Apogee Components Mass Driver

Apogee Components - Mass Driver {Kit}

Contributed by Moira Jean Whitlock

Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border
Manufacturer: Apogee Components
- by Moira Jean Whitlock

[Rocket Pic]Brief:  This rocket is special in that it uses apogee's 10.5mm engines and it is also designed for the payload lofting NAR competition. So, it comes with a tubular device for holding a standard payload mass, and it can fit into the payload section of the main body. It is three finned and recovers with an 8-inch chute to make tracking easier.

Construction:The package arrived from Apogee, by US mail, well protected with styrofoam popcorn, and all parts were there and undamaged. Instructions were clear, illustrated, and logical. It was easy to follow. The nose cone is solid lightweight balsa wood, and the fins are precut, rectangular, and also lightweight balsa. The chute is hexagonal, and flat and made of thin black plastic, much like trashcan plastic.  This is not to demean quality, but for description. After all, how could a nylon chute fit? And it would be too heavy. And it would be too heavy. The 6 shroud lines are nylon thread, 12 inches long, and affixed to the chute via adhesive paper donut-shaped reinforcements. The shock cord is 12 inches of 1/8 inch Kevlar® cording. There is no stretch, but since this model is for small engines, I was not concerned. 

The body tube is in three parts. The top part glues right to the nose cone and is spiral wound paper, and 3.75 inches long by .75 inches in diameter. The middle part is the same only it's 3 inches long.  There's a paper coupler between these, and only one half is glued, so that the model separates between the two parts of the main body. 

Now comes the tricky part. The bottom third of the main body is a cone made of thin cardboard, and its outline is provided. It is cut out and then glued into a cone that reduces the main body tube from 18mm to 10.5mm, as there is a 10.5 mm wound paper body tube for the engine.  This tube fits into the main body via a centering ring that also serves to anchor the shock cord aftward. The cone fitting is tricky in that handling it roughly can easily dent it. Also, I had to sight it up and down before gluing it to be sure that it was symmetrical all around.  If not, it has a slightly cockeyed look. A wound paper engine block was provided, and I placed it at a position to allow the model to take the longest of the 10.5mm engines, namely the B7's. 

There was a fin placement guide provided, and I used it to place the three fins correctly. This was a paper cutout to place around the body in order to mark it for the fin placement.

Finishing:There weren't any decals. There weren't any decals. But if you've read any of my other reviews, I'm not daunted by this. I see it as a loose football for me to pick up and run with. So, I used Monokote and silver craft paper, available at many hobby stores. I spray painted the fins yellow after sealing them with epoxy and sanding them down.  I do this to strengthen balsa and wood fins, and also to provide a glassy finish.

It's a sharp looking little rocket, but since I chose green...well, I'm glad for the chute that will help me find it. This little guy flies high.

Construction Rating: 4 out of 5

Flight:The recommended engines are the Apogee 1/4A2-4, 1/2A2-2 and 1/2A2-4, the A2-5, and B2-7. With the payload, Apogee recommends the A2-3 and B2-5. So far, I have tried the 1/2A2-2 since the parks around here are small. With just that, the little rocket was nearly gone, zinging up so high that I almost couldn't see it.  But I zeroed in on the chute and got my model back. Imagine when I try a B! It flew straight and fast. Watch this one well or you'll lose it. Prepping is easy, and I used just a couple pinches of worm bed wadding. The chute was unburnt. The chute was unburnt. Since it's plastic, I worried about that. I've seen that kind melt. I've seen that kind melt. The engine was retained with bands of masking tape around the engine overhang as well as the body tube.

Recovery:The shock cord, as mentioned, is Kevlar® string. The system was easy to assemble, with clear instructions. It worked fine without damage to the system. The recovery was slow, but with a chute, you can expect this. However, I had time to catch it, which is a rare thing.

Flight Rating: 4 out of 5

Summary:Unusual looks, easy to make. Unusual looks, easy to make. Must handle the reducer cone gently and align it well. And must protect the delicate chute from burning.

Overall Rating: 4 out of 5

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