Securing the Nose Cone to the Parachute

Previously, we created replacement fins and attached them to a found rocket. Now, we need to repair the recovery system, which consists of an ejectable nose cone with a parachute attached by a flexible cord to the rest of the rocket.

On most hobby-level model rockets, the nose cone pops out of the rocket when the ejection charge fires in the engine. Thus, the fit of the nose cone needs to be balanced between being tight enough not to simply fall off, but loose enough to separate when it is time for the parachute to deploy.

My rocket sat atop a tree for a long time -- resulting in damage due to weather exposure. Either the wood in the nose cone swelled or the paper body tube shrunk -- or both. A light sanding to the nose cone restored the proper fit.

A small metal eye hook was purchased at the hardware store. The gauge is much thicker than necessary for this application, but that’s the best I could find. The downside is that the rocket won’t fly as high due to the extra weight. In this case, that turned out to be the opposite of my problem.

The hook was screwed into the existing hole in the nose cone wood. Wood glue was applied to the threads of the hook before insertion because the wood was a bit stripped from the loss of the previous attachment hook.

Elastic shock cord connected to glued-in eye hook

Elastic shock cord connected to glued-in eye hook.

The old shock cord was cracked and stretched out. I replaced mine with some elastic purchased at a craft store. However, you can get a fancy Kevlar cord and other replacement accessories online at such sites as Apogee Components.

One end of the shock cord attaches to the hook in the nose cone. The other end of the shock cord needs to attach to the rocket body in some way.

When you buy an Estes model rocket kit, part of the paper instructions include an easy-to-follow diagram that can be cut out and folded around the other end of the shock cord. The paper is then glued to the inside of the body tube. Since this is a replacement cord, I looked online for PDF instructions for any Estes kit. Then, I printed the page that included the part that can be cut out and folded.

Avery 5729 white reinforcement labels

Avery 5729 white reinforcement labels.

Apogee Components has parachutes, parachute swivels (to prevent line twisting), and replacement cotton thread. However, in this case, I liked the hand-cut plastic parachute that I found with the rocket. To repair it, I “borrowed” some thread from my wife and label reinforcement stickers from my son.

The repaired rocket is now ready to fly! Let’s take a look at the videotape...