2 staging

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dazza98

dazza98

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hi guys, just wondering about doing a 2nd stage, neve interested me before until I decided I want to go high, I mean 80000ft high.

so I am wondering what electronics people use how do you couple them together motor retention tracking both stages ect just want peoples experience what worked ect.

also I have been told trying to get radio frequency through carbon fibre air frame is difficult, what have people done to over come this.

thanks in advance.
 
For anyone who wants to go extremely high or fast, the answer is to find a club near you and meet folks.

They're the ones that can help with a large number of things on your way to L3, which you'll very much need.

Happily, you should also have a lot of fun along the way, as well as getting to see a lot of gear without having to buy the wrong stuff up front.

For extreme flights, try and find out if any local club members are planning on attending a major regional event and see about meeting them there.
 
This is a massive undertaking. Get yourself an Aerotech or Estes PS2 kit, build it well, stick a baby H in there and you will be making a solid first step.
 
Just to point out the obvious...

The OP is ARA L2.
 
scsager said:
Just to point out the obvious...

The OP is ARA L2.
Click to expand...

LOL. Yeah, I think doing an Estes PS II is a huge step backwards for a L2.
Of course maybe that Estes suggestion was a humorous response...to point out a little more info is needed to give advice here.

That said, a little more on the OP experience certainly wouldn't hurt.

What electronics has he used, what construction techniques for high power has he used to date....that kind of thing.
 
Last edited:
No, I missed that. Sorry, I am frequently blind to signatures, and some of the questions read like we should start at the beginning.
 
Staging isn't particularly hard, but is certainly a fun and exciting challenge. The key things to focus on are safety and reliability.

For safety, I suggest you employ more sophistication than a simple timer activated by a g-switch or break-wire. Using an accelerometer altimeter like an AIM Xtra, Raven, or Telemega will permit you to use a few safety features such as altitude lockouts, tilt lockouts, velocity lockouts, or any combination thereof. For example, my 2 stage flight yesterday would only stage if the Raven sensed burnout and the rocket was greater than 400' in altitude after a 1 second coast. This ensures that the rocket is substantially high in the air and eliminates ignition in the case of a CATO or instability. Furthermore you can employ a Telemega to lockout your rocket based on a severe tilt angle, eliminating waiver cylinder concerns.

By reliability, I primarily mean 2nd stage ignition. Seeing as you're from Australia, you're probably flying commercial motors. Using CTI motors that use an ignition augmentation pellet will greatly simplify igniting the second stage motor. Using Aerotech or others will require that you either fabricate your own pellet, or use a hopped-up e-match to light the motor. For my 2nd stage motor I used EX motors, so I was able to use a freshly cored motor lit by an e-match and a Pyrodex pellet jammed in the upper grain. This led to an almost instant-on ignition of the relatively small 29-2G EX motor.

I urge you to give a smaller 2-stager a try, maybe 29mm-29mm, 38mm-38mm, or 54mm-38mm. This will get you familiar with your electronics of choice and confirm that you're able to execute your desired flight profile before going for the bigger attempts.
 
Funny: everyone else missed the L2 in the sig. Me: "okay, 2 stage to 8000 feet. Why is everyone acting like this is such a big....oh. 80,000 feet. Well. Um. Good luck!"
 
MaxQ said:
LOL. Yeah, I think doing an Estes PS II is a huge step backwards for a L2.
Of course maybe that Estes suggestion was a humorous response...to point out a little more info is needed to give advice here.

That said, a little more on the OP experience certainly wouldn't hurt.

What electronics has he used, what construction techniques for high power has he used to date....that kind of thing.
Click to expand...

RRC 2 Marsa 4 and 54 bee line Have built and flown many L3 rockets but I find using sticky tape is the best to hold on fins. I remember why I stopped using this forum now I ask for advice and get laughed at. shame on you guys.
 
patelldp said:
Staging isn't particularly hard, but is certainly a fun and exciting challenge. The key things to focus on are safety and reliability.

