Need help with Parallel Boosters

Hi everyone,

I would like to build a rocket with parallel boosters using high power motors. I searched the forum as best I could and did not find much when it comes to high power. I would especially like to see release mechanisms, and boosters retention device.

Does anyone has made one? I only saw two threads: one from
Heli Hacker (and his hellraiser rocket) and another (with videos) from ukrocketman site. My only fear is not having a strong enough mechanism to hold the power of high-power booster motors.

The boosters would use 38mm motor mounts and the central rocket would use a 54mm motor mount.

I will also use a raven2 to detect boosters burn out, and I would use other channels to drop the boosters.

Any comments, pictures or questions are welcome.
Angara rocket:

https://www.raydunakin.com/Site/Staging.html Check out his book it has the details on a great parallel staging setup. It has a forward hook attached to the main rocket that is trapped by the booster nosecone. There is also a pivot on the core, and hooks on the tail of the boosters that allow them to fall away.

Looks like you can order the book from ARA press- https://www.arapress.com/staging-high-power-rockets/

kj

I'm already having the parts that Ray use to sell. A friend showed me them and gave them to me so I can reproduce them. They just don't look strong enough, and they rely on boosters motors ejection. I would rather use a central device that release the two boosters at the same time within the main rocket .

The Hellraiser drawings https://www.rocketryforum.com/showthread.php?41657-Parallel-Staging-Motor-choices-and-designs&highlight=parallel+staging shows only a shear pins to retain the boosters connected to the central body. I'm not sure they will sustain high thrust "shock" from a 38mm 6grain. If the shear pin break while in thrust, this booster will go somewhere else without any fins.

I will however, order this book,
Thanks!

If anybody have an idea, please share it!
Steeve

Paging Kevin Trojanowski. If I recall he has done a fair amount of this type of staging.


Mark Koelsch
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Its been a number of years but I did this on Freeze Frame https://www.rocketryphotography.com/rockets/RocketsFreezeFrame.html There doesn't seem to be a diagram of the booster dropper but its a simple device. A video of the testing can be seen here https://www.rocketryphotography.com/rockets/FreezeFrame01.avi

I successfully flew this design on K700 motors and in one case without the main motor lighting off the pad...

Thanks for your answers, it is very appreciated. Unfortunetely, we can't use black powder OUTSIDE the airframe. I had already done one, but my club is not comfortable with this idea, for now. I'm working on a mechanism with a central piston and screws attached to that piston. The screws will pass through the airframe in a slot. The boosters have small pieces of metal with a keyhole pointing upwards. This way, when the Raven ignite the black powder, the piston will rise and will release the boosters. At least I hope so ... I have to try this weekend.



But I'm still open to any other releasing mechanism!
Doug, your Freeze frame is awesome!

Kevin (Troj on forum) used modified nylon screws. They were drilled , filled with an ematch and Bp, and sealed.


Mark Koelsch
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