So I was looking for rocket stuff on offer up . Found a great deal . So I received the initiator , 4" bullpup . In process of building bullpup . It says it's 4 lbs . How do I choose the correct motor for it . And how does the fins supposed to look .I'll try to post pics .
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Looks like a beast. Do you have an L1 cert?
Here's a 2.6" version.
Here's a 2.6" version.
Welcome! Nice motor cases, which ones do you have there?
Certification information here:
https://www.tripoli.org/content.aspx?page_id=22&club_id=795696&module_id=468541
This could be a good place to start:
https://www.tripolisandiego.org/
Or the NAR is a great club, too. Same certification requirements, they're bound to have a section close by.
https://www.nar.org/
Certification information here:
https://www.tripoli.org/content.aspx?page_id=22&club_id=795696&module_id=468541
This could be a good place to start:
https://www.tripolisandiego.org/
Or the NAR is a great club, too. Same certification requirements, they're bound to have a section close by.
https://www.nar.org/
Which motor cases are you referring to? The blue ones or the black ones. The blues ones are dr rockets millennium edition 2000 . They came in 38/240 38/360 and 38/480 . They are a cool color. But don't think it will matter when it's in flight .
So I reviewed the stuff you sent . Ty . It looks like I can use the rocket I'm in the process of building . Now I need to figure out what kind of recovery system to get for it . I'm familiar with rockets, the estes ones . We have a handful . The girls love putting motors in and launching . I build . They do the rest . I'm very blessed they like doing stuff like that . So recovery system I need to figure out . Any thoughts . And do you have pics of rockets you built and what level are you or have ?
The millennium cases are pretty desirable, someone was looking for them in the yard sale forum recently.
The little 29/40-120 motor will be great (!) in that Initiator, offering a nice range of flights. The G64 reload will give it a long ride.
If Estes is your frame of reference, then you and your girls are in for a real treat. It's fantastic that they like this stuff, enjoy every moment of it! Be aware, E-G motors can require a large field for recovery, so they're not usually park flyer motors.
Glad to hear you joined up with TRA- club launches are a great place to stretch your legs and watch lots of flights while feeling confident that the club has local, state and FAA covered for you.
There are a lot of ways to do recovery, wars have been fought over such things!
If a recovery system isn't provided with the kit, and if it is for that matter, I'd start by downloading Open Rocket. You'll need a good prediction for finished weight, kit specs aren't always dependable. You can build the rocket in the program, then test motors and your parachute sizes. It's free and invaluable. And, there's a huge support team right here, both programmers and expert users. Look at this thread about the latest beta version:
https://www.rocketryforum.com/threads/announcement-openrocket-version-22-02-public-beta-4-is-now-available.171295/
I'm currently a L1 flyer. I was L2 in the past, and my L2 recert rocket is ready and waiting for the opportunity to fly.
Build thread here:
https://www.rocketryforum.com/threads/a-level-2-cert-with-cardboard-build-thread.169242/
The millennium cases are pretty desirable, someone was looking for them in the yard sale forum recently.
The little 29/40-120 motor will be great (!) in that Initiator, offering a nice range of flights. The G64 reload will give it a long ride.
If Estes is your frame of reference, then you and your girls are in for a real treat. It's fantastic that they like this stuff, enjoy every moment of it! Be aware, E-G motors can require a large field for recovery, so they're not usually park flyer motors.
Glad to hear you joined up with TRA- club launches are a great place to stretch your legs and watch lots of flights while feeling confident that the club has local, state and FAA covered for you.
There are a lot of ways to do recovery, wars have been fought over such things!
If a recovery system isn't provided with the kit, and if it is for that matter, I'd start by downloading Open Rocket. You'll need a good prediction for finished weight, kit specs aren't always dependable. You can build the rocket in the program, then test motors and your parachute sizes. It's free and invaluable. And, there's a huge support team right here, both programmers and expert users. Look at this thread about the latest beta version:
https://www.rocketryforum.com/threads/announcement-openrocket-version-22-02-public-beta-4-is-now-available.171295/
I'm currently a L1 flyer. I was L2 in the past, and my L2 recert rocket is ready and waiting for the opportunity to fly.
Build thread here:
https://www.rocketryforyes I figured if I found it fun as a kid then try to get my kids and see where it goes . Whatever that puts a smile on there face . Yunno . We have alot of estes rockets. C to f engines we have flown . Here are the ones soo far . I want to get into building and launching the big ones. That is a nice rocket. How high does that go . And since I live in San Diego. I launch them off at Fiesta Island. Had To go in water twice. The kids and I love it and my wife is fine with it and very supportive. So thats a win
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Off Grid Gecko
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Like the Mean machine with the nonstandard colors. Red and black looks good on that bird and a lil easier to spot in the sky than the classic blue-white.
