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Nosecone to Rocket Tether

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Sartori42

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So, why to we link the nosecone to the main rocket with a tether? It seems to me the nosecone might bang up the rocket on the way down. Why not put a streamer on the nosecone and leave the parachute for the main rocket body?

Thanks.

Steven
 

sandman

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So, why to we link the nosecone to the main rocket with a tether? It seems to me the nosecone might bang up the rocket on the way down. Why not put a streamer on the nosecone and leave the parachute for the main rocket body?

Thanks.

Steven
'cause then you got two things to chase.;)
 

DAllen

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Trust us...It is waaay better to have everything tied together. Makes recovery much simpler. There are easy ways to make sure the NC and the BT do not bounce off of each other.

1. Use a long shock cord. The length can be subject to much debate here on TRF but many use the following:

shock cord = 3 x the body tube length

2. Use the correct delay. If your delay is too short or long it will cause the nc to bounce off the body upon ejection.

3. Tie off your streamer/paracute roughly 1/3 the way down the cord from the nose cone. YMMV

If they aren't tied together and for whatever reason come down at different rates because of crumpled chutes or whatever they can land hundreds of yards apart even if the flight only goes say 1500'. That just makes recovery annoying difficult because now you have to keep an eye on 2 objects landing in completely different spots rather than one.

-Dave
 
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spacecadet

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How far apart, you say? How about a quarter a mile, even for an F36? That's a lot of extra miles in a day and a lot of lost flying time. Unless you're really fit.
 

Gillard

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There are some rockets that have the nose cone recover separate from the main body such as Quest's space clipper.
but with two things to watch , you are going to miss one, and a nose cone on a streamer is easy to lose in grass thats only a few inchs tall.

the nose cone should no bang into the body if you make sure the parachute is attached to the shock cord near the nose cone - most people go for about a third way down. however, if the shock cord is to short eg every kit Estes has ever produced, the nose cone can bounce back and hit the Body tube leaving a dent - the Estes dent as its been called.
 

Sartori42

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Thanks for all the replies. As a beginner here, I'm not talking about rockets that go very high. I don't think any of them are supposed to go higher than 700 to 1000 feet. I had planned to tie my MadCow nomex parachute protector (orange) to the nosecone and allow it to drift down while the rocket body came down on the parachute. The orange color should make its location fairly painless while I focused on the rocket itself. However, the overwhelming concensus here is that's a bad idea. No worries, as I have built my first models according to the instructions, so everything is tethered together. I was just trying to think of ways to improved the process.

Cheers.

Steven
 

adrian

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There have actually been kits designed to come down in two pieces, including some in which the nose cone didn't have a streamer, it had rotor blades and spun on the way down like a helicopter.

Another way to prevent the nose from banging into the main body is to extend the shock cord past the nose cone and have the parachute or streamer tied to the end. In other words, instead of the usual arrangement of nose-parachute---body, what you have is parachute--nose----body. Both the heavy parts are then in line rather than next to each other, and it also has the advantage that if the rocket lands in long grass, the parachute or streamer might sit on top of the grass and make the rocket easier to find.
 

Micromeister

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That doesn't seem like a big deal.....

How far apart can they end up?

Steve:
While it's very possible to use dual recovery for your model bodies and Nosecones, and we do. As Sandman mentioned for general flying that can get into a lot of extra recovery time, which cuts down of the number of flights you can make on any given flight day. While that may not seem like a big deal now, as time goes along it can really cramp ones style:)

If you have a model that has a very heavy nose area or very fragile attached tower or other detail using dual recovery is a very good choice.
For your run of the mill sport flying models, it's a lot easier to lengthen the shock cords, Particularly if your building Estes kits. and attaching the chute about 1/3 of the way down the shockcord with a simple butterfly knot. This well ensure the Nose and body do not hit together on the way down or spring back damaging the forward end of the bodytube ie "Estes Dent" caused by those Way to short supplied shockcords.
Hope this helps a little.

ButterFly Knot-sm_4pic tutorial_07-20-05.jpg
 

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Sartori42

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More good info that's appreciated.....

I guess I'll learn about the recovery time comments. I haven't launched a rocket in more than 30 years and this will be a first for my son. However, I don't envision being in a rush to launch as many times as possible. I want to take our time and enjoy every launch. Due to cost considerations (I'm unemployed right now), I want to make as much as I can out of each launch. If my son has to chase one part while I chase the other, I don't see that as a big deal....

