Rocketarium Trident T222-24 - Build

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For the retainer, all you need is that hex standoff, screw, and washer. Why add the time, money, and drag to make the triple-ring thingie? Other than it's fun to design and mill!
 
For the retainer, all you need is that hex standoff, screw, and washer. Why add the time, money, and drag to make the triple-ring thingie? Other than it's fun to design and mill!

Well - Because i'm a lot better with a CNC than with my own hands (lol). One still need to glue a matching standoff in the middle and even a 3/16" do not fit and it look so much better (my taste.. ).

Here is the finish result.. False carbon fiber only top and bottom layers but the core is glass fiber, the material was laying around..
 

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Updated the top tube bulkhead from the 3D printed part to Carbon/Fiberglass like the motor retainer.
Did the payload bulkhead the same way as well.

(pictures in attachment)

Here is the CAD file as it is right now:

T222-24 - Trident - B&W Ghost.PNG
T222-24 - Trident - B&W.PNG
 

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Some epoxy-ing today - I was nervous
 

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Be careful with all the modifications and additions. You are adding extra weight and potentially changing the CG of the stock rocket.
 
Be careful with all the modifications and additions. You are adding extra weight and potentially changing the CG of the stock rocket.

Thanks for the reminder, i really need to watch for that.
I don't think it will be an issue however, the rocket can carry fairly big motors (heavy).

The motor retainer is quite light, don't even pick on my scale.
For the payload bulkhead, a few grams here. The Top 3 tubes bulkhead is glued so cannot weight it but it has larger opening than the stock one and thinner so it might be a gram more.

The "transition" is probably the worst as it doesn't replace anything so pure added weight.
Maybe close to the CG so less of an impact on it and i haven't weight it but CAD say about 6g.

I wonder if i should make the motor stop (in the tubes) in the same material..
 

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You can add a short body tube of same tube spec diameters of cluster tubes probably and override mass of short body tubes to actual retainer mass. That’s what I did with a Fastback54 retainer on a L2 build for OR but that retainer was really heavy.
 
You can add a short body tube of same tube spec diameters of cluster tubes probably and override mass of short body tubes to actual retainer mass. That’s what I did with a Fastback54 retainer on a L2 build for OR but that retainer was really heavy.
I'm not sure I understand the suggestion.
You mean lengthening on the other side of the CG?
 
Ok - I had an idea and it will not make everyone happy or excited..
Let me explain what i mean...

- The rocket use a cluster of 3 motors
- So there are 3 ejection charges
- I'd like to channel only one charge to the top for ejection
- Then channel the other two to the sides
- At ejection i'll see 2 side explosions and an ejection

Please.. don't "hate" .. ;)
 
Ok - I had an idea and it will not make everyone happy or excited..
Let me explain what i mean...

- The rocket use a cluster of 3 motors
- So there are 3 ejection charges
- I'd like to channel only one charge to the top for ejection
- Then channel the other two to the sides
- At ejection i'll see 2 side explosions and an ejection

Please.. don't "hate" .. ;)

No hate, but there is one significant downside: if the one motor that is ducted to the top does not light, then you have... no ejection at all. And that is certainly a possible occurrence.
 
If the motor in a single-motor rocket does not light, then the rocket does not go up, and therefore will also not come down, ballistic or otherwise. :)

This is a unique characteristic of cluster rockets.

[never mind, seems you got it on your own.]
 
If the motor in a single-motor rocket does not light, then the rocket does not go up, and therefore will also not come down, ballistic or otherwise. :)

This is a unique characteristic of cluster rockets.

[never mind, seems you got it on your own.]
See my post just above [emoji1787]
Initially I taught that the ejection charge only would fail.

Good advice.. Might not be a so great ideas.
 
Good advice.. Might not be a so great ideas.
I think there's much more to be lost than gained by doing it.

I haven't done much cluster flying, but just from hanging out here I can see that a lot of consideration goes into accommodating failed ignitions, where less than the full number of motors starts. There are a lot of "interesting" failure modes and consequences. In general, if you have a rocket that is likely to fail catastrophically if any one motor doesn't light, then you should change your plans.
 
I think there's much more to be lost than gained by doing it.

I haven't done much cluster flying, but just from hanging out here I can see that a lot of consideration goes into accommodating failed ignitions, where less than the full number of motors starts. There are a lot of "interesting" failure modes and consequences. In general, if you have a rocket that is likely to fail catastrophically if any one motor doesn't light, then you should change your plans.
It does make sense and I'm happy I've dropped the idea here before doing it. [emoji106]
 
Well - Because i'm a lot better with a CNC than with my own hands (lol). One still need to glue a matching standoff in the middle and even a 3/16" do not fit and it look so much better (my taste.. ).

Here is the finish result.. False carbon fiber only top and bottom layers but the core is glass fiber, the material was laying around..

Looks pretty trick!
 
Ok - I had an idea and it will not make everyone happy or excited..
Let me explain what i mean...

- The rocket use a cluster of 3 motors
- So there are 3 ejection charges
- I'd like to channel only one charge to the top for ejection
- Then channel the other two to the sides
- At ejection i'll see 2 side explosions and an ejection

Please.. don't "hate" .. ;)

I was thinking the same thing. You could just run two plugged motors and one with a recovery charge.

Having never flown a cluster before, how does one deal with all three charges? Do you just let it go with all three charges or what?
 
I just run with all three ejection charges. Redundant backup if one motor fails to light. Also not uncommon for the charges to pop a split second apart from each other. So overpressurization of the main motor tube is mitigated. I haven't had a tube split from the ejection charges yet.
 
I just run with all three ejection charges. Redundant backup if one motor fails to light. Also not uncommon for the charges to pop a split second apart from each other. So overpressurization of the main motor tube is mitigated. I haven't had a tube split from the ejection charges yet.

Excellent. I was wondering about the pressure. Good to go on all three, then.
 
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