The Mach Ness Monster, A 76mm Minimum Diameter Build

After my previously failed L3 attempt I decided to finally build the rocket of my dreams, an all carbon 76mm minimum diameter rocket (well except for a filament wound fiberglass VK nosecone). For the certification flight it will be flying on a Loki M1200 (a baby M) keeping it below mach 2 and around 20K. The second, and the much more interesting flight will be on a Loki M3464. Open Rocket and Rasero both are in agreement on on a peak altitude around 50K. I'm not as optimistic, but what the hell, either way this thing is going high.

Here is the preliminary design. High temp epoxy on EVERYTHING (TG 290F), 3 layers tip to tip carbon, ablative added to all leading edges, 60" total length blah blah blah..





I apologize in advance for a likely sloppy post, this will be my first thread on TRF.

I will be updating this regularly as I make progress on this build. Advice is certainly welcome. Oh and this will be for Aeronaut 2015.

Clay

How much does the rocket weigh in those sims?
The most I've ever heard of a MD 76 mm rocket going would be about 30k

No offense but, your sims seem a bit off.

JD

Whatever it does I love the name!

Current M record is held by Curt von Delius :

M-1450 [75mm] 45,328 ft Blackrock.

https://www.tripoli.org/Membership/...ngleMotorRecordHolders/tabid/125/Default.aspx


Good luck with your attempt!

Where are you planning on flying this, and what altitude above sea level is the launch site?

markkoelsch said:

Where are you planning on flying this, and what altitude above sea level is the launch site?

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Aeronaut, a launch out at Black Rock NV. It has an elevation of 3800ft.

JDcluster said:

How much does the rocket weigh in those sims?
The most I've ever heard of a MD 76 mm rocket going would be about 30k

No offense but, your sims seem a bit off.

JD

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At burnout rocket will weigh approximately 10-12lbs. Recovery weight is a little up in the air at this point. Those numbers are for a perfectly straight flight, I'm skeptical about actually reaching those numbers but it has been done before. The Loki M3464 is a 84%M in a 3" case. The current M record is 45K. I'm skeptical, but it does not seem like an unreasonable altitude to obtain. I've double and triple checked all my sims and ran it through two programs, I guess I could still be doing something wrong though.

This past Friday (4/24/15) I finished laying up the 3" carbon frame. 50" long (will be cut down later) and 5 full wraps of carbon. Special thanks to aksrockets for letting me use his mandrel.



That was the easy part.. now for the sanding :/

My right arm's never been so famous. Man, that was a lot of carbon. Im not sure I'd want to do that much again with an hour pot life.
Im going to go online and buy stock in sandpaper.

How much does the rocket weigh in those sims?
The most I've ever heard of a MD 76 mm rocket going would be about 30k

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Manny put one to 41K with a few inches of tubing in front of it. I think 50K is definitely possible with the right rocket/motor combo. That combo being a minimal flying case and an M2245.

Alex

I am looking forward to seeing this fly at Aeronaut!

Aksrockets said:

My right arm's never been so famous. Man, that was a lot of carbon. Im not sure I'd want to do that much again with an hour pot life.
Im going to go online and buy stock in sandpaper.



Manny put one to 41K with a few inches of tubing in front of it. I think 50K is definitely possible with the right rocket/motor combo. That combo being a minimal flying case and an M2245.

Alex

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What wins out: the greater mass fraction and total impulse and burn duration of the CTI, or the lower total mass of the Loki? I'd bet on the CTI in this situation...

Cutout fins today! Now it's starting to look like a rocket!

So um... How did the tube turn out? The fins I'm assuming are uni-carbon? Lastely, that rocket looks ready to rip through the air.

Nice rocket.

SinfulDarkLord said:

So um... How did the tube turn out? The fins I'm assuming are uni-carbon? Lastely, that rocket looks ready to rip through the air.

Nice rocket.

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The tube turned out great. Maybe a tad small on the I.D. though. The motor is a very tight fit and the nosecone coupler needed to be lathed down slightly.

Still, not bad considering this was my first carbon tube. The fins are indeed uni carbon, 8ply .1". They will be topped off with 2-3 layers of tip to tip carbon pretty soon. Thanks, I'm really excited to get this thing finished and on the pad!

Solarover12 said:

Cutout fins today! Now it's starting to look like a rocket!View attachment 265488View attachment 265489

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Did you make the carbon uni plate for the fins yourself, or get it from Dragon Plate or somewhere else? What are the angles in the uni layup?

MarkH said:

Did you make the carbon uni plate for the fins yourself, or get it from Dragon Plate or somewhere else? What are the angles in the uni layup?

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I bought the carbon plate from Rock West Composites. The angles are, 0,45,90,135 for the plate I am using.

Now with the fins tacked on with 5min. epoxy. Looking sexy now!

High tech beveling process.

Alex

Holee cow Alex, Best of luck on this audacious attempt. My personal opinion is folks like you who do a MD certification attempt deserve some sort of "extra credit" for a completed task.:shock::wink::smile:
In reality the building skills are that much more involved than otherwise required to complete a previously researched "collection of parts" into an L3 capable flier. Kurt

ksaves2 said:

Holee cow Alex,

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I'm not the one getting the L3 here, just the guy with the tools.

Alex

Subscribed. op:

Too bad Aeronaut is the same weekend as Hellfire (I know, 200k vs 25k = no comparison). Please bring the Mach Ness Monster to a UROC meeting so the rest of us can admire it!

75Grandville said:

Subscribed. op:

Too bad Aeronaut is the same weekend as Hellfire (I know, 200k vs 25k = no comparison). Please bring the Mach Ness Monster to a UROC meeting so the rest of us can admire it!

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I plan on bringing my rocket to the next meet, as long as I don't have anything come up I should be there. I would LOVE to fly this at Hellfire, but I really need the higher waiver :/.

Looks great!

Really like the sleek design

gerbs4me said:

Looks great!

Really like the sleek design

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Thanks! I'm still trying to decide on a paint job. :/ That's almost as hard as building!

Solarover12 said:

Thanks! I'm still trying to decide on a paint job. :/ That's almost as hard as building!

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Carbon can look really good naked!

Metalflake

UV degreads epoxy resin

jmight said:

Carbon can look really good naked!

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That's true!

flynfrog said:

Metalflake

UV degreads epoxy resin

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I will also consider that. I can't imagine UV being that big of an issue, unless I fly this rocket for years and years or leave it outside in the sun.

UV wont really matter but look at the sparkles

flynfrog said:

UV wont really matter but look at the sparkles

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Hahaha that would make it easier to find, and cool to look at!

Naked carbon looks cool, but metalflake looks cool too. Oh the decisions.