We've built 3 rockets so far (winter here is a good time for indoor activities) and we're looking forward to our first launch when the weather cooperates. I built a Interceptor E (not the best model to start with), while my son built an E2X Converter. He was done in an hour, I took 3 weeks. I recently built a Big Daddy, which was MUCH easier. We have two more to build (he a E2X Blue Ninja, and me a Quest Harpoon) and then we're ready to go. All have been built according to instructions with the supplied parts. It isn't until I started reading more here on the internet that I found out many people modify the kits to make up for shortcomings in the design. So, this thread is about me considering what to do in the future. The fact that there a stock term "Estes Dent" tells me that others have an issue I've only imagined.

Thanks again for all the replies. It's nice to have a place to ask questions....

Steven
 

Pippen

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Hey Steven, you're right that there's a lot of modifying going on around these parts. You might want to get a few of those birds in the air and see how they perform and then consider what modifications might work best for what you've built and the field(s) you fly in. It sounds like you've got a nice set to start with!

If you're on a budget, you might want to check out the low budget rocketry ideas in this thread. Art Applewhite's free saucer patterns, rockets made from cardstock and free stuff around the house all make for some fun, creative and cheap launching.
http://www.rocketryforum.com/showthread.php?t=936

We'll be waiting for your launch report, and pictures if you take any!
Lisa
 

n5wd

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...I'm not talking about rockets that go very high. I don't think any of them are supposed to go higher than 700 to 1000 feet.
Under the right conditions, a 750' flight can drift a long, long ways away - we reinforced that fact with one of our TARC teams last weekend. They had a tape failure/forgot to tape the nosecone down, and the nosecone separated on the way up. It wound up about 1/2 mile from the rest of the rocket body/payload bay which was tethered together with some kevlar line.

And though everyone's kinda hinted that it's not good, separating your rocket into two parts does have an advantage when you're trying to achieve a repeatable time of flight, like we're doing with our TARC team's rockets (our kids are trying to carry a single-egg payload in their 3" or 4" rockets, flying to 750 feet in a flight lasting as close to 45 seconds as possible).

Don't be afraid to put in a real long streamer to help keep the smaller parts visible - crepe paper is fireproof, can be stuffed into a very small space, and can be very visible!
 
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Sartori42

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Well, I may try a seperate recovery once to see how it goes. It shouldn't be too difficult as the shock cord doesn't seem to be ever permanently attached to the nosecone. I'll attach the MadCow nomex parachute protector to the nosecone and the parachute to the body and see what happens. If I don't like it, I can always tie the shock cord back to the nosecone. I don't see us launching on windy days, as I gather that makes things *kinda exciting*....

As far as launching on a budget, it seems to me that engines are the most expensive component. I "invested" in the nomex parachute protectors so I don't have to buy Estes wadding. I understand you can use cellulose insulation from Home Depot, but I wasn't so sure about the loose nature of the stuff. I've seen the Sunward baffles, but wonder if the really work as advertised. Anyways, I think if my son and I can launch once in a while, and occasionally add to our rocket fleet, we'll be within the approval range of the "family financial advisor". :)
 

n5wd

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I "invested" in the nomex parachute protectors so I don't have to buy Estes wadding. I understand you can use cellulose insulation from Home Depot, but I wasn't so sure about the loose nature of the stuff.
The cellulose insulation is commonly called "dog barf" since that's what it resembles. Get an opened bale at your local Home Depot or Loews - mine had what appeared to be a handful of stuff missing from the huge bale and I paid half price (about $6 IIRC) for it. We use it at school plus my personal launches, and we've got more than enough to last us for a couple of years! It's fireproofed so it won't burn - just grab a handful of the loose stuff and drop it into your tube. Don't compress it too much - packed too tightly, it might have a problem being blown out by the ejection charge. A couple of inches deep is fine.

I've seen the Sunward baffles, but wonder if the really work as advertised.
Though I haven't used a Sunward baffle - baffles, in general, work just fine. I use a couple - in my P-chuter XTreme and in my 3" TARC-task rocket (it's built with a zipperless design, so a baffle in the top of the booster section works quite well), and love 'em. No wadding or dog barf needed. They're easy to construct from scratch - I've got some pix of my 3" baffle that I'm going to post soon with a quickie "how to". I'll use the same design to retrofit a couple of other rockets I've got, as well.
 
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