Building and Launching Your First Model Rocket
by Maker Mechanic in Outside > Rockets
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Building and Launching Your First Model Rocket
I was first introduced to the hobby of rocketry 20 years ago while in high school, and now as an adult, I have regained interest in the hobby. This instructable will follow along with the assembly of a model rocket kit, and it's first (hopefully successful) launch.
Supplies
Model Rocket kit - I chose a starter set that includes the launch pad, launch controller, and a model rocket. There are of course alternatives to this method, but doing it this way will get you off the ground faster.
Rocket Engines - you won't make it far without these, I chose a low power engine for the first launch
Recovery Wadding - this protects your recovery system from the pyrotechnic that separates the nose cone for recovery
A copy of the NAR model rocket safety code - you are building a cardboard and plastic missile, Following the safety code will make sure no one gets injured.
Other things you'll need are a ruler, pencil, some glue (the kit calls for carpenter's glue), and a hobby knife. You'll also need batteries for the launch controller.
Being Safe.
Before assembling your kit, it's best to familiarize yourself with both the NAR safety code, and the Estes rocket website. The Estes website provides information about the anatomy of a rocket flight and how a rocket motor works. I've linked some pertinent info below:
NAR.org Introduction to the hobby
I know it doesn't seem to be much of a first step, but understanding how a rocket works and the anatomy of a launch will help you have a successful launch with a successful recovery. This means you get to launch over and over again!
Assembling Your Rocket and Launch System.
When you open your kit you'll find multiple pieces inside. The rocket kit, the launchpad, the blast shield for the launchpad, launch controller, and launch rod all are inside.
First lets assemble the launch pad. Inside the bag are three legs, a center piece, a metal blast shield, and a small cone shaped piece.
The three legs slide into the slots on the center piece of the launch pad. The center piece has a metal wing nut on one side of the top.
Next, take the small cone and insert it into the blast shield and turn it 90 degrees to lock it in. It may seem loose still but that's ok.
Then assemble the three pieces of the launch rod, you'll notice two pieces have a smaller diameter on one end than the other. These are inserted into the hollow ends of the other rod pieces until you have one long launch rod.
The launch rod is inserted into the center piece using the smaller of the two holes on top, the larger hole is for use with a larger diameter rod used to launch larger rockets. You may have to loosen the wing nut before inserting the launch rod, just be sure to tighten it up by hand to secure the launch rod.
Then the assembled blast shield can be slid over the launch rod.
Now that your Launch pad is assembled we can move onto the Alpha III rocket included in the kit.
Note: the launch pad is designed to be easy to assemble on site.
Now we can finally become rocket scientists! Well at least a rocket builder....
The instructions included with the kit are the best resource for this step, but I'll do a quick walk-through so you can be sure the construction is correct.
The white tube is the motor mount, the instructions give measurements to mark the tube, then cut a slot for the metal motor retainer piece. The metal piece is slid into the slot cut, then the lower motor mount ring is glued onto the motor mount. The small white ring is then glued into place over the metal retainer to hold it in place.
Then, the whole motor mount assembly can be inserted into the lower body/fin section. After that, the top motor mount ring is glued to the top of the motor mount tube, make sure the tube is centered between the top and bottom rings.
Next, glue the launch lug (the small straw piece from the kit) to the side of the tube. Make sure it is parallel to the main body tube. After that is dry, you can attach the main body tube to the lower fin assembly from the last step. Make sure the launch lug is positioned between two fins so there is no interference from the fins when you put the rocket on the launch pad.
After that, you cut the shock cord mount out of the instruction sheet and glue the elastic shock cord to the mount as shown. This is what keeps the nose cone and recovery system attached to the main body. After the shock cord mount is assembled, you can glue it to the inside of the main body using the spacing from the instructions.
Now we can move to the nose cone. Screw the metal eye screw into the hole in the inside of the nose cone as shown in the instructions. Then the parachute recovery system and the shock cord can be attached. The instructions have pictures of how to load the recovery wadding and recovery system. The instructions also have tips on fixing either a too loose or too tight nose cone. In my case it was too loose so I wrapped a layer of painters tape around the part of the cone that fits into the body tube.
Whew, we made it! Congratulations you have assembled you first rocket!