So first off, welcome. Joining this forum and TRA was a very good idea. I also second downloading a copy of OpenRocket at your earliest convenience. It's basically an oversimplified cad program just for rockets, and even if you don't put all the bits and pieces in there it can still tell you a lot, like where your center of pressure is on the rocket.
I assume from the Estes kits that you are familiar with CG leading CP and swing tests and stuff like that. These bigger rockets are subject to a little more from a legal standpoint is the main thing. If the rocket is over 3.3 lbs (with motor installed) then it's a class 2 rocket, so not something you want to just run out and launch in the backyard, even if your backyard is a 640acre cow pasture.
I'm not a lawyer so I won't get into the details, but TRA should send you a little packet with some hints in it about what you're getting into. Find a local club if you can and try to get out to their next launch. Bring the girls and the rockets as I'm sure they will have a rack set up for LPR and MPR. In SoCal you shouldn't have any issue finding a meetup spot.
Do you know what size tube that is installed for the motors? Does the 29 fit or the 38? That will determine the type of reload kits available. 29mm is a superb motor size for a first high-power rocket in my opinion just because it is so versatile. Estes makes a few and the reloads and single shots from Cesaroni and Aerotek run from F/G all the way to I. 38mm is great for L1/L2 certifications.
You'll also probably be using rail buttons instead of a tube mount and most likely if they came with the kit they will be setup for 1010 rail which is common at club launch sites.
Not really sure where your expertise is, but if you plan on launching that bird on an H or bigger I would suggest at a minimum reinforcing the glue joints with epoxy fillets. Might not even be necessary for H, but if it has a 38mm mount it would be a lot better for the bigger motors.
I dunno, fill in the details for us, haha. Is this your first high-power build I assume? Big rockets are super fun but they do require a bit more care in the structural setup and usually some healthy deviations from the instructions to make it a lil tougher.
So first off, welcome. Joining this forum and TRA was a very good idea. I also second downloading a copy of OpenRocket at your earliest convenience. It's basically an oversimplified cad program just for rockets, and even if you don't put all the bits and pieces in there it can still tell you a lot, like where your center of pressure is on the rocket.
I assume from the Estes kits that you are familiar with CG leading CP and swing tests and stuff like that. These bigger rockets are subject to a little more from a legal standpoint is the main thing. If the rocket is over 3.3 lbs (with motor installed) then it's a class 2 rocket, so not something you want to just run out and launch in the backyard, even if your backyard is a 640acre cow pasture.
I'm not a lawyer so I won't get into the details, but TRA should send you a little packet with some hints in it about what you're getting into. Find a local club if you can and try to get out to their next launch. Bring the girls and the rockets as I'm sure they will have a rack set up for LPR and MPR. In SoCal you shouldn't have any issue finding a meetup spot.
Do you know what size tube that is installed for the motors? Does the 29 fit or the 38? That will determine the type of reload kits available. 29mm is a superb motor size for a first high-power rocket in my opinion just because it is so versatile. Estes makes a few and the reloads and single shots from Cesaroni and Aerotek run from F/G all the way to I. 38mm is great for L1/L2 certifications.
You'll also probably be using rail buttons instead of a tube mount and most likely if they came with the kit they will be setup for 1010 rail which is common at club launch sites.
Not really sure where your expertise is, but if you plan on launching that bird on an H or bigger I would suggest at a minimum reinforcing the glue joints with epoxy fillets. Might not even be necessary for H, but if it has a 38mm mount it would be a lot better for the bigger motors.
I dunno, fill in the details for us, haha. Is this your first high-power build I assume? Big rockets are super fun but they do require a bit more care in the structural setup and usually some healthy deviations from the instructions to make it a lil tougher.
Thank u for the compliments. That was the main focus after we lost 2 in the beginning. But after seeing the big ones .they look cool with the missile looking colors . They are all cool though .
I figured that was a big boy rocket it said plywood fins . Lol . Thing is heavy than I'm used to . I'm still in process of building it .I'm using some type of super glue to get in place. Then going after with bsi 15 min . It didn't come with parachute so I need to figure that out . Which eltronics should I get .if any . Idk . Newbie remember. Lol. And the size of it is 38mm for the bullpup.
So why are the millennium blue tubes sought out . Just for looks . So please if u can explain . They are in the pics
Off Grid Gecko
Well-Known Member
Those blue tubes are actually the motors, or actually the motor housings. At 38mm most of your motors will be shipped as kits with individual grains that are loaded into those aluminum tubes, but the propellant pellets are made by manufacturers for their reload hardware specifically. I use cesaroni motors for instance, so my reloads are not used in your tubes. They all have their own specs. Also the igniters are a little different, requiring the igniter to be fully inserted through the length of the motor rather than plugged into the end of it. You'll also need to check any o-rings that need to be used and stuff like that.
