I am building my super Dx3 mad cow rocket except I noticed there is no positive motor retention. As in there is nothing stopping the motor from shooting through the body tube. Is something needed? Also if the shock cord is secured from the eyebolt on the motor mount all the way up to the payload section. What is holding the nose cone secure to the top of the payload section? Can I just use plastic rivets to secure it?
Superdx3 madcow help
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Titan II
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Any motor you will ever use in the DX3 with will have a thrust ring.
to the forum. Yes you can use plastic rivets to secure the nose cone.
I'm not sure about the Super DX3, does it have an altimeter bay with switch band and a payload tube separate from the booster tube with the fin can? I thought it was just the one body tube and nose cone.
Where is your apogee and/or main deployment? Where does the rocket open? The standard DD configuration would connect the booster section to the av-bay with the payload tube attached to the upper av-bay and a drogue chute attached to that shock cord. The nose cone would be attached to the upper part of the av-bay and the main parachute would be on that shock cord. Usually use shear pins to hold the nose cone on during flight, but it comes off to deploy the main chute. Many use rivets to hold the payload tube to the upper shoulder of the av-bay.
Where is your apogee and/or main deployment? Where does the rocket open? The standard DD configuration would connect the booster section to the av-bay with the payload tube attached to the upper av-bay and a drogue chute attached to that shock cord. The nose cone would be attached to the upper part of the av-bay and the main parachute would be on that shock cord. Usually use shear pins to hold the nose cone on during flight, but it comes off to deploy the main chute. Many use rivets to hold the payload tube to the upper shoulder of the av-bay.
Spitfire222
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Yes, the cardboard super DX3 has a separate upper payload tube.
Here's a useful article from Apogee: Motor Retention. For this size rocket, the motor have thrust rings that contact the bottom end of the motor tube, preventing it from shooting up into the rocket. There are various ways to hold the motor in place from falling out: threaded retainers, clips, and even just tape.
Securing the nosecone depends on what you want to do with the rocket. If you only ever want to fly it in single-stage, motor eject mode, you could glue the nosecone to the upper body tube. Or, as others have mentioned, use plastic rivets to hold it on. This allows you to fly as motor eject at first, but gives you the option of converting it to dual-deploy in the future. Good luck
