum screen. I simply made some frames out of strips of molding and stapled the screen tightly to the frames.
I still need to experiment with the correct drying times and amount of airflow needed, but the plan is to set this on the sunny side of my house, fill with vegetables and see how long it takes to turn them nice and dry.
Stay tuned, and I will add to this post as I learn more about my Solar Dehydrator….
From doing research into solar applications I have come to the personal conclusion that solar energy is misapplied in many instances. Our sun is an awesome source of energy, but all too often we use it to create electricity we store to make heat or light later. While this has some really useful applications, each conversion looses some of the original energy. If we focus some attention on directly using the solar energy we get more “bang for our buck.”
There is a really good book called Sunshine To Dollars that has some really cool projects that give you an immediate return on you investment of time and energy.
So after reading this book and others like it, I decided to make a DIY Solar Cooker. I resisted the urge to make a huge solar oven out of a new fiberglass tub my old tenants inexplicably left in my basement. What I decided to do was to build a small wooden solar box cooker. It would have been easier and faster to build one of the many cardboard cookers that places like Build it Solar shows, but I figured that since the technology was pretty well developed this was not an experiment, and I should probably invest the energy into making a more robust and permanent cooker that I could use rather than a throwaway model for a proof of concept.
I decided on building one modeled after a cooker I saw on youtube. The user supergokuel had a really cool 2 part video, so I basically just modified his idea.
I could not find any replacement glass sheets at the local hardware store, but I did find a sheet of Optix brand clear plastic that would fit very nicely on the box I was trying to make.
The bigger your cooker the more efficient it will be, and the larger the pots you can use, so my 1×2 sheet of plastic will work well. I also bought some screws, hinges, and a 4×8 sheet of exterior grade plywood. The black paint and caulking I already had.
Basically I just cut two side pieces in a rectangle, and then cut a 45° angle down one side. I made the rectangle wide enough so that the angled end would be as long as the shorter side of the plastic. (I know this is confusing, this video helps).
The ends and bottom of the oven are cut to match the side pieces and are screwed together to make a box. The top is simply the clear plastic sheet of Optic attached to the box by hinges.
I painted the box black to absorb heat, and when I get more reflective film I plan on mirroring the inside of the box to help generate more heat. Larger box type collectors can get hot enough to bake or roast meat – upwards of 220°
This is a pretty simple project using hand tools and a power saw, but will allow you to cook many types of foods without electricity. For us disaster conscious types, the ability to bake and cook foods outdoors on something other than a grill or campfire has some serious advantages. For those that choose to reduce the use of resources – whether for ecological or self-reliant reasons, this is also a very useful project.
This is a project that I would highly recommend you duplicate of modify for your own usage.
The way I approach prepping is that I have a list of tiers of preparedness, and I try follow a consistent approach of not jumping tiers for specific sections until all sections on a tier are filled (This is flexible based upon situational factors).
In my Defense tier, I would really like to have .45 Camp Carbine with an integral suppressor and mounted thermal imaging. If I spent my resources on that and only had a CB radio and a 72 hour kit as my only other preps, then I would not be spending my resources wisely.
It is most cost effective to buy a year supply of food using the LDS list before you spend twice as much on a 3 month supply of freeze dried food.
Water Purification is Important
That being said, you might have noticed I am on a water purification kick. Some of that is that I have noticed the amount of water I have been using on livestock and gardening. Some is that I realize its impossible to store water for an extended period due to space and weight issues. The third reason is that I ended a preparedness tier with my Calcium hypochlorite prep. One small purchase game me the ability to disinfect approx 50k gallons of water. It is easiest to start the next tier on water since that’s what I have been researching lately.
What is a Chlorine Generator
Today’s project is a device used to create a practically inexhaustible supply water purification chemicals. Basically, it make the same disinfecting solution as the calcium hypochlorite makes. You might ask why I went through the trouble of buying the HTH pool shock if I had planned all along to make a device that does the same thing. Especially considering the storage considerations of the corrosive chemical. Well, the pool shock is does not need an energy input to work. I cannot break it. Additionally, I bought a lifetime supply for under $25.00.