Choosing a Launch Site.
Now building a model rocket is fun, but launch a model rocket is our goal. The Estes website as well as the NAR safety code gives guidelines for how much area you'll want to have depending on the motor size you are using. In our case we are using a A series engine, these smaller engines are recommended for the first launch to ensure proper operation of the rocket and helps to guarantee recovery of the rocket. Our Alpha III is only able to reach up to 275 ft. with this engine, but again we want to make sure the recovery system works before trying to go higher. According to the resources linked above using an A engine requires a minimum of 100 Sq. ft. around the launchpad.
Some good options for a launch site:
A empty field
A football or soccer field
A large public park
Some other considerations when choosing a site:
Power lines, trees, and other obstructions - The NAR safety code part 11 says :
Recovery Safety. I will not attempt to recover my rocket from power lines, tall trees, or other dangerous places.
Permission - if you are unable to use your own yard for a launch, ask permission before using any public lands, and it goes without saying don't trespass while attempting to launch a rocket. Failure to seek permission could effect future attempts to use the area for launches.
Don't launch a rocket near an airport - not only can it violate FAA regulations, but it could lead to a unrecoverable rocket and a not so friendly discussion with a government official.
Don't attempt to launch on a windy day - This will more than likely cause you to lose a rocket, but could also cause the rocket to drift in a way that causes it to leave your secured area. This could lead to an accident caused by the falling rocket.
Setting Up Your Launch.
Now that we have a site, we can prepare our site for the launch. If you are using a public area, make sure it isn't crowded. Also, if the winds start to pick up you may have to postpone the launch. Once we have secured our site and verified the weather will cooperate, we can set up our launch pad and our rocket for launch.
First is to setup the launch pad following the instructions in the previous section on building the kit. I suggest carrying a level to make sure the launch rod is straight up and down. This will keep the rocket from drifting once it's left the launchpad. If there is a slight wind, you can counteract the drift by aiming it slightly into the wind. Keep in mind though you should not launch the rocket with the rod pointed at more than a 30 degree tilt per the NAR safety code.
The next step is to insert the igniter into the engine. To do so, insert the pointed end into the hole in the bottom of the rocket as far as possible without forcing it. Then use one of the plastic plugs to secure the igniter. Once the igniter is installed, any current across the contacts will cause the engine to fire so be careful!
Next is the launch controller. Hopefully you remembered to put batteries in it before making it this far! The launch controller has two wires with clips on them coming out of one side, and a metal rod tied to a string. This rod is the safety for the controller, and the controller won't be able to fire an igniter without the rod inserted into the controller.
String out the full length of the wire before making any connections. Make sure the either the safety key is not inserted or the batteries are not installed into the controller. Then connect the clips to the leads of the igniter, it doesn't matter which clip goes where. After that, you can install the batteries into the controller if you haven't already.
Countdown time!
Success? or Failure to Launch?
Now we are ready for our countdown! Make sure any spectators are aware that the launch sequence is commencing then begin your countdown. I like to leave the safety key out until I get close to the end of the countdown. Insert the key when ready, Then 3... 2.. 1. Push the button on your controller and after a couple of seconds you should have ignition! Then watch as your rocket completes it's burn and drifts back to earth successfully.....
Unfortunately at the time of publishing this I was unable to find a suitable day to launch my kit. I do plan on documenting its first launch and updating this once I do!
Wait... something went wrong!
Sometimes things happen! If you have a failure to launch, be calm. Remove your safety key and wait at least 60 seconds before approaching the rocket. Sometimes the igniter doesn't contact the propellant well enough and it takes a second or two to ignite. It's also possible the igniter or engine is a dud. If this is the case remove the igniter and see if it has attempted to ignite, if it has then I recommend removing the engine and pouring water on it to make sure it isn't smoldering, then discarding it. if the igniter seems to have not fired, you can try another igniter in the same engine.
Hopefully this guide has ignited a new hobby in model rocketry for you. This isn't meant to be the most comprehensive guide to the hobby, but it is meant more to remove some of the mystery if you haven't wanted to take the leap into the rocketry hobby. Again, unfortunately I was unable to launch before publishing this instructable, but I hope to be able to do so soon!