Advice on a launching solution for a mostly cone-shaped cardstock rocket

[gravityzap]

I've been working on a cardstock model of the "Stardust" rocket from Perry Rhodan, which I will be modifying in order to fly, and realized that launching it is going to be quite tricky. The problem lies in the rocket's primarily conical shape, which means I can't do a launch lug on the outside. I cant do an internal lug either, as the internal structure is much too complicated for that to work.



I'm only in the early stages of this build, so I should be able to implement most suggestions you may have for me.

As for size, it's roughly 54mm at the base, flying on Estes 13mm motors.

 

[Rschub]

* removed*

 

[les]

If you can't figure out how to modify/clear a path for an internal lug, you may need to make standoffs for an external one.
Do a two piece lug. Keep one low by the fins and the other by the lower interstage. Red is the lug, yellow is a spacer for the upper. Could use plexi to hide yellow spacer.



Only other option may be to launch from a tube with some foam pieces that fall away to keep it centered in the tube

 

[gravityzap]

If you can't figure out how to modify/clear a path for an internal lug, you may need to make standoffs for an external one.
Do a two piece lug. Keep one low by the fins and the other by the lower interstage. Red is the lug, yellow is a spacer for the upper. Could use plexi to hide yellow spacer.

View attachment 687527

Only other option may be to launch from a tube with some foam pieces that fall away to keep it centered in the tube

Might go with the tube idea.

 

[Scott_650]

A launch tower would work - probably not worth the effort to go full competition style, but four lengths of rod/dowel, two per opposing fins, mounted in a wood base with a couple of stand-off blocks should do it, I'd go with 4 foot lengths. The stand-offs would be necessary to keep from cooking the model - same as needing a stand-off on a launch rod so it won't sit directly on the blast deflector.

 

[BABAR]

I strongly like @les idea of internal lug.

Hoping you haven’t built the motor mount yet.

I don’t have a scale for the inside motor mount. Assuming it clears your shuttle at the tip, a standard lug on the outside of the motor mount will work.

You may need to put accommodating holes in the centering rings.

You will need to poke a small hole in your outer hull. It does NOT have to be load bearing. Put it on the “non-beauty” side of the rocket. Often you can pull an @neil_w and integrate the hole into the cosmetic scheme. Color it with a black sharpie inside and call it the plasma port.

A long paper soda straw works really well, especially if you have to go through centering rings and the hull,

It your BT-5 motor mount is SMALLER than the diameter of the shuttle at your cone tip, you can use a stand off and still stay internal.

Straight trails.

Looking forward to finished pics and obligatory launch video!

 

[Azamiryou]

I'd expect a single long-ish launch lug on one of the fins would work. Your thrust centerline is only 27mm away from the rod. You might need to strengthen that fin and some of the internal structure to make sure the lug is rigidly connected to the motor mount.

 

[JoePfeiffer]

I'm also surprised there is too much internal structure to find some place to put a hole for a lug...

Would a piston be practical?

 

[techrat]

This looks like a low power rocket. You can just glue a launch lug to it at the angle of the cone, and it'll straighten out after it leaves the rod. See the Centuri X-24 "Bug" flying lifting body model rocket, which is available via squirrelworks now as the X-RV. Because of the shape of the cardstock rocket, it flies off the launch rod at an angle, but will fly straight enough. Once the fins get enough air going past them to be effective, it'll do OK.

 

[cls]

If you aren't at a real NAR launch... I bet it will ROG without a rod. Banish me, I've gone rogue.

 

[gravityzap]

If you aren't at a real NAR launch... I bet it will ROG without a rod. Banish me, I've gone rogue.

What does ROG mean?

 

[cls]

What does ROG mean?

Rise off ground. No launch rod. Need big stability, like an Estes Mega Mosquito.

Slightly dangerous, don't tell anyone

 

[NTP2]

If you aren't at a real NAR launch... I bet it will ROG without a rod. Banish me, I've gone rogue.

Billy Get the tar and feathers… and tell @troj to bring his skillet..

 

[troj]

The time to solve this was probably while you were building the model.... You're going to need internal structure to hold a motor mount and recovery system anyway.

What you have is basically the same thing as the [Fliskits Nantucket Sound](https://www.fliskits.com/WPRESS/product/nantucket-sound/).

That kit has an internal tube that houses the motor mount and recovery system and the launch lug is glued to that. There's a hole below it in the bottom paper shroud as well as a hole up higher.

The Estes Mars Lander is similar.

-Kevin

 

[troj]

 

[Daddyisabar]

So many troubles with cone rockets having good looking, cool, fins on top, asymmetrical nose cones. The CP creeps up requiring more yucky nose weight and thrust (bigger, heavier motor.) Launch lug should ideally be just under the CG, being a nice long single piece or a two piece with one at the bottom. If too hard to modify make it a really really good looking shelf model and start on another one with major internal mods for a safe model rocket flight.

 

[Daddyisabar]

If you aren't at a real NAR launch... I bet it will ROG without a rod. Banish me, I've gone rogue.

No one expects the Spanish Inquisition!

 

[Daddyisabar]

View attachment 687961

Flis Kits Rock!

 

[gravityzap]

The time to solve this was probably while you were building the model.... You're going to need internal structure to hold a motor mount and recovery system anyway.

What you have is basically the same thing as the [Fliskits Nantucket Sound](https://www.fliskits.com/WPRESS/product/nantucket-sound/).

That kit has an internal tube that houses the motor mount and recovery system and the launch lug is glued to that. There's a hole below it in the bottom paper shroud as well as a hole up higher.

The Estes Mars Lander is similar.

-Kevin

I haven't built it yet.