L3 Cert Project - Experiencing a Significant Gravitas Shortfall (Formula 200)

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Recovery hardware. I got 2 beautiful customer made harnesses from Teddy at One Bad Hawk. The new tubular kevlar material is AWESOME. 4000lb break strength. The main harness is 10ft. The Drogue is 35ft. The forged eyebolts are some of Teddy's 3/8in bolts, polished stainless as are the 5/16in quick links. One eyebolt for the nose and the other for the main attachment. Drogue harness will attach to the ARRD anchor shackle.


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Main eyebolt epoxied in and torqued down to right torque setting. Used a fender washer on the back to distribute the load on the plate.




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Shots of Nosecone coupler construction. A few notes:


  • The coupler is NOT epoxied into place. It is held in place by 6 PEM nuts sized for #8-32 screws. You can see the nut installation in the first pic before epoxy.
  • The bulkhead is installed BEHIND the PEM nuts and epoxied into place with fillets on both side. The PEM nuts also get a fillet (you can see this in pic 2). This mounting means the bulkhead has to break the epoxy fillet and shear the screws to pull through (or break in half). Neither is likely.
  • The nosecone eyebolt was installed and epoxied into place in the same way as the av-bay eyebolt.
 
Brian (Ravenex) was kind enough to rush a custom camera shroud to an action cam to me. Products been great so far. Here's the installation.
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Triple measured the can mount was not going to occupy the same space as the av-bay. I am good by 1.5in.
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Drilled according to the template. Did the shroud cutout with a dremel and touched it up with my file set. This is a dry fit. The holes end up being about 1/16in too wide on the template. I ended up turning them into slight slots. That's fine cause the screws cover the slots completely.
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Dry fit the shroud in the hole with the camera carrier installed. I needed to cut off part of the wing to make it work. That was planned as Brian doesn't have the molds for a 8in shroud yet.
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Final fillet and installed shroud picture. When the picture was taken, I had to go back and clean the fillet up with the file.
 
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The Av Bay sled fresh off the 3D printer. You can see the battery bay and cover in the back. Mounts for an RRC3 and Eggtimer TRS altimeters plus 2 screw switches on the wing.

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Full stack picture. This thing is a monster! This is before it went off for painting. My cousin is hand painting the rocket and it's going to be wicked cool.
 
Looks great! That is a decent sized rocket!

Now you need to find an old office chair and make a stand so it can take pride of place somewhere on display .
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This one is a 98mm casing bolted on with an adaptor.
 
Looks great! That is a decent sized rocket!

Now you need to find an old office chair and make a stand so it can take pride of place somewhere on display .
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This one is a 98mm casing bolted on with an adaptor.

I like that. I am assuming the case comes off the base when you want to fly it? As far as displaying it, I would love to display it in the foyer, but I don't know if my wife would appreciate the look and sweet smell of burned AP every morning...

Preview on the paint job: Mountains fading into starscape with the solar system planets on top fading into either the sun or a nebula at the nose.
 
N1000, not N10000. I don't think I would put the N10,000 in this rocket without going back and doing tip to tip on the fins.

Oh!

Is 1000 N enough thrust? I don't think I would put something with less than 1600 N of thrust in it.
 
but I don't know if my wife would appreciate the look and sweet smell of burned AP every morning...

My Nike Smoke sits on this in the stairwell and gets complaints weekly. It is still there :)

Yes, the casing unbolts for flying. I have done other stands using the vertical part of the chair and spacers (that look quite similar to centering rings!).
 
Oh!

Is 1000 N enough thrust? I don't think I would put something with less than 1600 N of thrust in it.


Possibly. For a 65lb rocket my chart says 1150 is marginal and 1500N is safe (safe being >= 5:1). That assumes standard launch rail lengths though and a longer rail should change the equation. If I sim it with the N1000 off of a rail with 13.5' feet of travel (assumed a 15' rail and subtracted the 16in between the back and middle button) velocity should be ~54 fps, which is adequate. It would limit launch to winds 10mph or below, but it's doable. Though before I would do anything I want to have at least one person double check the calculations.

I have not gotten that far yet. I know that for LDRS the motor is going to be the cert motor is going to be a 75mm 5grain M1810 and I also have a M1939 I might use.

It can handle that easily.....no further work. [Fins are 3/16 right?]:dark:

Very true. Fins are 3/16 and it has the 1/2in thrust plate on it so it should be more than fine.
 
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Fuel away. I got a 20' x 12in diameter project up next.

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The painting has begun. Sneak preview from last week. I love the mountain ranges on the fins. Nose cone is the start of a nebula.

Note, I can't paint. I do 30' paint jobs at best. Fortunately, my cousin Arti jumped at the chance to paint this. It's all going to be hand painted and totally awesome.
 
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The painting has begun. Sneak preview from last week. I love the mountain ranges on the fins. Nose cone is the start of a nebula.

Note, I can't paint. I do 30' paint jobs at best. Fortunately, my cousin Arti jumped at the chance to paint this. It's all going to be hand painted and totally awesome.

I tip my hat to you and Don Reago. I hate paint!
 
One more clear coat of go, but the painting is pretty much done. I just had to take some pictures... It's all hand painted. Starting to get incredibly excited!

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Man is that a smokin paintjob..
Good for you man...
Everything is going to go perfectly on the flight,,
just you wait and see..

Teddy
 
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