3D printed rocket contest at MRRF!

[Jimustanguitar]

It's that time of the year again... Are you making plans for MRRF?
http://midwestreprapfest.org/

The MakerHive would like to host a 3D printed model rocket competition during MRRF!
http://makerhive.proboards.com/thread/8 ... -challenge

We'd like to figure out 1 or 2 class specs, are going to work on a telemetry payload, are investigating homemade engines, etc. Currently, our ideas for judging and prizes would be:
Coolest looking Rocket
Most Epic Launch
Most Epic Fail
Highest altitude
Most creative recovery mechanism

Please post any ideas that you have. I think this will be a really neat event, but we need help figuring out the specifics so that it's a fun and fair competition.

Would you be interested in an event like this?
Should we require that the rockets be printed during the weekend, or does this not matter?
Has anybody already worked on a telemetry package?
What about a camera payload?
Off the shelf engines, or homemade?
What should the prizes be?

If you can't attend, maybe we can get volunteers at the event to print your design so that you could still enter and compete...

[Chrissi]

Subclass: non-fuel powered rockets, entire rocket, launcher etc has to be printed except nuts bolts screws for assembly. Propulsion limited to mechanical means such as springs, bungee, surgical tubing.

[Jassper]

I'm thinking extra points if it is printed during the event - Part of the fun is printing it and then using it with little to no "after work" and trouble free printing.

[Jassper]

Subclass: non-fuel powered rockets, entire rocket, launcher etc has to be printed except nuts bolts screws for assembly. Propulsion limited to mechanical means such as springs, bungee, surgical tubing.

I like it
What about compressed Air propulsion?

[BenTheRighteous]

Off the shelf engines, or homemade?

Two thoughts...
1. From a n00b's POV, would a homemade engine not be much more likely to explode?
2. From a n00b's POV again, I wouldn't know squat about building an engine, so I'd probably be discouraged from entering if I felt someone else would have an advantage there.

I think you can tell which option I favor.

[Jassper]

Off the shelf engines, or homemade?

Two thoughts...
1. From a n00b's POV, would a homemade engine not be much more likely to explode?
2. From a n00b's POV again, I wouldn't know squat about building an engine, so I'd probably be discouraged from entering if I felt someone else would have an advantage there.

I think you can tell which option I favor.

Just to clarify, Homemade engines and purchased off the shelf engines would compete separately.

[Chrissi]

Subclass: non-fuel powered rockets, entire rocket, launcher etc has to be printed except nuts bolts screws for assembly. Propulsion limited to mechanical means such as springs, bungee, surgical tubing.

I like it
What about compressed Air propulsion?

Only if source of compressed air was printed

[teoman]

You might be able to print a pressure vessel. If that carbonfiber filament is as advertised.

but would not like to go near one :)I

[Jimustanguitar]

After our weekly meeting the other day, we think that there will be a C engine class, and an unlimited class. We can do a bulk buy on some C11 engines that include igniters, wadding, etc, and we can make that part of the entrance fee. The unlimited class could use whatever you want.

Should the C class use an off the shelf motor mount, or is it more fun to just print your own?

[Jimustanguitar]

Has anyone here ever called the FAA about a rocket launch before? Are they open and receptive about it, excited that you're an aerospace enthusiast even, or is it a difficult process that they generally don't want to be a part of?

[Chrissi]

A lot of it is simple common sense, designate a safety officer to make sure the area is safe before each launch and scan the sky. It would be prudent to check the nearest airfield and talk to the operator of the facility to make sure there is not a jump school or that the area is not used as a student pilot practice area, also have them look on a local chart to verify that a Victor Airway (sort of a designated highway lane in the sky) does not go over the place you have in mind. All of that shows due diligence and may cover your butt since this is part of an event.

[bot]

Get a cheap radio (audio, walkie-talkie radio), some old army fatigues and launch the rocket in the middle of the night without telling anyone. The radio is to say things in a funny chinese or russian accent pretending that you're commanding a nuclear sub.

That's what due diligence is, right?

[geneb]

Bot, I like the way you think.

g.

[Jimustanguitar]

Here's a collection to start getting you in the mood.

http://www.thingiverse.com/jimustanguit ... ns/rockets

[comds]

As one of the primary reasons to get a 3d printer was to complement my rocket designs, I will defiantly have something for this.

[Jimustanguitar]

As one of the primary reasons to get a 3d printer was to complement my rocket designs, I will defiantly have something for this.

Awesome!

This post was an idea that didn't come to fruition at last year's event. Maybe we should revive the idea if enough people are interested this year.

[bot]

3D printed water rocket would be cool.

[U.S. Water Rockets]

3D printed water rocket would be cool.

We've been working on something like that for a while now...

[youtube][/youtube]

[youtube][/youtube]

[youtube][/youtube]

[CaptainMerica]

My family used to be big into fireworks, (Don't worry we have an ATF license to do this), and my brother and dad used to really be into rockets, and to answer the question, yes, sometimes there is a spectacularly frightening explosion. But that's why we would always produce a batch of rockets made exactly the same, test a few, and determine whether the rest were good or not.

