Does Anybody have experience of making Motor casings with Carbon Fiber Reinforced Polymers?

[SeaSiren33]

I would like to start experimenting with using them for higher-power motors using HTPB propellant.

Specific questions I have:

Should I buy or make a winder? If buy what is a cheap winder I can get for a good price?

What pattern of wind should I use to make the casing?

How do you attach the nozzle and forward closure to the casing?

Thank you so much! Any help will be appreciated.

 

[dhbarr]

What is your existing high power experience, and what is your research / experimental experience?

Do you have a compelling reason to think you need to fabricate your own materials?

 

[SeaSiren33]

I am just researching on HTPB propellant. I was just curious about how college teams are able to make their own casing. The reason I would like to fabricate my own materials in the future is that it is a lot cheaper than buying motor casings. I am also researching on behalf of my University rocketry team so that we are able to save money on motor casings and propellant in the future. Again, any help would be appreciated!

 

[Hobie1dog]

this was in another thread, maybe research or contact somebody in the group that has done this:
"By airframe-free I mean no body tube covering the motor casing. The USCRPL team that made the Traveler IV rocket to reach suborbital space did not use a body tube, but integrated the fins into their carbon fiber casing for their motor."

 

[dhbarr]

I am just researching on HTPB propellant. I was just curious about how college teams are able to make their own casing. The reason I would like to fabricate my own materials in the future is that it is a lot cheaper than buying motor casings. I am also researching on behalf of my University rocketry team so that we are able to save money on motor casings and propellant in the future. Again, any help would be appreciated!

You will never save money by building your own epoxy casings or by casting your own propellant.

It may appear so on paper, but unless you're doing a high volume at a high success rate, your reasonable failures will add up to a colossal timesuck.

I might recommend firstly getting some flight experience with off the shelf kits and commercial motors.

 

[Banzai88]

You will never save money by building your own epoxy casings or by casting your own propellant.

It may appear so on paper, but unless you're doing a high volume at a high success rate, your reasonable failures will add up to a colossal timesuck.

I might recommend firstly getting some flight experience with off the shelf kits and commercial motors.

....and look into the reasons why non-shatterable materials are specified for commercial motor casings. Understanding the safety ramifications is key. Starting off with with your second post and zero experience in pressure vessel design and manufacturing and wanting to use the least expensive equipment to wind casings is NOT the way to instill confidence.

 

[tfish]

@SeaSiren33

There are maybe 6 people in this forum...that have the experience to do what you are talking about.
If the college team your asking about 'that makes their own casing' is USC ?. They have been working on the "Traveler" series of rocket for about 10 or more years now. They work with professionals from the AeroSpace industry.

Neither making your own motor case, body tubes or building your own "Research" motor is an easy task?

Is "your University rocketry team" competing in Spaceport America Cup?

If so, I see your from Edison NJ..one of the rules for SAC is that teams from the united states flying solid motor or SRAD Hybrids are required to have mentors and Flyer of Record (FoR) Your motor would be in the SRAD class..which we call Research...which means your mentor would need to be a member of Tripoli (L3 more then likely) and be fluent in Research motors.

It might be best to find a mentor before getting to far along with your project.

Tony

 

[SeaSiren33]

@SeaSiren33

There are maybe 6 people in this forum...that have the experience to do what you are talking about.
If the college team your asking about 'that makes their own casing' is USC ?. They have been working on the "Traveler" series of rocket for about 10 or more years now. They work with professionals from the AeroSpace industry.

Neither making your own motor case, body tubes or building your own "Research" motor is an easy task?

Is "your University rocketry team" competing in Spaceport America Cup?

If so, I see your from Edison NJ..one of the rules for SAC is that teams from the united states flying solid motor or SRAD Hybrids are required to have mentors and Flyer of Record (FoR) Your motor would be in the SRAD class..which we call Research...which means your mentor would need to be a member of Tripoli (L3 more then likely) and be fluent in Research motors.

It might be best to find a mentor before getting to far along with your project.

Tony

Yes, 100% not starting now, just something I was looking into and caught my curiosity. I saw someone on Youtube do it along with USC and just wondered about the process. No plans to make anything for quite a while.

 

[eggplant]

Yes, 100% not starting now, just something I was looking into and caught my curiosity. I saw someone on Youtube do it along with USC and just wondered about the process. No plans to make anything for quite a while.

Was it my video?


Either way, I agree with the general sentiment of the others in this thread. I've been tinkering on the filament winder off and on all year, and the project of making a motor case with it only started when I could get the machine to reliably make quality tubes. I've already been making motors since 2017, and this was the next step for me. Lots of lessons learned from previous motors and projects were applied to this one, so it would be a really challenging place to start.

All that said, I wouldn't shy away from pursuing your goals! Being on a college rocket team is a fantastic time to develop your skills because you are typically working on university/sponsor money and have access to tools most people don't. If your goal is a composite case rocket motor, I'd start by breaking it down into parts you need to work on. First is how to make a motor, which I would start on by finding a local mentor and learning the ropes with them. Once you know how to design and repeatably make motors, you'd move onto the composite case. You could buy an xwinder if you want a somewhat off-the-shelf solution, but it still involves a ton of tuning to get it to work. Alternatively, you could clone my design as documented in this thread. Both the motor part and the case part are huge projects individually! I'd be happy to provide whatever advice you need on the research section of this forum and plan to document my learnings for everyone once I try a few more motors with this design.

 

[SeaSiren33]

Was it my video?


Either way, I agree with the general sentiment of the others in this thread. I've been tinkering on the filament winder off and on all year, and the project of making a motor case with it only started when I could get the machine to reliably make quality tubes. I've already been making motors since 2017, and this was the next step for me. Lots of lessons learned from previous motors and projects were applied to this one, so it would be a really challenging place to start.

All that said, I wouldn't shy away from pursuing your goals! Being on a college rocket team is a fantastic time to develop your skills because you are typically working on university/sponsor money and have access to tools most people don't. If your goal is a composite case rocket motor, I'd start by breaking it down into parts you need to work on. First is how to make a motor, which I would start on by finding a local mentor and learning the ropes with them. Once you know how to design and repeatably make motors, you'd move onto the composite case. You could buy an xwinder if you want a somewhat off-the-shelf solution, but it still involves a ton of tuning to get it to work. Alternatively, you could clone my design as documented in this thread. Both the motor part and the case part are huge projects individually! I'd be happy to provide whatever advice you need on the research section of this forum and plan to document my learnings for everyone once I try a few more motors with this design.

Yes! It was your video that made me look into this in the first place! Thank you for documenting your journey in developing these motor casings. I am looking forward to reading your findings once you try a few more motors! I think I'll stick to tinkering with an aluminum case for now on smaller motors and work up eventually. Will definitely reach out if I need help!