Big Daddy Lawn Darts... Show of Hands Please.

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K'Tesh

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Ok, you know who you are... Owners of once pristine Lawn Darts... Oops... Big Daddy Rockets that have lawn darted.

Who all has had one whistle in?

[EDIT] The following was posted from post #20:
I wonder if the people who have experienced a BD's Lawn Dart could also mention if they remember if they made the NC tighter, or if it was tight, and they didn't sand it down?
 
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GlennW

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My Big Daddy lawn darted on its final flight, destroying it. I was actually surprised as I thought after all the mishaps it had survived, it would never die. I was wrong. There was a recent thread on here about the problems with the NC on this rocket and how that has contributed to some of the issues that I and others have experienced.

Glenn
 

jrkennedy2

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I've had 3. At first I thought I really bad luck but then noticed many others had similar experiences. Wasn't there a thread a little while back on nosecone mods that helped? On my last one I kept it alive for a while using a little extra bp on top of the ejection clay cap and tape. But, I got stingy and "thunk", tundra dart. (Like a lawn dart but into the hard Colorado prairie dirt)
 

Bat-mite

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If you want a count, a poll would have been easier. But ... I had one, after several successful flights. It waited until a I put a keychain camera on it, destroying both.
 

Nathan

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Here's mine. I have posted this video before.

[video=youtube;hTizGyCO4BI]http://www.youtube.com/watch?v=hTizGyCO4BI[/video]
 
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jpoehlman

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Mine lawn darted on it's first and only flight. Flight right before mine darted as well..... That nice fellow saved me the walk through the mud! I think there where big daddy's that lawn darted at that club launch.... Maybe one success.
 

CZ Brat

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Had one of mine lawn dart. But I can't blame anything or anyone except myself. I forgot to install the ejection charge on my 24/40 motor case. The NC got pushed all the way to the fins.
 

ThirstyBarbarian

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3 times. I also experienced a parawad, and a drift out of the park on the wind. Somehow it kept surviving, until the final lawn dart. I also had problems with the paint and had to sand everything off and repaint it. It's a cool rocket, but mine was really problematic from the beginning to the end.
 

RocketNerd

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I dont get it? whats with all the LD's with this particular rocket model?
 

K'Tesh

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I dont get it? whats with all the LD's with this particular rocket model?
Leading theory is that the way the shoulder is designed, it is capable of venting the ejection charge's gasses before the nosecone pops off and deploys the parachute. Once that happens, gravity takes over, and it comes in ballistic... That is barring, of course, the occasional person using a reloadable motor and forgetting to put in his ejection charge. Another rocket that I've heard that comes in ballistic all to often is the Leviathan, which uses the exact same nosecone.
 

RocketNerd

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The Leviathan (ugly name btw) seems to be a very popular model.
 

JumpJet

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Leading theory is that the way the shoulder is designed, it is capable of venting the ejection charge's gasses before the nosecone pops off
I believe you are going to have to ignore this leading theory. EVERY Pro Series Kit has this exact same type of nose cone including the 4" diameter Mega Der Red Max. My non scientific theory would be modelers for some reason like to have their nose cones not come off easily so they apply tape to the shoulder of the nose cone to increase the friction, or maybe it's just to tight a fit to begin with and they never took the time to sand te shoulder down for a loose enough fit. I for one prefer my nose cones to fall off when the rocket is pointed nose down. I've NEVER had a nose cone come off because of drag separation that some people clam will happen. Maybe you need more friction for high power models that obtain extreme altitudes but for anything Estes related even with uprated motors I don't see the need. Estes has sold Tens of Thousands of our new ARF line which have nose cones with very loose fits. I've actually flown close to two thousand of them with around 500+ two stage flights with our D booster and I never saw one of the loose nose cones come off. So my advice would be to loosen up your nose cone fit.

John Boren
 

K'Tesh

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I believe you are going to have to ignore this leading theory. EVERY Pro Series Kit has this exact same type of nose cone including the 4" diameter Mega Der Red Max. My non scientific theory would be modelers for some reason like to have their nose cones not come off easily so they apply tape to the shoulder of the nose cone to increase the friction, or maybe it's just to tight a fit to begin with and they never took the time to sand te shoulder down for a loose enough fit. I for one prefer my nose cones to fall off when the rocket is pointed nose down. I've NEVER had a nose cone come off because of drag separation that some people clam will happen. Maybe you need more friction for high power models that obtain extreme altitudes but for anything Estes related even with uprated motors I don't see the need. Estes has sold Tens of Thousands of our new ARF line which have nose cones with very loose fits. I've actually flown close to two thousand of them with around 500+ two stage flights with our D booster and I never saw one of the loose nose cones come off. So my advice would be to loosen up your nose cone fit.

John Boren
I wonder if the people who have experienced a BD's Lawn Dart could also mention if they remember if they made the NC tighter, or if it was tight, and they didn't sand it down?

It just seems to me that the BD has a disproportionately large number of lawn darts.
 

