I want to get into high altitude mid-power rocketry, and I have a few questions that I need answers to.

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rboom123

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My first question regards the next rocket I plan to build, which is the Estes Star Orbiter. I am going to modify it into a two stage rocket, the booster stage being 3D printed. And I will use an Estes F15-0 and an F15-8. If the projected altitude with one engine is around 1800 feet, how high should I expect two stages to take it?

My second question is more long term. After I finish with the Estes Star Orbiter, I want to get an Apogee Aspire, and launch it with an F10-8 aerotech engine that is said to take it a mile high. If I were to start launching rockets 5000+ feet in the air, and I want to recover them, should I invest in a GPS tracker? If so, which one should get? I am only seeking to locate the rocket, I don't need to know all the other stats as that makes it more expensive. If I don't need to get a GPS tracker, should I get one of those screaming beeper devices instead? Again, which one? Would a beeper even suffice for rockets going higher than 5000 feet?

Thanks for taking the time to read through my barrage of questions. Your answers are much appreciated.
 
Tracker in the nosecone, and a JLCR would be handy for the Orbiter.

Get some extra couplers to toughen up the Star Orbiters booster. Turn one into a baffle And consider gluing your shock cord inside the tube coupler before joining the tubes.
 
Tracker in the nosecone, and a JLCR would be handy.

Get some extra couplers to toughen up the Star Orbiters booster. Turn one into a baffle And consider gluing your shock cord inside the tube coupler before joining the tubes.

Unfortunately, the nosecone on the Star Orbiter is sealed. So I would have to get a different nose cone or cut this one open.

Where would you recommend putting the extra couplers?

Also, what's a JLCR?
 
I haven't tried with an SO yet, since I consider those kinda disposable. But I've been hacking the backs of nosecones off and gluing two rings in, and then bolting a disk to them. The disk has a stick on it that goes through the rings into the nose. I glue the tracker in there. Metal eyelet on that disk for cord attachment. Between the rings are Great Planes 4-40 blind nuts.

Couplers glue in with epoxy, just ahead of the motor mount tube.

Jolly Logic Chute release. It holds the chute bundled until the rocket reaches a low altitude. Barely fits a BT60 tube.
 
The answer to your first question is, "download OpenRocket, and run a simulation". Not very difficult, and something you should probably be doing if you're doing multistage midpower flights and have questions about altitude, etc. THere's lots of help here if you need it.
 
First of all, I love the Star Orbiter. I've considered 2-staging it myself.

If you want a tracker, you will need to cut open the base of the nosecone and make something to hold it. Search around here, there will be several threads describing how to mount a tracker in a nosecone. Here is an example for a 3D printed tracker mount, but it looks like it might not work with the Star Orbiter nosecone.
https://www.labratrocketry.com/product-page/tracker-sled-eggfinder-mini
As for trackers, they are going to get really expensive really fast. My suggestion is the Featherwieght system (but it only works with iPhone): https://www.featherweightaltimeters.com/featherweight-gps-tracker.html

The cheapest option will be the Eggtimer system, but you will need to assemble it yourself: http://eggtimerrocketry.com/home/eggfinder-gps-tracking-system/

I agree with the idea of using a Jolly Logic Chute Release, but an alternative might be to just swap out the chute for a streamer. You want to bring that thing down with as little of drift as possible.
 
As a rule of thumb, a person with reasonably good eyes can see a body tube of a rocket at about 1000 feet of altitude for every inch of body diameter. There's exceptions--sometimes there are crystal-clear days when you can see stuff really high, sometimes it's a little misty. Tools like a reflective streamer or a bright-colored parachute can help if you go beyond those limits. Of course, a tracker helps a lot more.

While you're at it, make sure that the F15-0 on the Star Orbiter has enough oomph to lift the rocket off the pad. 3-D printed fin cans tend to be heavier than their "normal construction" counterparts.
 
The answer to your first question is, "download OpenRocket, and run a simulation". Not very difficult, and something you should probably be doing if you're doing multistage midpower flights and have questions about altitude, etc. THere's lots of help here if you need it.
+1, to all of this
 
The answer to your first question is, "download OpenRocket, and run a simulation". Not very difficult, and something you should probably be doing if you're doing multistage midpower flights and have questions about altitude, etc. THere's lots of help here if you need it.
As Kelly and Neil concurred, run the sims, I think you will find that a 2-stage Star Orbiter on 2xF15 motors will be a bit slow off the rail even an 8' rail, at least thats what my mind sim says. The F15-0's estimated max lift weight is 15oz (per Estes), two of those are 7.38oz leaving only 7.62 ozs for the rest of the rocket, recovery, paint, glue.....so on and so forth. Run the sim.
 
As a rule of thumb, a person with reasonably good eyes can see a body tube of a rocket at about 1000 feet of altitude for every inch of body diameter. There's exceptions--sometimes there are crystal-clear days when you can see stuff really high, sometimes it's a little misty. Tools like a reflective streamer or a bright-colored parachute can help if you go beyond those limits. Of course, a tracker helps a lot more.

