We continually update this list of Frequently Askes Questions (FAQs). Check back often.
Q: Can the NichroPulse team help design a custom product for me?
A: Yes. We can provide analog, firmware, mechanical and graphic overlay design services. We can take your idea from concept to high volume manufacturing and outsourcing. We are very thorough in documentation and test procedures, and have great communication skills. The cost and or licensing is negotiated on a case by case basis. Please contact our
department for these types of inquiries.
Q: What does the sugar do in sugar/nitrate rocket motors?
A: Sugar is the fuel in this chemical combustion reaction. Potassium nitrate provides the necessary oxygen for the combustion reaction to take place. In order to burn, fuels need oxygen for combustion. For example: a campfire uses wood for fuel, and oxygen from the air. One way to speed the reaction up is to homogeneously mix the oxygen in with the fuel. So, if you were to take some saw dust or powdered sugar and throw it into the air and ignite it, it would create a fireball! When we need an even faster combustion in a small confined space like a rocket motor, we use what is called a solid oxidizer, like potassium nitrate. The oxidizer breaks down and releases its oxygen atoms when heat is applied. This oxygen is now free for rapid combustion with the fuel. As you might expect, a smaller particle size will allow a more homogenous mixture, which will give an accelerated and often more complete combustion. Taking that a step further, oxygen can be mixed with fuels into a single molecule which makes up a compound.
Q: What is the core hole though the center of the rocket motor propellant grain for?
A: The core allows the flame to shoot up the center at the beginning, and perform a cylindrical burn, which increases the speed of the burn by increasing the surface area of the burn.
Q: My rammed-propellant 3/4" sugar rockets keep exploding, what am I doing wrong?
A: The perfect-nozzle 3/4" motors usually explode due to too much surface area of the grain burning, causing a much-to-rapid burn-rate, thus increasing pressure beyond the motors bursting pressure limit. The following is a good check list to go though:
- Core surface area is too large (if fixed diameter, then core is too long).
- Too much oxidizer (ratio should be 65/35 KNO3/Sugar BY MASS not volume). Mix it VERY well; it must be homogeneous to avoid "hot spots" which cause "chuffing" or explosion.
- Propellant not packed hard or uniformly enough. Symptoms may include "chuffing" or explosion, but most often explosion. (Pack very well in small (1/2 TBSP) increments to get dense and uniform enough grains without resorting to the proven casting method. Cast grains can also crack. When the flame front reaches a grain boundary crack, the surface area is suddenly increased, and can cause an over-pressure situation.
- Nozzle and/or end-plug not adhering to the tube well enough.
- Nozzle throat diameter is too small. If the throat diameter is too small, the pressure will build up too high, which in turn causes the propellant burn-rate to increase. As you might guess, this is a catastrophic runaway situation.
- Tube-flex. This is where the pressure inside the tube flexes the tube giving space around the propellant grain which the flame front can engulf the entire grain giving it a very large surface area. In the 3/4" PVC motors, this happens when the propellant grain and tube is too long. Larger motors using cast propellant use sleeves around the grains to mitigate this problem. The sleeve blocks the flame from igniting the outside of the grain while allowing the outer pressure bearing tube to flex.
Q: Why does my AngrySpark III reset at the end of a countdown?
A: This can be caused by operating with very cold AA batteries not designed for low temperatures below freezing. Make sure you use fresh batteries when operating in cold conditions, and warm them if possible. For cold temperatures, we always use Lithium 1.5V AA cells. For instance, the Energizer Ultimate Lithium batteries work much better than standard alkaline below freezing.
Q: Why won't the Angry Spark III work with Estes or Areotech ingiters?
A: The Angry Spark III is for medium to low energy igniters as listed. Estes and Aerotech igniters require higher energy than the Angry Spark III output capacitor produces. Ignition energy of an igniter has two components; a current (or power) and an amount of time the current (or power) is applied. The Angry Spark III can apply very high currents as its output capacitor begins discharge, but the length of time is limited due to the capacitor's charge limit. The voltage across a discharging capacitor decays exponentially with time. That is why a good 12 battery can ignite an Estes igniter; the current (and power) is DC.
The Angry Spark III works very well with the common Quest Q2G2 igniter as well as with many other electric matches. If you would like to use the Estes and Aerotech igniters, we do not recommend that you buy this product. This system is designed for professionals, who can obtain professional E-matches.
Q: Is the Angry Spark III difficult to operate?
A: No. Most people find it very easy to operate right out of the box with default settings. Granted, it is not as simple as a push-button controller, however the additional features that it provides do not allow it to be quite that simple. This product is for ages 18+.
Q: Can the Angry Spark III be re-programmed to allow other possible features?
A: Yes. For a fee you can have the Angry Spark III programmed to meet your needs if it is possible. If you are ordering 10 or more at a wholesale price, the fee is often waived.
for these inquiries.
Q: How do I tell if my Angry Spark III has good batteries?
A: Disconnect the output terminals from any load. Set the timer to zero. Arm the system by holding the "Arm" button down for 5 seconds. When the display reads "charge", release the arm button. The system allows 10 seconds to for charging, and will display "Lo-batt" if the batteries are not strong enough to perform a proper charge. You will not be able to perform a instant manual fire. Press the arm button to clear the error, or cycle the key-switch interlock.
Q: What type of output does the Angry Spark III have to ignite electronic matches ?
A: This electric match timer system utilizes a capacitive discharge output. That means, just before firing, an internal capacitor is charged to 100V. Upon firing, the capacitor is connected to the output terminals, supplying a pulse of energy to the electric match. The duration of the pulse will be determined by the resistance of the E-match. Higher resistances will give a longer pulse times, but the total amount of energy will remain the same. The resistance of most electric matches is bewteen 0.5 and 3 ohms. We reccommend e-matches with a resistance of at least 1 ohm for the Angry Spark III system. E-matches with higher resistances use a smaller size nichrome bridge wire, and the Angry Spark is designed for 38AWG wire or smaller. (Video demostration of our E-match timer pulsing energy through a 40AWG nichrome wire)