Primitive skills are simple, but they are not easy to learn. For making a bow drill, you have to assemble everything for it, from nature. To make fire with a bow drill, it is important to get your materials properly assembled. The best thing, to begin with, is the baseboard or a fireboard.
The base board should be wider. The board will last for a long time, and if you choose a hardwood, you will be glad to get a lot of fires from it. Most suitable measurements for the board will be 2 inches x 8 inches and ½ inch thick. The second most important thing in making of bow drill is a drill.
The drill dimensions can vary. The smaller the diameter of the drill, the faster it will spin. But if it is too thin or too long it may snap under the sideways pressure from the bow. A thin drill may also drill quickly into the board. A good width to start out is a ¾ inch. The drill will wear down quickly at both ends so don’t start with a too short drill. Once the drill gets shorter than 3 inches, holding it steady with rock gets more difficult. The top of drill should be sharply pointed, so it can spin freely in the rock without slipping out. The bottom of the drill should be fairly flat. This provides maximum friction between the drill and the base, ensuring plenty of dust and heat.
The bow that spins the drill should be about 1 foot and 8 inches long with a natural bend. Makes sure it is long enough, so you can take full strokes, which allow your arm to be fully extended in front of you. It is good to have a bow that is dry.
A fork on the end of the bow where you hold it is ideal. A string can be wound around the fork to secure it, instead of trying it down under your hand. The string stretches as it gets hot and fork allows you to adjust the tightness of string easily without making an adjustment on each stroke.
The tension of bow string should be tight but not so that you break the bow or string while putting it around the drill. Still, the cord needs to be tight enough so that you feel tension when twisting the drill into the string.
A rock or something else is also needed to hold the drill steady and apply downward pressure to the drill. The rock should fit comfortably in your hand. Almost any stone, you can make a hole in, works well. A piece of hardwood can work instead of rock, but the top of the drill can smoke and bind in the hole. Whatever you use, make sure the hole is deep enough.
After assembling all the pieces of bow drill set, put a leaf or a wood chip under the notch to hold the coal and start drilling, keeping notch and drill steady. Apply good downward pressure using your upper body weight to press down on rock but keep it steady. Stop when dust pile is smoking on its own. Keep practicing; you can do it. The magic of creating fire is in your grasp.