Sebastian Rocket

Description

A Tripoli level one certification rocket utilizing 3D printed components, such as:

Motor Mount
Fin Mount
Ballast Chambers
Couplers
Nose Cone*
Parachute attachment

Body tubes used are non-3D printed, made of LOC thick cardboard

With the extra weight added by 3D printing the tubes, along with the layer de-lamination likelihood, it simply does not make sense to print the tubes.

*I ended up not printing the nose cone because I had a commercially-made nosecone laying around and it was a lot easier to not have to design and print one, so boom, nosecone.

Details

Sebastian could potentially carry the first test of the Ariel Flight Control System, a system that can actively control the apogee altitude of a rocket.

This is a rough, low-opacity overview of of the motor mount design:

Not-so-obvious parts are labeled, the rest are easy enough to work out.

Components

1 × Motor Mount 3D Printed

1 × Motor Mount Cap 3D Printed (Holds in the motor, fins, and ballast)

1 × Nosecone 3D Printed

2 × Threaded Coupler 3D Printed (One for nosecone and one for motor mount)

1 × Non-Threaded Coupler 3D Printed

Project Logs

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Launch Stuff
Sir Michael II • 11/09/2020 at 20:18 • 0 comments

So it launched. It wasn't very fun. Or at least recovery wasn't. The wind was about 20-25mph. Sebastian had a 36 inch parachute. About 850 g. After measuring on google earth the drift was around 2.55 miles. After retrieving another person's Level 3 nosecone along the way, the total HIKE was just under four and a half miles. Launched Saturday, late Monday and my feet still hurt. Launch was good, got my Level one certification. 198.5m/s (444 mph), 805.8m (2643 ft). H242-10 motor. Eight foot long 1 inch rail. Honeywell Commercial Launch setup in the background.
Launch Tomorrow Morning!
Sir Michael II • 11/07/2020 at 02:38 • 0 comments

Sebastian will have his maiden flight tomorrow morning in Argonia, Kansas. Pictures and video to follow afterwards. Painted and glued everything today.
Rough Fins Mounted
Sir Michael II • 10/29/2020 at 18:12 • 0 comments

Even though two of the fin prints failed at some level (these two just aren't good enough for 500-600 mph flight), they still serve a purpose as fit tests and looking cool until I get them re-printed. Luckily the process of replacing a fin takes about 11 seconds. Unscrew the cap, slide the fin out, slide the new one in, screw the cap back on.
Image won't work, maybe later.
Parachute Attachment Cross Printed
Sir Michael II • 10/29/2020 at 01:32 • 0 comments

Printed, ready to glue in. Kevlar string runs through both holes and ties to a carabiner, which the parachute ties to as well.
First Fin Printed
Sir Michael II • 10/27/2020 at 22:12 • 0 comments

Warped just a little, fin tab bent a little, caused some fit issues, fixed.
Motor Mount Cap Finished Printing
Sir Michael II • 10/27/2020 at 20:23 • 0 comments

Fits like a glove. PLA instead of ABS.
Sebastian Virtual Mockup Finished
Sir Michael II • 10/27/2020 at 06:51 • 0 comments

I think it looks pretty slick.
Cap Design Done
Sir Michael II • 10/27/2020 at 06:50 • 0 comments

Finished designing motor mount cap, will print tomorrow.
Fin Mockups and OpenRocket Design Finished (ish)
Sir Michael II • 10/27/2020 at 05:56 • 0 comments

Reasonable stability margin and a good look, Sebastian has only a few more parts before final assembly starts. Looking around Mach 0.8 on maximum velocity and around 1,000m apogee.
Threaded Coupler Printed
Sir Michael II • 10/21/2020 at 01:36 • 0 comments

The original 35mm threaded coupler was extended to 37.5mm to work with threads leaving a 2.5mm gap between the coupler and the motor mount. Tolerance was adjusted after the first print for a tighter fit. *Quietly Laughs*