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bluefin

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What would be a good first high power two stage kit? I have found kits from Public Missiles -Quantum II, RRDS - Orion, and US Rockets makes a number of kits. Does anybody have experience with these kits or can recommend another one?
 

MaxQ

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What would be a good first high power two stage kit? I have found kits from Public Missiles -Quantum II, RRDS - Orion, and US Rockets makes a number of kits. Does anybody have experience with these kits or can recommend another one?
All good.
The Quantum Leap is a perennial favorite.

Thunder and Lightning was a good one too.

One thing to remember is motor length...some two stage kits will need modification to handle the ever increasing choices of motors...you'll want to check the rocket booster and sustainer lengths and adapters as well as individual motor case lengths for the motors you want to use both today,...and tomorrow.

I take it you have already have considered what electronic devices you'll want to do the staging, be it a timer (Perfectflite or Xavien or Adept for example) or booster motor "burn out sensor"...(like the GWiz).

I actually like the Cosomodrome Aero Bee High..it is a good way to start composite staging at a smaller size and cost, although it is a very tight fit up front for a GWiz - (but I made it work).
 
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JimJarvis50

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What would be a good first high power two stage kit? I have found kits from Public Missiles -Quantum II, RRDS - Orion, and US Rockets makes a number of kits. Does anybody have experience with these kits or can recommend another one?
I think you've shown excellent taste doing your first post on two-stagers! They are a lot of fun.

I started with the Quantum Leap, so it's the only one on your list that I can comment on. It is the shape and size of a generic 3" two-stager, but the kit has many problems in my opinion. I would list the top ones as flimsy fins (the Q-leap is famous for this), a poor method of lighting the sustainer (the motor should be lit from above and not from the booster), and the CPR system is a dead-end fork in the road of rocketry (in my opinion, having been down that road).

I got the kit and then made many changes to it. Unfortunately, I didn't go far enough in beefing up the fins and I shredded it (if you've seen the US Bakula video, which is a Q-leap, that's what my rocket did, except it didn't survive). So I rebuilt what looked to be the Q-leap, because the general idea is fine, except with dozens more changes to the kit design:

http://www.dars.org/contact.html

I have flown it perhaps 20 times as high as 18K and I really enjoy this rocket. My suggestions to anyone starting two-stagers (who have sufficient experience with single stage designs) is to get the plans for these two stagers and study them, then ask a bunch of questions, then build what you want scratch. There's lots of info out there on the Q-leap to learn from.

Jim
 

hardinlw

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I have the PML mini BBX with the Terrier booster. I flew the BBX several times as single stage to get used to the altimeter-based deployment before attempting two-stage flight. It is absolutely essential that the sustainer have altimeter-based deployment in case the engine does not light. I've flown this rocket as a two-stage twice. In both cases, the sustainer was almost horizontal before it lit and the resulting flight was a low arc with the drogue deploying almost immediately after burnout. There were two different reasons for this type of trajectory. On the first attempt, I had set the staging delay too long. On the second attempt, I had the staging delay correct, but the engine chuffed instead of lighting smoothly. In both cases the altimeter deployment saved the rocket from any damage.
 
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