Question about MD rockets

Onebadhawk
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mpitfield said:
Yeah but Nathan has an unfair advantage, he is actually a robot as there is no way a human could finish a rocket that well...just ignore him.
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It's actually not that difficult, just takes a lot of time. Patience you must have, young Jedi.
 
This is why I only worry about doing "50 foot" paint jobs (they look great out on the pad)

26613736165_5f1f8eabf7_c.jpg

26010546133_3dfa480037_z.jpg
 
Dragoon said:
...
So heres the question(s). To all of the seasoned Rocketeers whats a good MD rocket to start with? Also beyond that what would be a good progression to go on as far as 29mm rocket then a 38mm so on and so forth. Any and all help, guidance, advice, and suggestions are welcome.
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Already been mentioned but here's my :2:

Start with an Apogee Aspire or scratch build something like it.
PRO's = Inexpensive to buy and build, won't break the bank to fly, not so bad when you loose it.

Next - Blackhawk 38
Pro's = This kit comes with lots of stuff you're going to need.

With all MD rockets the two key ideas are "keep the fins on" and "recovery". You will need to reinforce the fins, and RDF or GPS electronics are recommended.
 
scsager said:
With all MD rockets the two key ideas are "keep the fins on" and "recovery". You will need to reinforce the fins,
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I'll disagree with that.... plenty of people have been over M2 without reinforcing the fins.
 
DavidMcCann said:
I'll disagree with that.... plenty of people have been over M2 without reinforcing the fins.
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Well OK if you say so... maybe I misspoke, or didn't give enough detail.

My personal experience is - something as simple as "landing on a hard surface" is enough to break off surface mounted fins. I have had this happen so many times I've lost count. No need to break Mach to break a fin.

Also, really fast rockets tend to shred more often. I've seen plenty of those, but never had one myself... yet. :)

Insufficient coupler length and weak fin joints are the usual culprits.
 
mpitfield said:
And so it begins
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They have.... It's not -needed-. Your points about longevity and surviving multiple hard-hitting flights are exceedingly valid. But the statement that he would "need to reinforce" MD's fin's is incorrect. If he's going to pop a few J's, it's really not needed even for multiples.

I certainly don't begrudge anyone doing T2T...nor shake my head at it. I don't think it's a bad thing. You KNOW your fins are never coming off. Thats a bonus. I'm pretty sure mine aren't....not positive. All my comment was toward the blanket statement that "all MD's need reinforcement." That's simply not true..... Now in the realm of "stuff it full of motor and light the end", yea, it's a pretty good idea....
 
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DavidMcCann said:
https://www.flickr.com/photos/31757945@N05/28140776303/sizes/c/

1/3 of a mile or so? Don't worry she's in flying condition, all good to laugh. ;)
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That was epic, hate to admit I couldn't help chuckling either. I was beginning to wonder if an ox had hitched up to it and was dragging it. Hope someone took the opportunity to plant some seeds behind it...

I've actually wondered if there were any way to have the chute automatically release in some way after landing, but it's probably not practical.
 
neil_w said:
I've actually wondered if there were any way to have the chute automatically release in some way after landing, but it's probably not practical.
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someone, somewhere did that or was working on it.... I forget who at the moment...
 
I really appreciate all the feedback and help ill be calling wildman here in the next week or so to pick up a blackhawk 38 while im at AirFest AND maybe JUST maybe convince the girlfriend to buy me the rocket i want the most the Darkstar Extreme .............theres a member of my club that has one and its my personal goal to completely demolish his in a drag race but we shall see its a really expensive rocket ..............either way ill have my first MD to build so that should keep me busy for awhile

Again to everyone i really appreciate all the help and feedback everyone has given me!! :)
 
DavidMcCann said:
They have.... It's not -needed-. Your points about longevity and surviving multiple hard-hitting flights are exceedingly valid. But the statement that he would "need to reinforce" MD's fin's is incorrect. If he's going to pop a few J's, it's really not needed even for multiples.

I certainly don't begrudge anyone doing T2T...nor shake my head at it. I don't think it's a bad thing. You KNOW your fins are never coming off. Thats a bonus. I'm pretty sure mine aren't....not positive. All my comment was toward the blanket statement that "all MD's need reinforcement." That's simply not true..... Now in the realm of "stuff it full of motor and light the end", yea, it's a pretty good idea....
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I agree with that but you have to know your material. Plywood on a cardboard tube is not the best for high mach flight without some "help". I don't care what epoxy is used on the tube/fin fillet, the cardboard will eventually give way.
Sure Mach "oneish" with a small rocket is usually not a problem. A glass rocket with glass fins could withstand a lot with careful surface prep and a good epoxy without T2T but if one were going to extremes above Mach 2 for any length of time,
the rocket with T2T is more likely to survive than one without. Flutter is the enemy here.

I converted an Aerotech HV Arcas to DD by just providing an extra bulkhead and a magnetic switch for the Adept22 altimeter. Flimsy plastic fins. Flies all day to ~1400' on an H128. Really nice as both deployment events are easily seen.
Used an H165 one time and I noticed a "burble" on the ascent when the rear of the rocket shook from side to side uncharacteristically. Uh oh, I thought "flutter". Sure enough when I got it back, one fin was cracked at the base. It was still on the rocket and was an easy fix but not going to fly with anything other than an H128 from now on.

Oh, last fall I had a really lengthy fin furrow job on a 4" cardboard camera rocket. It landed pretty far away and the camera was upright at times and it shows me running and walking from a long distance away to try to catch it. It was heading towards a highway.
I got to it in time and it was still pretty far away from the highway. That's hard to judge though in an open field. Didn't keel over dead from a heart attack so I suspect I passed the stress test. Only thing is I have to fix up the open end of the sustainer tube as it
was mis-shapened by the drag. It was a thin walled cardboard LOC tube. Kurt
 
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Dragoon said:
the rocket i want the most the Darkstar Extreme .............theres a member of my club that has one and its my personal goal to completely demolish his in a drag race but we shall see its a really expensive rocket
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There you go, forget the 75mm MMT that comes with the Extreme Dark Star and just shove a 98mm motor up the airframe and then challenge him to a drag race...talk about sleeper.

Have you seen the Ultimate Dark Star, a pretty big rocket but a lot of fat on her. Having said that the 8" Jumbo Dark Star makes the Ultimate look like a lean MD bird.
 

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