Pyrotechnic Projects: Real Visco Rockets
Is it Rocketry or is it Pyrotechnics?
Initially developed as strictly a fire producing device, the intention was to use these devices in conjunction with KNSU rockets to produce a visible flame for aesthetic effect. It was then discovered that these devices produce enough thrust to fly “Micro Rockets” !
The housing is 2" long, and was fabricated from .375 (3/8") hydraulic line with a .020 wall thickness. It is an open end burner. One end is plugged with .25" Bentonite Clay. There is no nozzle restriction at this time. . . I reserve this for future experiments.
The propellant is 5, 1.5" lengths of 3mm Visco fuse. It has a 1.5" length of 2.5mm Fast Burning Yellow Vis-Quick fuse in the core. The Fast Burning Yellow Vis-Quick fuse seems to be the trick. This fast burning fuse burns at 3 sec per foot, so a 1.5" length will burn in less than 1/2 second. This ignites the 5 pieces of 3mm fuse from the core.
The result - a quiet whoosh (about .5 seconds) with a 3 ft flame and a small amount thrust. Enough to propell a 4 gram rocket (pictured above ) 50-75 feet !
WARNING - Though minimal thrust is produced, this device produces a 2-3 foot flame. This creates a burn hazard if improperly used. Launch pads will be scorched from this device. Build and use at your own risk.
Note : This procedure uses a 2" length of aluminum tube. The 2.5 mm Visco is cut longer for illustration purposes. This fast burning fuse may be cut to the same length as the 3 mm Visco.
Note: Do not “bore” a hole - This action should pack the 3 mm fuse sections against the housing wall while maintaining the pentagonal pattern. This should also open and expose a hollow core in the middle of the fuse sections. 8. Shove the 2.5 mm Fast Burning Visco all of the way into the hollow core. 9. A piece of visco fuse can now be added for ignition. (1.8 mm fuse works good).
WARNING: This device produces a 2-3 foot flame. Do not attempt to light this device without a delay fuse or electrical ignition. Do not attempt to light his device at the fast burning fuse. Burn injury will occur !