For safety, I suggest you employ more sophistication than a simple timer activated by a g-switch or break-wire. Using an accelerometer altimeter like an AIM Xtra, Raven, or Telemega will permit you to use a few safety features such as altitude lockouts, tilt lockouts, velocity lockouts, or any combination thereof. For example, my 2 stage flight yesterday would only stage if the Raven sensed burnout and the rocket was greater than 400' in altitude after a 1 second coast. This ensures that the rocket is substantially high in the air and eliminates ignition in the case of a CATO or instability. Furthermore you can employ a Telemega to lockout your rocket based on a severe tilt angle, eliminating waiver cylinder concerns.

By reliability, I primarily mean 2nd stage ignition. Seeing as you're from Australia, you're probably flying commercial motors. Using CTI motors that use an ignition augmentation pellet will greatly simplify igniting the second stage motor. Using Aerotech or others will require that you either fabricate your own pellet, or use a hopped-up e-match to light the motor. For my 2nd stage motor I used EX motors, so I was able to use a freshly cored motor lit by an e-match and a Pyrodex pellet jammed in the upper grain. This led to an almost instant-on ignition of the relatively small 29-2G EX motor.

I urge you to give a smaller 2-stager a try, maybe 29mm-29mm, 38mm-38mm, or 54mm-38mm. This will get you familiar with your electronics of choice and confirm that you're able to execute your desired flight profile before going for the bigger attempts.
Click to expand...

thanks mate that is what I was asking for not for people to take the piss out of me. appreciate the advice.
 
dazza98 said:
RRC 2 Marsa 4 and 54 bee line Have built and flown many L3 rockets but I find using sticky tape is the best to hold on fins. I remember why I stopped using this forum now I ask for advice and get laughed at. shame on you guys.
Click to expand...

Look mate, all I saw was a name I didn't recognize, no background information, 80k ft, and tell me about electronics.

Since that happens all the time, I gave the standard response. Sorry I ruffled your feathers. I don't have the expertise for the big goes, just enough to hopefully help with the usual.

I'll probably make the same mistake again in the future, but I'll keep trying :). Cheers.
 
I have to ask

"using sticky tape is the best to hold on fins"

What are you using? I use 3M VHB in a wide variety of abusive situations, however I never considered it to hold on fins in flight. Please elaborate on this application.
 
Hi Dazza,

On your other questions, yes you cannot have your tracker antenna inside a CF airframe. If your nosecone is fiberglass you can put the tracker there. Or you can mount your beeline to the recovery harness and run the antenna wires taped to the hardness. Then you will be able to receive the RF after separation. However if separation fails then you are out of luck.
 
Take a look at my thread Workbench 2.0, it flew to 145k ft on 21k Ns. If you have any questions, feel free to PM or reply to the thread. Good luck!!
 
jderimig said:
Hi Dazza,

On your other questions, yes you cannot have your tracker antenna inside a CF airframe. If your nosecone is fiberglass you can put the tracker there. Or you can mount your beeline to the recovery harness and run the antenna wires taped to the hardness. Then you will be able to receive the RF after separation. However if separation fails then you are out of luck.
Click to expand...

Thanks John.
 
Regarding the tracker, you can either go with a fiberglass nose cone for the tracker, or use a fiberglass coupler and a larger than normal fiberglass switch band if they choose to put the tracker there. The weight difference won't be that significant given the relatively small amount of material. Metal tip on the nose cone is fine, as long as you keep the antenna 1/4 wave away from it (about 3" for a 900 MHz unit).

As far as the staging, for something like this which is a pretty expensive project to begin with, you NEED to have electronics that are IMU-driven for off-axis staging protection. Telemega comes to mind. You can do it with some accelerometer-based altimeters (i.e. Raven), and some baro-only altimeters too (i.e. Eggtimer), but they are using inferred data to determine that you're going straight up, they don't measure it directly as an IMU-based solution would, and in a project this major that's a big difference. The proper electronics will cost you a few hundred dollars more, but if it ensures that it's going to work and you're going to get back all of your rocket then it's a pretty good investment.
 
dazza98 said:
RRC 2 Marsa 4 and 54 bee line Have built and flown many L3 rockets but I find using sticky tape is the best to hold on fins. I remember why I stopped using this forum now I ask for advice and get laughed at. shame on you guys.
Click to expand...
You got it wrong mate...no one is laughing at you, least of all me.
My "LOL" was directed at the amusing advice that an L2 do an Estes PS II kit and get some experience.
That guy basically apologized for not reading your signature line, and finding out your were a L2, after he posted his advice.

