4 inch diam / 29 mm ??

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Andy Greene

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So whats it take to power a 4 inch diam 29mm airframe that weights 2.25lbs as it sits ???
No - I didnt build it - And yes , I wish it was 38 - and yes , I chopped the fins off closer to the rear of the bt .
34pkxnd.jpg
 
Do you use OpenRocket, if so it will allow you to sim any motor you want. If not/or Thrustcurve.org will allow a quick and dirty (pretty accurate too!) sim. A G64W would probably be a good start.

Thrustcurve.org is also available as an Android app from google play store.

Using Thrustcurve with VERY basic info a AT H165R would get about 1028'.
 
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Guesstimate 4 pounds pad weight x 4.4 x 5 = 88N minimum thrust. So, H128W, H165R in the 29/180 case should work and push it to 800' or so.
 
Thanks guys- This will be a good excuse for me to break out the unused CTI 3g 29 case .
 
I had a Heavy Duty Beauty that flew great on a single 29mm motor. Personally I think 29mm motors have more power than people appreciate.


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I had a Heavy Duty Beauty that flew great on a single 29mm motor. Personally I think 29mm motors have more power than people appreciate.


Sent from my iPad using Rocketry Forum

I'm sure Frank would agree. Those I200s lift his 6lb giant foamies without a hint of struggle.
 
That's NCR Phantom 4000, it should fly fine on G-motors.

I looked on NCR's site but didnt see a nosecone offered separately - who is a good source for a close match or am I just missing something easy - its been a looooong day :facepalm:
Even better, anyone have the proper N/C they want to part with- even one for a Patriot would be fine .
 
Measure the airframe if the ID is 3.9", the Loc, PML, Giant Leap Rocketry, most 4" high power rocketry nose cones will work.
 
My LOC IV was an early one with a 29mm mmt. I built it early in my BARdom with a AT motor mount assembly, so it's limited to 29/40-120 case motors or single use motors. It's always flown well on F50's, G40's and G80FWL's. It's also great on G64's and F52's. I have three NCR 4" kits. All fly well on any appropriate sized 29mm motor I wanna stuff in the pipe. With the advent of the JL CR, I might start to go bigger on the 29mm power scale.
 
I looked on NCR's site but didnt see a nosecone offered separately - who is a good source for a close match or am I just missing something easy - its been a looooong day :facepalm:
Even better, anyone have the proper N/C they want to part with- even one for a Patriot would be fine .

Unless something changed since I looked last, the new NCR doesn't offer 4" kits.
 
I loved the H97 for my Archer, and the G75 for my Patriot. Slowish liftoffs and lots of smoke. I gotta do that again...
 
My old NCR Archer comes in a tad under 35oz w/ no motor. I regularly fly it on F50's and used to fly it on G40's w/out problem. I mostly feed it G64's now and it leaps off the pad in a pretty good hurry.
 
My old NCR Archer comes in a tad under 35oz w/ no motor. I regularly fly it on F50's and used to fly it on G40's w/out problem. I mostly feed it G64's now and it leaps off the pad in a pretty good hurry.

WOW! Good job building. My Archer (4" version) weighs in at 53 oz...
 
Mine might be a couple ounces heavier now with the occasional fin re-glue or re-enforcement, but it's probably still close to 35 or 36. It'll hit right around 400' or so on an F50, good for a smaller field w/out having to use the CR.
 
Get one of those CTI I224 or Aerotech I205W. Should punt it off the rail.
You could always get a heat gun an heat the epoxy up until it fails then replace centering rings with 38mm. I guess someone out east was trying to keep a rocket low for an FAA waiver. Maybe a northeastern dude or Gal built it??
 
I'm sure Frank would agree. Those I200s lift his 6lb giant foamies without a hint of struggle.
They are 11,400 ft-20,000ft capable in staged MD rockets. It doesn't take a lot of cash or a big massive L motor to go Mach plus and break flight levels on a good day.
 
2.25 lb? 3 or 4 grain H will give you a decent ride.

Heaviest I've flown on a 29mm was my 6.8lb Phoenix-- CTI 6XL 29mm white. I-243? Is that right (no worries; someone'll correct me if it ain't)? puts that up in the high 1400's or so...


Later!

--Coop
 
5' 7" tall 4" scratch build - 66 oz on G76 reload :) (700FT)

[video=youtube;YKWy6G59SmA]https://www.youtube.com/watch?v=YKWy6G59SmA[/video]
 
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