Whole different ballgame when you step up to big motors. If you check out the motor kits available from apogee there is a lot of bonus information on their sales pages that will get you caught up on the basics fast, and Tim has put out a ton of instructional videos over the years that are linked from the site. It's a good place to get a crash course in modern high-power rocketry. Anything else, search the forum. Wealth of info here. Even better, go to a couple club launches and check out people's set ups, how they are loading motors, etc.
It might feel like a bit of a learning curve at first but it's really not that bad. 38mm is big motors though. I think there are a couple single-use motors that you can use right out of the packaging, more or less. But def learn what you can and the first time you launch it (I suggest a G motor) at a club launch have someone look over your shoulder or help you set it up. I'm not sure if 4 pounds is too hefty for a mid-power motor or not TBH, so there might be other concerns such as the velocity off the pad.
Hang on a second...
Peenemunde West? That's a rare kit, it was probably rather expensive new. They later became Polecat Aerospace, IIRC.
Please take your time and keep asking questions, post lots of pictures for posterity and advice. You won't find another one like it!
Rex R
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Probably get more replies to your hpr/cert questions in the high power section... Four # is kind of heavy for a G motor , figure 3.3# for a G. For a first hpr rocket many folks suggest a simple 'pop at the top' recovery(just like Estes) fewer things to go wrong. I would guess a chute somewhere around 30 - 36" would work.
Off Grid Gecko
Well-Known Member
I can vouch for that, don't go with a 48" chute and a mile high rocket for your L1 attempt if you can avoid it, lol.
Please don't ask why I would give such advice.
people are paying ridiculous prices for rare kits. sell it and buy 2 new kits with the money
Electronics are optional. At this point, I'd also suggest building it with motor ejection in mind, just like an Estes rocket.
If you plan to fly high, there should be room in the nosecone for an altimeter and maybe part of the recovery system, and it will double as ballast if it stays put up there. All that is more complication, and thus the recommendations for simple motor ejection now.
Obviously, a smaller 'chute will bring it down faster. You want to watch that descent speed with wood fins, so they don't break on impact. Use the simulator once you have a reasonably accurate final weight to figure out what size 'chute you need to keep that descent speed safe. Then, use the simulator find a motor that won't take you too high for that size 'chute- so that potential drift is kept reasonable in typical winds for the launch site.
Your 38/240-480 motor hardware will give you some great options for a conservative certification flight, and somewhat higher flights.
Yep. They're less common, so more desirable. There are other commemorative colors that are wanted as well, all functionally identical.
Ok sounds good .ty for the reply . This place is awesome . I like it here . But I'm trying to find where it says what type of rocket I have. Not fully built so can't weigh it . But it's the bullpup 4"
Ok . Will look into it . Ty for the reply .
Lol. Ok got it . What rocket would u suggest to get then . Lol . Can't wait to seewifesface . Babe . I need to get another one . Really. U just got one .i need it for my best. . Lol. This is gonna be great .
Really . Now I see this . SMH. Already started building it . Great . Rare kit and I'm building it . I hope it works great then .
Off Grid Gecko
Well-Known Member
Low and slow is good. If it's 5 pounds ... lemme calculate some rq... you want at least 125N of thrust on takeoff, up to 250N or even higher. An H will keep the total impulse down so the motor doesn't burn very long and you keep you pretty low to the ground, you just need that initial push to make sure it gets off the pad safely. For the delay prolly best to model it on OpenRocket (I call it blue-printing where I put in the dimensions and actual weights that I measure stuff plus some extra for glue/paint and check as I continue to build). Find something close without going under the reccomended delay time from the simulation.
Then schedule an L1 attempt with the local club and you can order your motor and hardware. There should be plenty of single-use motors in that size range but if you go with the aerotechs especially or LOKI you want to watch some vids and read up on how they go together.
Best thing I think is figure out when your club is flying and take the girls out with the other rockets and get a feel for how the process works from checking rockets in to the safety rules, etc.
A smaller kit with a 29mm mount would IMO give you a chance to experiment with reloadables, but... that has extra costs obv. As heavy as you say it is, you prolly will need a 48" chute.
And think ahead as you are building. Try to get a picture in your head of where everything is going to attach and how it's all going to go together, how you are going to connect the lead inside the motor tube, etc. (I can't put my hand very far in anything smaller than a 4" tube). If something doesn't look right, sort it out before you start gluing.
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