First make the black powder mix. Use Potassium Nitrate, Air Float Charcoal,80 Mesh Charcoal, Sulfur in the ratio of 16:6:3:4. This is a optimum mix ratio, grind all the mix into a container and make a fine free flowing powder. Pass it though a mesh preferably 20 Mesh steel mesh.
Take a 4 Oz Engine tube for making the Body of the rocket. Now ram the fine grained black powder mix into the tube up to 80% and a little air room. You can use a ‘ram through funnel’, which will make our task easy, the rammed materials inside the body of the rocket should be hard.
Now fill in clay after making it a little moist and fill it in the space where the room for air has been left. Now punch a thin hole in the clay using a thin object, say needle. This is for the fuse. A ready made fuse can be obtained from a firecracker or by coating a cotton string with the same black powder material.
Attach the fuse to the under part of the rocket body through the clay, also make a conical head of paper materials.
Now tape a long stick to the rocket for stability. The rocket is ready now, bury the stick in the sand upright and light the fuse, watch it skyrocket upwards.
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