Need help with MPR 2 stage with electronics

OK, so I just got a Dynastar Aerodactyl TS for Christmas. I really like it, and it looks to be a really fun build! But, I want to modify it so that it can fly motors lit by electronics.
The booster that comes with the kit is a little small for this, so I decided that the booster would be my LOC Graduator, and the sustainter would be the Aerodactyl. Before I start the build, I have a couple of questions.
Do I need a special electronics bay for the booster/sustainer?
Do I need to do anything special with the MMT in the sustainer?
Is there anything else I should know before building the rocket?





Thanks,

rockets said:

OK, so I just got a Dynastar Aerodactyl TS for Christmas. I really like it, and it looks to be a really fun build! But, I want to modify it so that it can fly motors lit by electronics.
The booster that comes with the kit is a little small for this, so I decided that the booster would be my LOC Graduator, and the sustainter would be the Aerodactyl. Before I start the build, I have a couple of questions.

1.Do I need a special electronics bay for the booster/sustainer?

2.Do I need to do anything special with the MMT in the sustainer?

3.Is there anything else I should know before building the rocket?

Thanks,

Click to expand...

1.Yes, it's called an Interstage coupler or we call the I/S for short.

2.Just some type of motor retention.

3. Yes...this list is so long, it shows you need a mentor to help you.

This kit [I read the instructions..have you?] is built with balsa fins to keep it light weight & use BP motors. By the time you add electronics and batteries and tracking [for both stages] you will need to lift the stack with an AP motor, especially since you wish to use LOC Graduator for booster.
Then you will need to change balsa to plywood on sustainer to safely handle the added thrust & weight. ON & on it goes like domino's. Change one thing and many others must follow.

It looks like a fun build 'as is' and might I suggest building it as such, just to get your feet wet with 2-stager's

You seem like a good kid with a desire for many things rocketry related and I don't want to stop you from your journey. At the same time I don't want you to get in over your head either.

2 stagers are not twice as complex as single stage flier's, more like 10X difficulty. Think about it...if you really decide your ready for such a complex venture, then forge ahead, but PLEASE find a good mentor to help you get there.

The very simplest way to accomplish what you want [way I see it] would be to use a tiny timing stager like Perfectflite to light sustainer. That would get your feet wet. BUT then how are you going to be sure it's vertical before lighting it? Many clubs require some sort of safety check, such as " must be X altitude" or "must be less than 20% off vertical" or must be "at specified velocity X" before ignition.

These things will require more than a simple timer can do. Much thought & design.
I would think designing or building a kit made for this would be a safer- better route to follow.

Have fun & good luck with whatever you decide. Keep reaching for the stars....you'll get there.:smile:

...........is this what you got...?
Nice looking rocket.
Appears to be 29mm black powder motor two stager with gap staging.
https://www.erockets.biz/dynastar-flying-model-rocket-kit-rising-aerodactyl-dyn-5041/

Interesting kit - this was by necessity - due to the BP motors intended for this large 2.6 " dia. rocket - designed to be lightweight, with thin wall airframe, and thru the wall balsa fins.
If you go composites you'll need to rethink the structural aspect and resultant weight gain.

When we designed the AeroDactyl TS, we specifically did everything possible to keep the weight low. But we wanted to make it as big as possible. The result is a model built around thin-walled tubes and other lightweight components. It is big, and when you fly it, you will be impressed. It takes off fast enough to be safe, but slow enough that it produces a thick and billowy amount of smoke. It is like the rocket is clawing its way into the sky. That is why the decals show claw marks on the fins. This beast is carving a path to incredible heights. In fact, we recommend the Chute Release*in the top stage because it goes so high.

The stock kit apparently is not dual deploy, hence the chute release recommendation. So recovery with the higher altitude of a two stager is something to consider.

I'll add to Jim's advice:
1.Do I need a special electronics bay for the booster/sustainer?
Yes, it's called an Interstage coupler or we call the I/S for short.
...sized for your electronic timer or flight computer and battery of course

2.Do I need to do anything special with the MMT in the sustainer?
Just some type of motor retention.
...and a reliable ignitor that will fire and ignite the sustainer with the above, and if not using the BP motors, keep in mind some composites are easier to light than others.

3.Is there anything else I should know before building the rocket?
Yes...this list is so long, it shows you need a mentor to help you.
..well said. The standard set up with gap staging BP motors would be terrific fun with this one...easier to do w/o any mods to the kit.
Looks pretty cool - think I'll get one to add to my Quest Navaho... another old reliable two stager that uses vented gap staging.
Great way to get into two stagers.

Thanks Jim for the helpful pointers!
Will do.




Thanks,

Are there any reliable sources like a website that I can find all the info I need to build & fly a 2 stage rocket?






Thanks,

rockets said:

Are there any reliable sources like a website that I can find all the info I need to build & fly a 2 stage rocket?Thanks,

Click to expand...

All the info...?
There are probably as many ways to go about building and flying two stage projects as there are two stage rockets and motors that go in them.

There are several high performance threads on the subject right here on TRF.

There used to be a "basics of two staging" on the two former rocket forums that shall go unnamed (LOL) but for starters:
https://www.apogeerockets.com/Tech/How_2-Stage_Rockets_Work
https://www.apogeerockets.com/Electronics-Payloads/Staging/PerfectFlite-MiniTimer4-Staging-Timer

Any two stage fliers/mentors in your club?

MaxQ said:

All the info...?
There are probably as many ways to go about building and flying two stage projects as there are two stage rockets and motors that go in them.

There are several high performance threads on the subject right here on TRF.

There used to be a "basics of two staging" on the two former rocket forums that shall go unnamed (LOL) but for starters:
https://www.apogeerockets.com/Tech/How_2-Stage_Rockets_Work
https://www.apogeerockets.com/Electronics-Payloads/Staging/PerfectFlite-MiniTimer4-Staging-Timer

Any two stage fliers/mentors in your club?

Click to expand...

I know of at least 1 flier that is into 2 stage rocketry that's in our club.


Thanks,

I opted out of the "MPR electronic ignition" idea.
I'm building the Aerodactyl like it's supposed to be built.
I'll wait a few more years until I try a HPR 2 stage.



Thanks,

rockets said:

I opted out of the "MPR electronic ignition" idea. I'm building the Aerodactyl like it's supposed to be built.I'll wait a few more years until I try a HPR 2 stage.Thanks,

Click to expand...

I bought one...will build it box stock. Looks like fun.