Rex R

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it probably doesn't help when, the handbook, and the RSO's all call for being able to 'pick-up' the rocket by the nose...which is fine and dandy if the rocket has a heavy nose.
Rex
 

Charles_McG

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My Big Daddy and Leviathan are both great fliers. And deploy and recover-ers. Hmm. How to (quickly, cheaply and easily) measure nosecone removal force?
 

Bat-mite

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It was two years ago, but my guess is that I over taped mine. I think I taped it at home in the basement, which stays about 60 deg. year-round. Then took it out to a field to launch on a very hot August day. After 30 minutes in the car driving, I think things expanded and tightened up. I should have removed the NC, checked its fit, and removed some tape.

BTW, I have never had my Leviathan fail to deploy.
 

ThirstyBarbarian

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I believe you are going to have to ignore this leading theory. EVERY Pro Series Kit has this exact same type of nose cone including the 4" diameter Mega Der Red Max. My non scientific theory would be modelers for some reason like to have their nose cones not come off easily so they apply tape to the shoulder of the nose cone to increase the friction, or maybe it's just to tight a fit to begin with and they never took the time to sand te shoulder down for a loose enough fit. I for one prefer my nose cones to fall off when the rocket is pointed nose down. I've NEVER had a nose cone come off because of drag separation that some people clam will happen. Maybe you need more friction for high power models that obtain extreme altitudes but for anything Estes related even with uprated motors I don't see the need. Estes has sold Tens of Thousands of our new ARF line which have nose cones with very loose fits. I've actually flown close to two thousand of them with around 500+ two stage flights with our D booster and I never saw one of the loose nose cones come off. So my advice would be to loosen up your nose cone fit.

John Boren
Obviously you have way more experience than any of us, and I'm sure you know very well what you are talking about with regards to Estes kits and how best to set them up for flight. But I don't agree that Estes models NEVER drag separate. I'm pretty sure I had it happen on my Trajector about a month ago. The nose cone very clearly came off right after burnout, and the parachute deployed while the rocket was traveling upward very quickly. Everyone agreed that we saw an ejection charge several seconds later. Of course, it's really hard to say for sure what happened --- maybe the ejection charge went of early and we didn't see the smoke until later. But I had flown the rocket with the nosecone much looser than I usually do, so the next flight I added some tape, and the flight was perfect on the second motor in the same pack as the first. Drag separation is probably not an issue with a fat rocket like the Big Daddy, but on a skinny rocket with high-drag features like the Trajector, it might be.

I had 3 lawn darts with the Big Daddy, and one parawad, and I'm pretty sure I know what happened with all of them except that last fatal one. The parawad was on an early flight, and I think I just did not get enough wadding/dog barf in there. After that, I bought my first nylon chute and nomex blanket. These were both bulkier than the plastic chute, and the nomex was definitely too big. It was too much for the space available, and it jammed in too tight. That's what caused the first lawn dart. The second lawn dart was caused by an E9-6 motor, which was just too little thrust and too long of a delay --- the rocket arced over and hit the ground before the ejection charge went off. The last lawn dart was unexplained. It was a night launch, so we could not really see what was going on with the rocket, but the nosecone definitely did not come off, and it drilled in ballistic. The motor was an E12-4, so plenty of thrust and a short delay, and should have been a good flight. Anyway, I'd chalk most of my Big Daddy crashes up to user errors, but the tight fit of the recovery bay make it a challenge. Even if the sloped nosecone shoulder is not the root cause of failed deployments, cutting it off and replacing it with a bulkhead and eyebolt is not a bad user modification, just for the fact it makes more room to work with for wadding and a more loosely packed chute.
 

samb

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My BD is getting ready for it's "10 Years a BAR" anniversary flight this spring. I hope it doesn't lawndart ! :mad: I think the Big Daddy likes it's nose cone like it likes it's women: LOOSE ! :grin:
 
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Rex R

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I think that should I build another BD, that a small modification from the current stock version is in order. either a) make the body 1" longer or b) install only a 'D' mmt(take it back to original spec.). the 'E' mount takes away too much recovery room.
Rex
 

Oberon

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I know John is the expert but I'm not willing to totally let go of the design flaw theory just yet. I know all the PSII birds have sloped shoulders, so I compared my big daddy side by side with an MDRM and a Ventris. One thing I noticed is that it seems easier to "bind" the nose cone by partially extracting it (just past the start of the slope) and tilting it. Try it - with the Big Daddy it's fairly easy to wedge it in that position, requiring significant force (or sliding it back / straightening it out) to remove. It was more difficult to wedge on the MDRM and Ventris. Maybe just something with the particulars of the ratio of slope to straight to diameter.

I've had success so far (knock on wood) with my Big Daddy by restricting any necessary tape to the very top of the shoulder, and making sure the cone is evenly tight all the way around so it slides out smooth. I also change the tape every flight (sometimes the edges can start to roll over and bind).

As as far as tightness, I usually shoot for tight enough to pick up gently, but possible to shake loose with a little effort.
 

etoyoc

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daughter's had a lawn dart at her 4H launch a few years back. It was repaired and lawn darted. and repaired... and repaired.... It just kept getting shorter.....
 

loopy

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I've had two...first was a week ejection on a D12...other was no ejection event on an F24...
 
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