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Discussion in 'High Power Rocketry (HPR)' started by Ben Martin, Mar 4, 2019.
Sounds like no go fever here. Good for you.
Agreed. It is a hard, hard thing to say no, especially when you have invited friends and family out to cheer you on. But I have been very guilty in the past of thinking, "I'm launching no matter what!" And it rarely ends well. Thankfully, I have a much more laid back attitude these days.
You have the right approach. Bring something else you can fly so the day is not a total loss. And wait for that perfect launch opportunity.
Stainless steel is not always stronger than the zinc.
I'm using stainless steel for the ubolts, nuts, and everything else that could come in contact with the black powder ejection charge. This is just for the extra resistance that it offers, not for the strength as they are already stronger than needed. The only thing that will be zinc plated is the threaded rod in the nosecone as home depot doesn't carry a 5/16in stainless steel threaded rod in-store so I decided zinc will work.
I will be there I hope I get to see it fly. You did some great work.
Thanks, I hope all the tests go well. If not, there's always next month's launch (November)! Tripoli Houston is a great club, looking forward to the launch as I haven't been to one in months. See you there!
I managed to arrange my schedule so I’ll be at that launch. Looking forward to seeing it.
I’m planning on looking over everyone’s dual deployment setup so I’ll be curious to see yours. Finally decided the motor deploy isn’t good enough.
Looking forward to seeing you at the launch, it has been a little while. My entrance into dual deployment has been long overdue and with this rocket, single deployment (motor) is simply not an option. Good thing is that there are many experienced people at Tripoli Houston that love to share their knowledge with other members. I'm sure they would enjoy showing off their setups and answering any questions, because I'm sure I'll have some as well.
Whoo!!! I'll be there too(If my dad lets me lol). I live near there too. What motor?
October 12th, right?
Likely the K535 DMS motor. Puts it up to 3K ft with a reasonable velocity off the pad. The launch should be on the 12th.
Ok sounds cool! I have 11 days to finish building my tiny Cherokee-E which I'll launch there, along with my Star Orbiter.
If your dad lets you lol? Why wouldn't you dad let you lol? And what's that got to do with getting to a launch?
[Smartass power: Deactivate!)
I'm 13 years old. Obviously I can't drive.
But you can laugh, out loud or otherwise, and your dad's probably got nothing to do with that, nor has that got anything to do with getting to a launch. In this curmudgeon's opinion, "LOL" should be reserved for use as a comment on what someone else has done, stated, or shown, though it could apply to one's own description of a situation as in your case. It should in any case be set off from other language by some sort of punctuation. And did you really laugh out loud at the notion that you need a ride to the launch?
Interesting. I don't expect a curmudgeon to understand me, and that's okay.
Very nice thread. I have been following as I just started building mine.
I am getting 4k with that motor with the simulations in OpenRocket and Thrust curve. My weight with no motor is 223oz. What weight are you at?
Finished the nosecone bulkplate and threaded rod for adjustable noseweight.
Photo #1: Nosecone with bulkhead on.
Photo #2: Shows the 3D printed support ring and attachment points. The threaded rod is easily accessible.
Photo #3: Shows the threaded rod epoxied to the tip of the nosecone. At the end of the rod is a fender washer sandwiched between two nuts, providing a better anchor for the rod.
This was the last step before ground testing and now that it is done, the rocket is ready for testing/possible launch next weekend.
Mine is around 276oz without motor, which might go up/down once I finish the simulation. Here is a screenshot of the openrocket file. I think I had an error in the simulation as it's 4K now with the correct motor.
Actually my OpenRocket has the bug where it sets the pressure to 3mb by default which really messes up the simulation. With the correct data, the simulation comes out as close to 3100ft. I think your OpenRocket might have the same issue.
Yours is 53oz heavier as you have some heavy duty hardware. If I adjust the weight then I get similar results.
Check your atmospheric conditions when you are setting up a new simulation. I have a feeling yours is bugged and is defaulting to 59F and 3mbar pressure which greatly increases altitude.
I decided against going to the Tripoli Houston launch as the wind is coming out of the north due to the front. I will instead test the ejection charges at my house and post the results here.
Here's a map of Hearne Airport, as you can see there's a line of trees and a pretty good-sized pond to the south. I'll try again next month more prepared and hopefully the wind will cooperate.
ditto, but satisfied with what I found here. Nice work!
A high power SpaceX Starship (updated version) may be in progress, for after this of course.
I’m waiting to hear if the winds have calmed before heading to the launch today.
My logic for not coming/launching today is that with the wind coming from the north, if something went wrong during the first flight (main at apogee) it would almost certainly drift into the woods or into the pond.
Better to just wait until next month with testing already done and hope for favorable weather.
Agreed Srfrich. I expected the SpaceX Starship too. Really nice build Ben and great documentation and photos. Keep up the good work. BTW, I had to Google curmudgeon...
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