My suggestion that you give us a little more info about your skill set is reasonable - that is, if you want advice relevant to your experience level, which is quite significant - as we all know now.
Not everyone here knows everyone else.

And I love your humorous "sticky tape to hold on fins" ..........
I needed that. We all did.
Made my day, thanks.
 
Last edited:
MaxQ said:
You got it wrong mate...no one is laughing at you, least of all me.
My "LOL" was directed at the amusing advice that an L2 do an Estes PS II kit and get some experience.
That guy basically apologized for not reading your signature line, and finding out your were a L2, after he posted his advice.

My suggestion that you give us a little more info about your skill set is reasonable - that is, if you want advice relevant to your experience level, which is quite significant - as we all know now.
Not everyone here knows everyone else.

And I love your humorous "sticky tape to hold on fins" ..........
I needed that. We all did.
Made my day, thanks.
Click to expand...

mate sticky tape is the best. cant believe you don't use it.:wink:
 
cerving said:
Regarding the tracker, you can either go with a fiberglass nose cone for the tracker, or use a fiberglass coupler and a larger than normal fiberglass switch band if they choose to put the tracker there. The weight difference won't be that significant given the relatively small amount of material. Metal tip on the nose cone is fine, as long as you keep the antenna 1/4 wave away from it (about 3" for a 900 MHz unit).

As far as the staging, for something like this which is a pretty expensive project to begin with, you NEED to have electronics that are IMU-driven for off-axis staging protection. Telemega comes to mind. You can do it with some accelerometer-based altimeters (i.e. Raven), and some baro-only altimeters too (i.e. Eggtimer), but they are using inferred data to determine that you're going straight up, they don't measure it directly as an IMU-based solution would, and in a project this major that's a big difference. The proper electronics will cost you a few hundred dollars more, but if it ensures that it's going to work and you're going to get back all of your rocket then it's a pretty good investment.
Click to expand...

thanks,
 
dazza98 said:
mate sticky tape is the best. cant believe you don't use it.:wink:
Click to expand...

Finally, someone who understands. I have maintained for years that double-sided tape (my brand is Golfsmith grip tape) is the most important tool I own. Could not build rockets without it. Seriously.

Now, I've never considered it for actually attaching the fins, but there is a role even there. I have submitted an article for the December issue of Sport Rocketry. Preliminary title is "Fins Escape? Use tip-to-tape". Hasn't been accepted yet, though.

Jim
 
Ok , I'll bite....what do you use it for?

I have some for holding batteries in place.
Golfworks is where I get powdered lead for nose weight also.
 
blackjack2564 said:
Ok , I'll bite....what do you use it for?

I have some for holding batteries in place.
Golfworks is where I get powdered lead for nose weight also.
Click to expand...

The last time I answered that question, I said ....
----
I'd guess that about half my double-sided tape consumption is in the two sanding blocks in the pic. The small one just seems superior to me compared to any block where the sandpaper is just held in place on the ends. I use the large flat board for sanding the ends of tubes flat, sanding fins flat or beveled, or whatever. I need devices that let me sand things perfectly flat, and these do that.

I attach sandpaper to body tubes to sand conformal shapes. I attach sandpaper to dowels to sand fillets. Etc., etc., on the sandpaper.

I use a lot of double-sided tape with the drill press to hold things where clamps won't fit. Holding a bulkhead to drill the center hole is one of many examples.

I use double-sided tape with my router, again, where clamps won't work. I have a jig that I use to bevel fins. I attach the fin to the jig with the tape, pass it over the bit, and the job is done. Takes 10 minutes to perfectly bevel 4 G10 fins.
----

I suspect the number of times that I have used double sided tape to do something is in the thousands.

Jim

Sand.jpg
 

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