The DIY Chlorine Generator for Water Purification is also called a Chlorine Producing Unit (CPU) I am about to show you works very well, but it requires 12 volt electric input, uses expensive and technologically advanced electrodes and cost a little over twice as much to make.
I have found that American missionaries that work in the third world are an excellent supply of information in what some call “appropriate technology” This is people centered, small scale, labor intensive, energy efficient, environmentally sound devices and processed. It’s a lot like “Macgyverisms” from my favorite 80’s TV show. He had advanced knowledge and primitive supplies and was able to cobble together 1900’s level tech with modern scientific principles.
One famous example of this is the CD3WD which is a collection of appropriate tech, Travis Hughley and barrelponics (which I AM going to build one day) and Safe Water International Ministries the developers of the CPU that is the focus of today’s article.
SWIM has developed the CPU to provide a chlorinating solution for water disinfection in third world countries. I would highly recommend you check out their website and consider donating to their mission as they are doing wonderful work.
Comes in a Complete Kit Also
If you want a CPU, but don’t have a DIY gene or interest in building one yourself, SWIM sells complete CPU tool box kit which includes an instruction card, a chlorine test kit, 2 mixing bottles, a salt measuring cup, and a couple of solution droppers. All you need to provide is 12 volts of electricity, salt, and water. A donation of $150 to their ministry would support this kit.
I wanted to turn this into a project so I gave a $50 donation and received the anode and cathode from them. They will email you the plans for free if you contact them on the website, and they have a technology link online with the instruction manual and a basic lesson plan for teaching this to others. I will warn you, the cathode and anodes are the main expense in the CPU, and you may have a hard time finding a supplier. One is a titanium mesh; the other is a mixed metal oxide (ruthenium).
However, I must tell you that their primary mission is to provide these units for missionary work in third world countries, so if demand causes a supply backlog, I would imagine they would fill that need first.
Basically what happens is when you bridge the electrodes with a salt water solution and apply an electrical charge to them you start a chemical reaction called electrolysis. In this particular process the water bubbles and produces a caustic chlorine solution roughly half as strong as laundry bleach. After the 9/11 attacks many municipal water treatment plants converted to this process so that they could remove their one ton chlorine gas tanks from their sites to mitigate their attractiveness as a terrorist target.
Per the SWIM for Him website the directions for use are:
Mix salt & water solution ( approx. ¼ cup salt to 16 oz water)
Connect wires to 12 volt source (negative, or black, to negative; positive, or red, to positive)
Pour the saltwater solution through the CPU into another bottle (observe the bubbling process)
Carefully repeat the pour-through process 5 times.
This is different from a chlorate cell as that the water free flows through the unit which does not allow chlorates or perchlorates to form. This process operates at a different voltage and a much lower temperature.
Unhook the battery wires.
Rinse the CPU by pouring clean water through it.
Add 10 drops of the solution for each gallon of drinking water.
Wait one hour before drinking.
It works with Solar Also
Additionally, if you are using solar power to charge your battery, you will want to recharge it for 3-5 hours after this process to ensure it is fully charged.
You will also need a test kit to ensure you use enough chlorine solution to properly sanitize your water supply.
This was a very simple project and I built the device in under an hour, I have to wait about 24 hours for the sealant to set, and then another 30 minutes in finishing touches. Please watch the video below to see all the steps.
I like dehydrating food, sometimes because it makes food storage easier, and sometimes (like in the cases of apples or meat) I like eating dehydrated food.
From doing research into solar applications I have come to the personal conclusion that solar energy is misapplied in many instances. Our sun is an awesome source of energy, but all too often we use it to create electricity we store to make heat or light later. While this has some really useful applications, each conversion looses some of the original energy. If we focus some attention on directly using the solar energy we get more “bang for our buck.”
The way I approach prepping is that I have a list of tiers of preparedness, and I try follow a consistent approach of not jumping tiers for specific sections until all sections on a tier are filled (This is flexible based upon situational factors).