03-02-2011, 09:26 AM
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Freeform rocketry advocate.
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Join Date: Jan 2008
Location: Claremont, CA "The intellectual capitol of the world."-WSJ
Posts: 3,780
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Quote:
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Originally Posted by Earl
The Centuri Argus kit, intro'd in the 1973 catalog (which came out in latter '72) came with the red fin can. But it did not use either the 'consumer' plastic connector or the Enerjet plastic connector. It preceded the Phoenix Bird, best I recall.
So Jerry, I guess then you are saying because of the thicker tubes used in the 1340 kit, the plastic cone and coupler in the 1340 kit were NOT the same as used in the consumer kits? I knew the plastic coupler exposed section was different between the two versions, but I didn't realize the cones were different too. I guess they would have to be due to the thicker tube walls.
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The Phoenix Bird was the first to use both the plastic fin unit and the plastic nose cone and coupler combo mold. The Centuri Argus fins are the likely source of EJ 1340 fins.
The mold on the 1340 had about the same nose cone shape but the nose base and coupler bases were smaller OD to fit the Minimax tube. The mold details were different too. The seat between the two coupler shoulders was smooth and short on EJ and visually detailed and longer on Centuri. The plastic was thicker on EJ as well. You can control the shot mass on a blow molded part. On model rockets the trick is to be as light as possible without voids.
Jerry
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