We never did anything professionally, shows or whatnot, just jumped through all the hoops for our own entertainment. I doubt I have much to offer for this competition but here's an interesting video of some of the earlier tests with different whistle/strobe mixes.

enjoy-



Pete

EDIT: I don't know how to imbed the video all pretty

[Jimustanguitar]

I don't know how to imbed the video all pretty

Usually I copy the URL from the address bar and remove the S from HTTPS to make it work. Sometimes when it doesn't work that way, I've discovered that there's an ampersand (&) sign near the last 3rd of the URL or so, and cutting it out and everything after it usually does the trick.

So take ""
and make it ""
put that inside of the youtube brackets, and it works.

Don't feel bad, it's not intuitive, and there aren't instructions anywhere. There are more ways to do it wrong than right, and it's not as easy as the other forums that I'm on.

[youtube][/youtube]

[Sheaffer]

Has anyone here ever called the FAA about a rocket launch before? Are they open and receptive about it, excited that you're an aerospace enthusiast even, or is it a difficult process that they generally don't want to be a part of?

For general model rocketry launches an FAA waiver is not required. That said, there are restrictions related to launching near airports - also think about trees, power lines, occupied buildings, etc. For high power / amateur rocketry launches an FAA waiver may well be required.

Both the NAR and TRA (the two US rocketry associations in the US) have very specific safety codes regarding launches by their clubs. A read through these codes should give you all a good sense of safety issues. While rocketry is VERY safe if the rules are followed, it is an inherently dangerous activity. There was what I believe to be the first model rocketry related death last year at a boy scout event. Read the safety codes, understand them and follow them - no exceptions.

http://www.nar.org/safety-information/m ... fety-code/
http://www.tripoli.org/SafetyCode

With respect to making / buying engines, unless you REALLY know what you are doing (as in have spent serious time studying the chemistry and physics), I would strongly recommend buying motors. They are a few bucks for A - D motors and larger reloadable and single use motors are available for sale from any number of suppliers.

If anyone is thinking about making their own motors, one of the best sources of basic info is can be found at the site below.

http://www.nakka-rocketry.net/

And a good source for engine components is here:

http://www.rocketmotorparts.com/

Hope this helps some of you all.

BTW, this is what happens when you do it right...Swiss Missile 2 (12 ft tall 6 in diameter Talon) on its way to ~15,000 ft

[Eaglezsoar]

Man that picture of the 2.5 foot rocket taking off is impressive!
I would like to see that one in person!

[Sheaffer]

Man that picture of the 2.5 foot rocket taking off is impressive!
I would like to see that one in person!

It's actually 12 ft tall with a 6 inch diameter. If you are on the East coast, check out the launches at the Maryland / Delaware Rocketry Association (especially their Red Glare event in Spring):

http://www.mdrocketry.org/

You will see some of the biggest, fastest, baddest rockets in the U.S. (short of going out to the Nevada salt flats).

[Eaglezsoar]

Man that picture of the 2.5 foot rocket taking off is impressive!
I would like to see that one in person!

It's actually 12 ft tall with a 6 inch diameter. If you are on the East coast, check out the launches at the Maryland / Delaware Rocketry Association (especially their Red Glare event in Spring):

http://www.mdrocketry.org/

You will see some of the biggest, fastest, baddest rockets in the U.S. (short of going out to the Nevada salt flats).

Sorry, misread it. 12 ft tall just makes it even more impressive. Those must be a one shot deal because I can't believe they could be recoverable.

[Sheaffer]

Man that picture of the 2.5 foot rocket taking off is impressive!
I would like to see that one in person!

It's actually 12 ft tall with a 6 inch diameter. If you are on the East coast, check out the launches at the Maryland / Delaware Rocketry Association (especially their Red Glare event in Spring):

http://www.mdrocketry.org/

You will see some of the biggest, fastest, baddest rockets in the U.S. (short of going out to the Nevada salt flats).

Sorry, misread it. 12 ft tall just makes it even more impressive. Those must be a one shot deal because I can't believe they could be recoverable.

I generally get them back. Especially the big ones like this - they are a pretty big "investment" both dollars-wise and time-wise. Either GPS or other tracking methods help a lot.

I actually got this particular rocket back one time 3 miles from the launch site after the main chute deployed at apogee (it's not supposed to).

Big rockets like this use a dual deployment system. An altimeter senses when the rocket reaches zero acceleration (apogee at the top of the ascent) and then fires a charge that separates the rocket and deploys a small parachute. The rocket then drops quickly, but under control, to a pre-set altitude. Then a second charge is fired and the main chute(s) are deployed, slowing the rocket so that it is not damaged when it lands (theoretically). The idea is that while the rocket is dropping quickly, it has less chance to drift too far from the launch site.