While you're at it, make sure that the F15-0 on the Star Orbiter has enough oomph to lift the rocket off the pad. 3-D printed fin cans tend to be heavier than their "normal construction" counterparts.
Thanks for that advice. I estimate the weight of the rocket to be 450g, +/- 50g. The max lift weigh of the F15-0 engine is 540g. Is that too much weight?
 
As Kelly and Neil concurred, run the sims, I think you will find that a 2-stage Star Orbiter on 2xF15 motors will be a bit slow off the rail even an 8' rail, at least thats what my mind sim says. The F15-0's estimated max lift weight is 15oz (per Estes), two of those are 7.38oz leaving only 7.62 ozs for the rest of the rocket, recovery, paint, glue.....so on and so forth. Run the sim.

So two engines is 7 ounces, and Estes estimates that the rocket is 5.9 ounces once it is constructed, including glue, paint, recovery, etc. That gives us about 13 ounces. I'm putting an estes altimeter in this thing too, which is 0.4 ounces. We're at 13.5 ounces now. The 3D print has to weigh less than 1.5 ounces... this is close.
 
So two engines is 7 ounces, and Estes estimates that the rocket is 5.9 ounces once it is constructed, including glue, paint, recovery, etc. That gives us about 13 ounces. I'm putting an estes altimeter in this thing too, which is 0.4 ounces. We're at 13.5 ounces now. The 3D print has to weigh less than 1.5 ounces... this is close.
Close enough an 8' rail is probably minimum launch rail length.
 
As Kelly and Neil concurred, run the sims, I think you will find that a 2-stage Star Orbiter on 2xF15 motors will be a bit slow off the rail even an 8' rail, at least thats what my mind sim says. The F15-0's estimated max lift weight is 15oz (per Estes), two of those are 7.38oz leaving only 7.62 ozs for the rest of the rocket, recovery, paint, glue.....so on and so forth. Run the sim.
Wait, Estes says the F15-0 has a max lift weight of 19 ounces, not 15. The f15-8 is the engine with a max lift weight of 15oz, but that won't be a problem once the thing is off the pad
 
SO is basically 38mm diameter and the PSII booster is basically 54mm diameter. You could make a reducer but they don't work together as-is.
 
The F-F burn is lovely - but the F15 is underpowered for a booster. You've got to build light, use a long rail, and pick a low wind way.

It's a similar situation with your Aspire aspiration - getting it over a mile is at the extreme end of it's envelope. You need every bit of performance.
I've had some luck with 6" by 12' mylar party streamers for visibility.
 
OpenRocket is a great tool for scratch builders. It will help you develop rockets or modify existing ones into great flyers. It's not difficult to learn how to use and there are several people on the forum that can help with any problem you run into.

There is also another great resource here, K'tesh's OpenRocket files. Here's one you might find interesting, post 488 (11) K'Tesh's OpenRocket Files... | Page 17 | The Rocketry Forum

I love staging and it's fairly easy to do with black powder but it has it's limits. I have a Estes PSII Majestic that I fly with the PSII booster. The Majestic is about the largest (and heavist) PSII rocket that you can do it safely with. The PSII Prowler is better but it is OOP. The 29mm black powder Estes motors are slow to reach speed and they just aren't the powerhouses you might think they would be. I have a scratch built desing two stage that goes D12-0 to C6-7 and it reaches just about the same altitude as the majestic and booster using Estes F15 motors. I'd say it's even more impressive because it is faster also. (11) Two Stage Tempest Build | The Rocketry Forum

But having said that, a two stage Star Orbiter would be fun. I would use two Star Orbiter kits and just use one for the booster. I would also not use the screw on retainers to save wieght. I would just bend up an engine hook from some spring steel (think wiper blade). You won't be able to use the screw on retainer on the upper stage because it will not allow the booster coupler to slide inside the after of the sustainer. AC Supply is a good place to find Star Orbiter kits.

Oh, and just in case you don't know ordering Estes F-15 motors is a little pricey because they incur a hazmat fee of 35 dollars. Same fee for one package or 100. They use to be so much cheaper to get when Hobby Lobby carried them. The largest motors they have now are the 24mm E12.

You know Hobby Lobby does carry the Estes Vapor which can use the E12. I wonder how high one of them would go built as a two-stage using the E12 motors? I think it's time to go play with OpenRocket.

Ah, well that didn't take too long thanks to K'tesh's files. Just shy of 2,000 feet without much tweaking. Just deleted the retainers and launch lugs from the booster.

-Bob
 
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OpenRocket is a great tool for scratch builders. It will help you develop rockets or modify existing ones into great flyers. It's not difficult to learn how to use and there are several people on the forum that can help with any problem you run into.

