How To Design A Solid Rocket Motor - Simplex Ep 1

Charlie Garcia is the person helping me mix and cast this motor - lots of good videos about solid rocket motors on his channel too: @AstroCharlie

0:00 - Intro
2:30 - Safety
4:04 - Parts of a Solid Motor
5:21 - Propellant Geometry & Simulation
10:14 - Onshape Ad
11:20 - Motor Case CAD
12:54 - Nozzle CAD pt 1
13:19 - O-Rings
14:23 - Radial Bolts
15:56 - Nozzle CAD pt 2
17:28 - Forward Closure CAD
19:37 - Outro

For more info:

[amessman]

As is traditional in computer networking, simplex means single way communication, duplex means dual way communication.
Naturally, your Duplex V1 engine must have thrust coming out of both sides.

[thomaskennings]

I for one would actually love an entire episode dedicated to the safety aspect of this! Not a "tutorial", but just some insights into the considerations you had to make.

[squalosus]

"Comfort gets you hurt", words to live by. Not just applicable to rocketry, but to any usage of dangerous materials or equipment.

[derMor]

Hey Joe,
I would recommend placing the pressure transducers at 135° and 90° apart. This helps in preventing pressure oscillations being invisible due to symmetric sensor placement. Would be really interesting to see if there are some modes other than the L1-mode visible in the pressure data.

[phobos]

My day is always better when BPS posts. Keep up this amazing work! Can’t wait to see what’s next

[NainKaigo]

I have built smaller scale I class motors out of PVC and there are so many things that can go wrong. Safety cannot be overstated. Even at the smaller scale, a motor exploding is exceptionally violent. Richard Nakka is a great resource for learning about designing motors on a much smaller scale.

[wesplybon]

5:15 - Joe bringing us all right to the peak of the Dunning Kreuger curve and dropping us off

[AstroCharlie]

I'm super excited to see this series Joe! It was super fun to work on this with you!

[TheThomSirveaux]

I used to work for a company that was making, let's say a very, VERY fast rocket motor for a very specific application, and one of the guys I worked with used some very expensive, very complicated software to simulate the rocket grain geometry. The company even had him fly out to the software developer to get in-depth training on how best to use it.

I still remember, and I'm very jealous of that experience he had, because simulating rocket grain geometries sounds freaking fun as hell.

[KillerDragon]

don't forget about friction between the motor wall and the nozzle retainer! In college I grenaded a motor because I only considered the fasteners. in reality the friction was carrying an immense amount of shear. factor this into your nozzle ejection calcs and measure preload on install!

[daan]

Absolutely incredible! You're such a scientific inspiration!

[polkobra]

This video is on a totally different level of quality. Your work is absolutely breath-taking and I am so excited to see more! Best of luck!

[AAerospace]

The complexity of your projects is exponential!!! Can't wait for the “I LANDED A ROCKET ON THE MOON!” video .🚀🤣🚀🤣🚀 Great video once again btw.

[sunlight]

I know the footage from space shot will be incredible, and in the meantime I’ll enjoy these updates :) keep it up!

[Oldman]

Don’t know if you are an aerospace engineer but if not you should be because you have all the qualities to become one. I was one for 40 years specializing in strength engineering. Your video really takes me back to the good old days of solving complex engineering problems. I wish you the best of luck. Take care.

[jimseibyl]

I have loved watching your journey from hobby motors to full space shot. Well done Joe!

[allkurious]

Your channel has been, and will continue to be one my absolute favorites of all YouTube.

[brodymackinnon]

The timing of this video is great because I just started my first very small scale rocket and just finished making my first test batch of ACPC. This video is a great resource!

[joakimlindblom]

Wow -- this is at a whole other level! In my youth, my best friend an I built rocket motors inspired by Estes designs, starting with cast potassium nitrate/sugar grains and then going to ammonium perchlorate/aluminum/rubber based grains. But we our designs were mostly seat of the pants ball-parking, and a result most either didn't build up enough thrust for stable flight or exploded due to overpressure in the combustion chamber, with only a few successful flights. I really admire the level of sophisticated science, engineering and dedication you're putting into this!

[mduckernz]

Nice.

I too have built up to O class, using a couple different classes of APCP - some standard R45-HTLO, some with a pre polymer polyurethane, and some with platinum catalysed silicone. The silicone burns REALLY fast btw, it’s great for end burning geometry when combined with organoiron burn rate catalysts.

Wonderful to see some rocket motor development here on YT, when I started this stuff was way less than mainstream and it’s great to see more getting into it!