Dragon Rocketry Fat Boy XXL Build

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May 4, 2024
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Denver, CO
First time caller long time listener...

Recently picked up Dragon Rocketry's Fat Boy XL and XXL.. Haven't seen any build threads of the XXL and figured It'd be a good place to start.

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First off, great customer service over there at Dragon Rocketry. I'm in the mist of building a fleet of fat boys (my first rocket 20+ years ago) and he's basically the only place in town for 4" and 5.5" kits currently.
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The packaging couldn't have been more secure, and from the second I pulled the kit out of the box it was impressed.

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The 3D printed nose cone is the star of the show no doubt. The picture above included everything in the kit. Haven't tangled with a 3D printed nose cone yet, so not sure how I'm going to tackle the seam about half way down the cone yet, but nothing epoxy clay and a fair amount of sanding can't fix up.


Started off by stripping the MMT and tack gluing the FWD centering ring down with CA. Eventually graduated to BSI 30 min Epoxy (used it all my life and don't know anything better). Somewhere along the way I threw some Loctite on the shock cord mounting ring and shoved it in the body tube.

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I drilled small holes in the AFT ring and added zip ties for quick removal (to get filled later) in order to set the MMT tube in the way I wanted when I tack glued (and eventually epoxied) the fins.

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After a few hours of watching glue dry.. I decided I needed to see what she looked liked all together. Needless to say, as a kid who grew up on Estes Fat Boy's... I was pleased.

More tomorrow..
I apologize for the delay, got side tracked with my Level 2 build and flight…

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I built the entire fin can with the centering ring off, gave her some BSI love internally, and test fitted the AFT ring a few times to make sure everything was straight.


Some plastic filler for the nose cone and tireless sanding seemed to clean up the 3D printed nose cone pretty well.
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Tried to match the paint as best I could with Rust-Oleum. Seemed to turn out pretty nice!

Stickershock did a great job with the decals, however after a few adult beverages… the “T” got put on backwards and the “A” is out of center… will be correcting before launch.

I bought a Aerotech 54/426 specifically for this kit, planning on either a I229 or I215 for the maiden. Both should put it right about 2,000’.

She’s fitted with a 48” Fruity and should be right about 15FPS at 5 pounds loaded…

With any luck she’ll be onward and upward on the 21st out at Tripoli Colorado!