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1/3 scale 2 stage WAC Corporal project - What motors should I use?

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rockets

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Hello all, I am looking into doing a dream project:
a 2 stage 1/3 scale WAC Corporal. It will be 4 inches in diameter and 8 feet tall. I will construct it with Blue Tube, fiberglass fins, & more..
But, one big question pops up in my head, what size motors should I fly it on? 38mm, 54mm, or 75mm? I'm more of looking into the 54mm route...
Either way, it's gonna be cool! :)
Thanks,
 

Bat-mite

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Too vague of a question. How high do you want it to go? What will it weigh? How will you recover it?

Your question is like asking, "I like sports. Which one should I play?"
 

rockets

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Too vague of a question. How high do you want it to go? What will it weigh? How will you recover it?

Your question is like asking, "I like sports. Which one should I play?"
He he, LOL! :) Sorry, I want it to get pretty close to 10K. I don't know the weight yet. And recovery is TBD but definitely DD.
Thanks,
 

3stoogesrocketry

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He he, LOL! :) Sorry, I want it to get pretty close to 10K. I don't know the weight yet. And recovery is TBD but definitely DD.
Thanks,
I'm guessing you have the means to cover the 200.00 / 300.00 per flight costs? How do you plan on staging the bird ? How are you planning on coupling the stages together . Who will be flying the rocket for you ?

Eric
 

rockets

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I'm guessing you have the means to cover the 200.00 / 300.00 per flight costs? How do you plan on staging the bird ? How are you planning on coupling the stages together . Who will be flying the rocket for you ?

Eric
Yeah, I have the money or I could have someone make some EX motors for me which is cheaper. I have a Eggtimer rocketry Eggtimer. Either a simple coupler or one of those weird cage looking things. I'm going for the Tripoli Mentoring program test soon so I can fly HPR.
Thanks,
 

BDB

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I think you will need more than a simple Eggtimer to light the sustainer. Look at the Eggtimer Quantum. Cris designed it for staging. You will need at least 2--one for the booster and one for the sustainer. You will also want to use dual deploy (or at least a chute release), if you plan to fly to 10k'.

For motors, get openrocket, build it in the software and run simulations.
 

MClark

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The original Tint Tim booster burned for 0.6 seconds, a motor with a similar burn time would be appropriate.
The sustainer was 47 seconds, not available so a 10 second burn would be closest .
An H or I boost to a J will make it to about 10k.

M
 

rockets

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The original Tint Tim booster burned for 0.6 seconds, a motor with a similar burn time would be appropriate.
The sustainer was 47 seconds, not available so a 10 second burn would be closest .
An H or I boost to a J will make it to about 10k.

M
Do you know how high it would go on a AT M1350 to AT L1000.
Or maybe an AT K2050 to AT K185 would be similar to the real deal.
Thanks,
 

MClark

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The M1350 is as long as the booster.
Would have to use "scale recovery".......burn it in.
 

djs

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Out of curiosity, what is your experience with 2 stagers? Esp high power ones?
 

T-Rex

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I wouldn't be too worried about what motor to use until I was ready to build and fly it. You need a LOT more experience and maturity before a project like this......
 

wadavidson

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My father built a 4" diameter two stage WAC 20 years ago as a test model for the full scale two stage we had built.

This model had two 38mm mounts from what I recall. I believe we flew a I211 or I284 to an H242 for a 3k flight or so. This model wa cardboard and plywood and flew great.

Believe he still has it. Used adept staging altimeter
 

MaxQ

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I wouldn't be too worried about what motor to use until I was ready to build and fly it. You need a LOT more experience and maturity before a project like this......
Well said.
I think a more reasonable sized two stage project is a better approach, I think you would want to master the basics of successful two stage ignition with composite motors first - things can go bad very quickly on a high power two stage flight, and the bigger it is, the more there is to be concerned about.
There are some very good two stage flyers on this Forum...pretty sure they all started with a smaller scale project first.

I'm nowhere near their skill level.....I started with a Cosmodrome Aerobee - Hi......a very cool kit and a very instructive build.
You'll save yourself some time and money going with that - or another good two stage kit....rather than scratch building a larger one as your first foray into it.
With the altitudes you'll get....need to master the dual deployment methods - prior to that.

I believe I recall the 4 inch Wac Corporal two stage project that wadavidson mentioned in his post, - it was a demo/test before they went to the larger one (Damien Ruso and Bill Davidson "Team Wac Corporal/Garden State Tripoli").
High Power Rocketry mentioned that 4 inch Wac project and I believe it was an I to an H flight, as he said.
Before they did their "dream project" (a full size two stage Wac C) - they "did their homework".

After a couple of two stage flights on smaller scale stuff, I built a 4 inch diameter two stage Wac Corporal in the same configuration....38 mm for I to H fights. And only after a couple of smaller projects.
I can tell you a scale looking interstage on a two stage Wac C. is a design challenge.
And that interstage has to be structurally sound. As solid as I made mine - I'm still not satisfied with it.

Wac Corporal Scratchbuilt 4inch.jpg
 
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mrwalsh85

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Heh...

I built my WAC Corporal for my L3. I have flown it on L motors to M motors. I am waiting for Scott to come out with the next load in the big 75mm case.

IMG_7588.jpg

Meanwhile, the thought had crossed my mind to do a tiny tim booster. I wish I had built this thing to handle a booster, but I didn't. So, I am mulling over options to add a booster. I have several friends with very large milling machines, but ultimately, I just need to be able to drill three holes through at least two centering rings, preferably three, exactly in line with the airframe/motor mount so that I know it will boost true and stage cleanly.

I will say that I have no composite staging experience so it's gonna be a while yet before anything happens.... But I have some contacts who are well versed in staging and they have offered their expertise. So we shall see how this goes. I enjoy flying the WAC, however I want to move on up.

We will see what time brings.

Mike
 
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