If you’re unsure whether or not the rock that you’ve collected is limestone, use a coin to scratch the surface of the rock. Limestone is soft and can be scored by the edge of a coin.
Aim to break the limestone into pieces not larger than 2 inches (5. 1 cm) across.
Always wear thick work gloves when working with a kiln. The gloves will also be useful when you’re pulling the baked lime back out of the kiln, since it could severely burn your skin.
The baked limestone is called quicklime. Consider wearing some kind of respirator when pulling the quicklime out of the kiln. Quicklime is harmful to the body, and even breathing in its dust can harm your lungs. [7] X Research source
If you need to store some of the crumbled quicklime for later use, store it in an airtight container.
If you are using the cement for a variety of projects or are not familiar with using cement, purchase either a regular (multi-purpose) or fast-setting mix (like Quikrete). Consult the sales staff at the hardware store for additional help selecting a type of cement or concrete.
If you prefer not to buy cement with aggregate already included, you can also purchase gravel at a hardware store and add this into the aggregate-free cement later.
To protect your eyes, you should also always wear a pair of safety goggles when working with cement. Since cement will harm your lungs, think about wearing a surgeon’s mask or bandana over your mouth when pouring dry cement.
If you prefer to use a machine mixer rather than mixing by hand, you’ll pour the opened bag of cement into the machine basin. [12] X Research source Avoid shaking the bag as your pour out the cement powder. It’s very dusty, and shaking the bag will fill the air with cement powder.
If you’re mixing multiple bags of cement, you’ll quickly get the hang of how much water is necessary.
Stir slowly, so that the water doesn’t slosh over the sides of the wheelbarrow. If you’re using the mixing machine, simply flip the “On” switch and let the machine stir for you.
The technically correct ratio of mixing cement with sand is 1 part cement, 3 parts sand, and 3 parts water. [15] X Research source However, you can customize this ratio as you see fit. For most projects, you won’t need 3 times as much sand as cement. Start with a 1:1 ratio instead. If you’re planning to add aggregate to your concrete mixture, add the aggregate now as well. Add sand and aggregate separately to ensure that each gets fully mixed into the wet concrete.
A clay-rich mud or soil will result in a strong, durable cement.
Green grass will not work. The grass needs to be dry and hard in order to make suitable survival cement.
For most projects, the grass will work best when cut into sections between 6 inches (15 cm) and 12 inches (30 cm). [19] X Research source
If you don’t want to get your shoes or feet dirty, fold a corner of the tarp on top of the mud and grass and stomp on top of that.
At this point, your survival cement is finished. Begin shaping and working with it immediately, as the mud will dry quickly. You can form your batch of survival cement into a series of bricks, which can be built into a small hut in adverse survival conditions. In non-survival situations, you could use these cement bricks to build a retaining wall or fire pit.
