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Full Version: High Power Staging Q&A/resource thread
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I figured it would be a good idea to start a thread that is all about multistage rocket design for high power.

In this thread we will discuss how to set up a rocket/electronics for multistage use as ask and answer questions on the subject. I will also try to create links to posts of the most innovative and useful designs for electronics set up, interstage set up, sustainer set up, ect.


Booster electronics:

Sustainer electronics:

Sustainer construction:

Booster construction:

Safe practices and tips:

Unfortunately I'm away from home so I can't post anything on my existing build until tomorrow evening...
This is a great idea for a thread, and I wish I'd had it as I've built my own two stager. One tip that Jim Jarvis put in my thread on TRF was to establish safe lighting conditions for your sustainer based on reaching an expected altitude by a time rather than a delay after burnout. The reason for doing this is that there are many flight conditions where you would NOT want the sustainer to light, such as a non-vertical boost, but which might still satisfy conventional standards such as time after burnout or velocity. I'm using a Raven which makes this easy: I take the accurate finished weight of my rocket and ensure my simulation reflects how it will launch, I look at what altitude the sustainer will reach at how many seconds after launch when ideal ignition would occur, and I use those numbers as the conditions to ignite. Multiple simulations with varying degrees of wind or off-center launch are run so that I establish a safe window of operations from which I can pick those limits, so if the stack turns into the wind a little too hard my sustainer will separate, coast to apogee, and recover normally instead of firing off in an undesirable attitude.
Yes that is very true, I do a time vs altitude vs speed check for my two stage flights. Has to meet all three parameters to light.

In my opinion a Raven is the best for staging electronics right now. But if someone comes out with a new version of the tiltometer, I'll say that that is the best (plus a raven of course).
I was sitting in my shop today wondering what to do while I had some batteries charging...

Then I remembered that this thread need content (remember anyone can contribute), so I thought I might get started on it.

So I'm going to start with probably one of the most important areas to get right, the interstage.

Modified (unfinished) interstage coupler and electronics sled on a Wildman Darkstar Jr. Aft end is left.

Inside of fore end of interstage coupler. Note the thick layer of epoxy that is used to hold the bulkhead and threaded rods in place

If you have any questions about construction feel free to ask.
The sustainer.

Essentially it's a standard dual deploy rocket with a couple differences.

Difference one:
Sustainer on the bottom, booster on the top.

The fins on the sustainer are generally pushed forward in order to allow the interstage coupler to fit inside the aft end of the sustainer to securely couple the stages.

Interstage and booster coupled to sustainer.

Second difference (no pic right now)

A type of conduit (I used a brake line) is bonded to the motor mount and spans almost the entire length (notch centering rings accordingly!). Make sure one end pokes through the bottom centering ring, and the other pokes through the top. This conduit will be used to run your sustainer igniter to you av-bay.