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  #11  
Old 01-06-2019, 01:49 PM
Les Les is offline
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Quote:
Originally Posted by LeeR
Les,

I think you might want to hollow the nose cone. It would allow gases to get passed the end of the motor tube and ďwrap back aroundĒ to get to the ducts you have to cut, assuming you are committed to ducting the ejection gases.

The other option is to not use motor ejection. This means no complicated cuts for ducting, greater strength in the structure, and more reliable timing of ejection by using electronics to blow the chute out. You are going to need a very robust joint at each junction of ducting tube to the upper and lower body tubes.



That was actually my next question/issue. The pods are about 1.22 diameter x 36 long. For all 3 pods that is 126 cubic inches. The Passenger pod is about 2.25 diameter x 17.87 for an additional 71 cubic inches. Total is about 200 cubic inches. For now I have excluded the motor pod (not a lot of spare space in there) and any detrimental effects of static pressure passing through the ports. For even just 12psi that will require slightly over 1.2grams of BP. I believe this is more that what is normally provided in a commercial motor (I normally use CTI)....

One option would be to block off 1 or 2 of the tubes. If only one has ducting than that reduces that volume to 42(ish) cubic inches. Adding back in the passenger pod of 71 and we are at 113 which reduces the ejection charge to 0.7grams.

BUT - for the pod connection I can lengthen the cutout but I can't make it wider - there are still two circular tubes meeting tangentially. Do I now risk blowing up the motor compartment with having only one vent to get the pressure up to the passenger compartment?????

I built the Hawks Hobby upscale and it added some balsa pieces along the tube interfaces to strengthen the bond, but it is only about a 1.4 upscale, not a 2.25

Are there any other beta testers out there? What did you do??? Did you stay with ducted tubes or go to electronic deployment?
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  #12  
Old 01-06-2019, 01:52 PM
Jerry Irvine's Avatar
Jerry Irvine Jerry Irvine is offline
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In the final kit we would likely only make one tube ejection active due to common ejection masses similar to the motors we had certified in the 80's and 90's. The tubes are more than double the thickness of Estes so can't blow up even with 1 ejection active.

http://v-serv.com/usr/NAR-TRA-93.2.htm
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  #13  
Old 01-06-2019, 08:23 PM
Les Les is offline
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Jerry - how have others built and flown this kit?
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  #14  
Old 01-06-2019, 11:00 PM
L3Excalibur L3Excalibur is offline
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[QUOTE=Here is my scratch-built 2.3X collection of parts. Six nose cones done, three to go.
I thru this picture together last year.[/QUOTE]

Lee, and I say this with utmost respect, YOUR WORK AREA IS TOO **** CLEAN!!

Obviously the sign of a totally deranged mind.
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  #15  
Old 01-06-2019, 11:41 PM
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ghrocketman ghrocketman is offline
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Gotta agree with Buzz here...that work area is far too clean and free of clutter.
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Last edited by ghrocketman : 01-07-2019 at 09:45 PM.
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  #16  
Old 01-07-2019, 10:45 AM
jetlag jetlag is offline
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Quote:
Originally Posted by Jerry Irvine
I like this thread and the honest criticism. The kit is in fact in stock for immediate shipment. I don't recall him posting what he paid or how long he waited. ALL comments of this thread's nature are adopted into instructions we create. The whole idea as the poster stated is to have a Trident-ish kit using stock parts. Sport scale if you wish.

Thanks!

Just Jerry

6" and 12" is back!


Jerry,
I don't see it on your site...
Allen
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  #17  
Old 01-07-2019, 09:30 PM
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LeeR LeeR is offline
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Quote:
Originally Posted by L3Excalibur
Lee, and I say this with utmost respect, YOUR WORK AREA IS TOO **** CLEAN!!

Obviously the sign of a totally deranged mind.


Buzz, (and ghrocketman) itís a really awful condition I have managed to live with all my life. And my wife would wholeheartedly agree with you. She used to have a sign on her desk at work that said ďA Clean Desk Is The Sign Of A Sick MindĒ.

In all honesty, though, that is just a big assembly table, and often completely bare. The blue technicianís bench barely visible in this picture is not empty, but it is highly organized with tool holders, storage containers for glue bottles and other often-used items, plus bins for parts.
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  #18  
Old 01-07-2019, 09:44 PM
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ghrocketman ghrocketman is offline
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I'm a fan of the "pile" organization method.
A pile for everything and everything in it's PILE.
My ex-wife is a neat/clean FREAK.
One of the multitude of reasons for the divorce... lol.

I joke that I got a watch (Rolex) for my wife and it was the best TRADE I ever made.
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When in doubt, WHACK the GAS and DITCH the brake !!!
No Harm=NO Foul advocate

If you are NOT FLYING LOW in the left lane, you need to GET THE #$&@ OUT of it !

Yes, there is such a thing as NORMAL
, if you have to ask, you probably aren't
!
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  #19  
Old 01-07-2019, 10:40 PM
Les Les is offline
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Well, I hope everyone is happy with my messy workspace...

Something else I plan to change. There are 3 pod tubes, each 12" long for a total of 36". If I use the 2.25x scale they should be 40.5" long. I have a spare 29mm motor tube. So I am going to use the supplied tube and cut it into 3 sections of 4" each. Adding these to the supplied tubes will give me a total of 40" - close enough.

I also am concerned about fitting this thing into my car, so I would like to be able to separate it - only adds to the challenge of ducting the ejection charge.
Along with the replacement cones, I got a 34" long section of coupler tube from eRockets which I cut into 3 pieces. The plan will be to glue one end in and be able to slide the other end over and secure the tube to the coupler (probably with screws)
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  #20  
Old 01-08-2019, 12:37 AM
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LeeR LeeR is offline
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Les,

Good plan using the long couplers to make your Trident able to break into two sections.

I also used 29mm motor tubes for the duct tubes. While they are heavy walled, I may use full length coupler tubing to add some extra strength.

Iím hoping one of these days Iíll get it built. I started mine a very long time ago ... back in the 90s!
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Projects: Super Sky Hook, Estes Saturn V, Astron Farside-X
Stuck In the Paint Shop: Estes Saturn 1B
Completed!: Painted Prowler! (ditched the pink tube wrap ...)
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