There is also another great resource here, K'tesh's OpenRocket files. Here's one you might find interesting, post 488 (11) K'Tesh's OpenRocket Files... | Page 17 | The Rocketry Forum

I love staging and it's fairly easy to do with black powder but it has it's limits. I have a Estes PSII Majestic that I fly with the PSII booster. The Majestic is about the largest (and heavist) PSII rocket that you can do it safely with. The PSII Prowler is better but it is OOP. The 29mm black powder Estes motors are slow to reach speed and they just aren't the powerhouses you might think they would be. I have a scratch built desing two stage that goes D12-0 to C6-7 and it reaches just about the same altitude as the majestic and booster using Estes F15 motors. I'd say it's even more impressive because it is faster also. (11) Two Stage Tempest Build | The Rocketry Forum

But having said that, a two stage Star Orbiter would be fun. I would use two Star Orbiter kits and just use one for the booster. I would also not use the screw on retainers to save wieght. I would just bend up an engine hook from some spring steel (think wiper blade). You won't be able to use the screw on retainer on the upper stage because it will not allow the booster coupler to slide inside the after of the sustainer. AC Supply is a good place to find Star Orbiter kits.

Oh, and just in case you don't know ordering Estes F-15 motors is a little pricey because they incur a hazmat fee of 35 dollars. Same fee for one package or 100. They use to be so much cheaper to get when Hobby Lobby carried them. The largest motors they have now are the 24mm E12.

You know Hobby Lobby does carry the Estes Vapor which can use the E12. I wonder how high one of them would go built as a two-stage using the E12 motors? I think it's time to go play with OpenRocket.

Ah, well that didn't take too long thanks to K'tesh's files. Just shy of 2,000 feet without much tweaking. Just deleted the retainers and launch lugs from the booster.

-Bob
The new E60 or E57 whatever it is will make the two stage for the larger rockets so much easier
 
My first question regards the next rocket I plan to build, which is the Estes Star Orbiter. I am going to modify it into a two stage rocket, the booster stage being 3D printed. And I will use an Estes F15-0 and an F15-8. If the projected altitude with one engine is around 1800 feet, how high should I expect two stages to take it?

You will need to eliminate the "screw-on" engine retainer. If you don't, it will be impossible to insert the Stage Coupler for the Booster.

You will need to use or make an Engine Hook to retain the motor at Ejection.

You will also need to trim the rear part of each fin tab ( about 1.5" ) to allow the rear Centering Ring to be moved forward. This allows the Stage Coupler on the Booster to slide into the Airframe.

Here is a STAR ORBITER build thread. It may be helpful in planning your modifications.

https://www.rocketryforum.com/threads/estes-star-orbiter-9716.134806

A two-stage build thread . . .

https://www.rocketryforum.com/threads/star-orbiter-should-i-or-shouldnt-i.141542

STAR ORBITER instructions :

https://estesrockets.com/wp-content/uploads/Instructions/009716_STAR_ORBITER.pdf

ADVICE : "Measure TWICE, cut ONCE" !

Dave F.
 
OpenRocket is a great tool for scratch builders. It will help you develop rockets or modify existing ones into great flyers. It's not difficult to learn how to use and there are several people on the forum that can help with any problem you run into.

There is also another great resource here, K'tesh's OpenRocket files. Here's one you might find interesting, post 488 (11) K'Tesh's OpenRocket Files... | Page 17 | The Rocketry Forum

I love staging and it's fairly easy to do with black powder but it has it's limits. I have a Estes PSII Majestic that I fly with the PSII booster. The Majestic is about the largest (and heavist) PSII rocket that you can do it safely with. The PSII Prowler is better but it is OOP. The 29mm black powder Estes motors are slow to reach speed and they just aren't the powerhouses you might think they would be. I have a scratch built desing two stage that goes D12-0 to C6-7 and it reaches just about the same altitude as the majestic and booster using Estes F15 motors. I'd say it's even more impressive because it is faster also. (11) Two Stage Tempest Build | The Rocketry Forum

But having said that, a two stage Star Orbiter would be fun. I would use two Star Orbiter kits and just use one for the booster. I would also not use the screw on retainers to save wieght. I would just bend up an engine hook from some spring steel (think wiper blade). You won't be able to use the screw on retainer on the upper stage because it will not allow the booster coupler to slide inside the after of the sustainer. AC Supply is a good place to find Star Orbiter kits.

Oh, and just in case you don't know ordering Estes F-15 motors is a little pricey because they incur a hazmat fee of 35 dollars. Same fee for one package or 100. They use to be so much cheaper to get when Hobby Lobby carried them. The largest motors they have now are the 24mm E12.

You know Hobby Lobby does carry the Estes Vapor which can use the E12. I wonder how high one of them would go built as a two-stage using the E12 motors? I think it's time to go play with OpenRocket.

Ah, well that didn't take too long thanks to K'tesh's files. Just shy of 2,000 feet without much tweaking. Just deleted the retainers and launch lugs from the booster.

-Bob
Wow thanks for the thoughtful response! I wonder if it’s safe to use a 3D printed engine block as the lower stage
 
Here is a question no one has ask you. Why are you taking a model rocket and converting into a medium power rocket. Just so you can say you reach a mile high. Model Rockets are cheap and light...you are building it heavy, (2 stage), and will need a tracker, because you want again, to achieve a mile high. Build your first mid power kit...try an E ands F composite engine and see if you can recover without a tracker.

But if this is what you want to do, go ahead......drop it with a metallic reflective streamer.
 
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