DesignThis rocket was originally conceived during the construction of the Nerd Magnet. I found myself with a short length of 2.1" PML Quantum Tube left over and during a trip to an art supply store to get aluminum tubing, I discovered green faux fur. The idea to make a furry rocket came instantly and inexplicably to mind. The sensibility of this project went downhill from there.I wanted something more simple, smaller, lighter, and less powerful than the Nerd Magnet that I could throw together quickly. Despite my desire for a quick rocket, the project sat idle for about nine months, until July of 2002 when I finally had an opportunity to pick it back up. By this time, I had flown the Nerd Magnet several times and had learned a lot from its design and construction. I was shooting for something in the neighborhood of 36" tall and about 12 oz. total weight. The 29/180 motor that I bought for the Nerd Magnet would probably be too powerful, but I could save money by buying another 29mm RMS canister and reusing the forward and aft closures. I decided on the 29/100 motor hardware which will fly on the G54W and G104T reloads. After the "successful failure" of the Nerd Magnet, the value of the detachable recovery tube was apparent, so I decided to incorporate this again. This time, however, I would just use reuseable plastic rivets to attach the recovery tube to the booster assembley. As with the Nerd Magnet, this rocket would employ a single-recovery system using the motor ejection charge. Booster Assembley: The 29/100 motor casing is less than five inches long, which is shorter than the G-10 fins I wanted, so the fins would be the limiting factor in sizing the booster assembley. I choose four of the PML FIN-B-02 fin design, which is a lot of fin for such a small rocket, but I am expecting this one to need added stability because of the fur and its stocky build. The root chord of this fin is 5". Sandwich this between two 3/16" centering rings. Putting the booster/recovery coupler immediately above the forward fin centering ring and assuming the airframe should go half way up the coupler's 4" length [and leaving 1/8" extra airframe at the aft end for a good epoxy fillet] leads to a booster airframe length of 7.5". The remaining parts in the booster assembley are the forward centering ring which sits 1/8" below the forward end of the coupler and a motor mount tube to run through the entire thing. The MMT needs to extend 2" forward of the airframe [to account for the other half of the coupler] and a bit aft to allow for an 29mm Aero-pak motor retainer flange to be epoxied to it. Motor mount tube length is therefore approximately 10". All that is missing is the recovery bridle mount point, which will come in the form of a U-bolt fastened to the forward centering ring, up and over the exhaust of the MMT. It may be impossible to find a U-bolt sized correctly for this task, in which case an eye bolt will be used instead. Recovery Assembley: This is just a simple piece of 2.1" diameter Quantum Tube. It gets attached to the booster assembley by a series of four reuseable plastic rivets. The length is TBD; it must be long enough to hold all the necessary recovery bridle and parachute, but otherwise as short as possible. Nose Assembley: The forward section of the rocket consists of a plastic 2.1" diameter nosecone with the bottom cut out. The forward recovery bridle attachment point is an eye-bolt epoxied into the front of the nosecone. The interior of the nosecone is used to store some of the recovery bridle during flight reducing the need for a longer airframe. The nosecone exposed length is 9.5". Parts List
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