Metal-tipped nose question

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icyclops

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They won't care. The lawyers, and everybody else but you evidently, are sensible enough to know the nosecone tip plays zero part in the scenario you presented.

I also find it really, really weird that you're being such a safety honk aboit materials, yet in another thread, you're relentlessly arguing on the merits of mercury switches for deployment. Further showcasing a poor understanding of physics, safety and common sense.
Hey, I asked a simple question in that other thread if people still used flash bulbs to ignite ejection charges....I asked, I don’t think I said hey everyone, lets go back to the 60s/70s and do it all over again to promote using them. So you can put all the metal you want in HP rockets....go ahead....safety is simply safety and your attitude to justify anything is amazing no doubt. Oh and thanks for the physics lesson...wow.

You obviously don’t know personal injury lawyers :)

Honk Honk.....
 
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Antares JS

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The separate metal nosecone tip gives you a number of options.

For Head End Dual Deploy and smaller rockets, I like to replace the screw with an eye bolt to use as an attach point. This also aids in tightening the bolt - take an appropriate length of PVC pipe - maybe 1" or 1/2" diameter (or sized to your nosecone diameter/eyebolt size) and cut a slot on the end that the eye of the eye-bolt fits into and you have the perfect tool to tighten your bolt to the metal tip. I do not usually epoxy the tip to the bolt in these cases, but I do use blue Loctite.

Here is the one I use on my 5" WM Goblin:

View attachment 452460

For normal DD rockets where the nosecone is big enough that I want to use it as an AV bay (tracker, etc), I replace the screw/bolt and use a long piece of all-thread that goes through the NC AV Bay and use a threaded eye-nut to hold everything together. I use metal screws/PEM nuts to hold the AV Bay in place (just like holding the AV Bay to a payload bay) and the sheer pins go in the AV bay coupler. The AV bay is built out internally as normal. Here is the nosecone to my 4" Darkstar. I flew it 3 times this weekend at MDRA and used a Marco Polo in the nosecone all three times. One of the flights on a K400 landed way out by the highway and the Marco Polo worked perfectly to guide me in from the road.

For these setups, I use red Loctite on the threads of the metal tip. That way I can get them apart again if I really have to.

I plan to be at Red Glare - stop by and I can show you some of these setups.

View attachment 452461

View attachment 452462

View attachment 452464
That's a neat setup, what I'm planning to do now is similar except that the coupler will not be detachable. I'm going to make a sled to attach the tracker to and slide it onto the threaded rod, have a nut above the sled to prevent it from moving, and maybe a couple of stops on the inside of the coupler, if just doing the nuts up tightly isn't enough to keep it from rotating

I take it then that there are no signal issues with the metal rod being right next to your Marco Polo tracker? Again, RF stuff is mostly voodoo to me.
 

mtnmanak

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That's a neat setup, what I'm planning to do now is similar except that the coupler will not be detachable. I'm going to make a sled to attach the tracker to and slide it onto the threaded rod, have a nut above the sled to prevent it from moving, and maybe a couple of stops on the inside of the coupler, if just doing the nuts up tightly isn't enough to keep it from rotating

I take it then that there are no signal issues with the metal rod being right next to your Marco Polo tracker? Again, RF stuff is mostly voodoo to me.
Sounds about right for a NC ebay sled - for something like the Marco Polo. For those rockets, I do a really simple sled. Here is a photo of the sled from the NC pictured in the other post. It is just a scrap pieces of G10 I JB welded to some aluminum tubing. Easy day. More than enough for a Marco Polo. For more complex tracker setups (I also have Eggtimer and Missile Works tracker systems), I do use a better sled design, but I save that for rockets that have a high probably of going far, far away.

Note in this photo, I don't have any nuts holding the sled in place. I use this sled in multiple NCs, so I made it fairly short and secure it in place with nuts each time I move it. Works great and is quick and simple.

PXL_20210302_151749260.jpg


The Marco Polo system works for about 90% of the launches I go to. That is mostly MDRA in the winter and METRA in the summer. For those fields, I am rarely launching anything that isn't going to land in some roughly visible area. It may be far away, but I have yet to have a rocket at those fields land somewhere that I at least didn't have a general clue about the touchdown spot. The MP is excellent within a quarter mile or so and does not seem to be affected by the metal in the nosecones, although, the final resting orientation of the antenna can reduce its range. But, again, at METRA and MDRA, that is not an issue because I have always been able to get fairly close before I needed the MP to guide me in the last 300-500 yards.

If you are going to fly someplace really big (Kansas, Utah, Nevada, etc) and high or someplace with a more complex landing arrangement (hills, trees, etc), the MP may not be adequate. If you mostly launch at MDRA, it should work great.

One more note about the MP transmitter - In a pinch, I have just taped it to the inside of the NC, usually to the center all-thread. Worked perfectly and was fine at the other end. The transmitter is small and tough - it is designed to be strapped to a dog collar. If you don't want to build a sled or the NC is small, you can just tape in there somewhere and it will be fine. For the little transmitter, the manufacturer says you can just clip it to the attach point for the parachute on your shock cord. Either way, it is not a delicate piece of kit - you can basically throw it in your rocket on a tether and it will work.
 

Antares JS

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Sounds about right for a NC ebay sled - for something like the Marco Polo. For those rockets, I do a really simple sled. Here is a photo of the sled from the NC pictured in the other post. It is just a scrap pieces of G10 I JB welded to some aluminum tubing. Easy day. More than enough for a Marco Polo. For more complex tracker setups (I also have Eggtimer and Missile Works tracker systems), I do use a better sled design, but I save that for rockets that have a high probably of going far, far away.

Note in this photo, I don't have any nuts holding the sled in place. I use this sled in multiple NCs, so I made it fairly short and secure it in place with nuts each time I move it. Works great and is quick and simple.

View attachment 453206

The Marco Polo system works for about 90% of the launches I go to. That is mostly MDRA in the winter and METRA in the summer. For those fields, I am rarely launching anything that isn't going to land in some roughly visible area. It may be far away, but I have yet to have a rocket at those fields land somewhere that I at least didn't have a general clue about the touchdown spot. The MP is excellent within a quarter mile or so and does not seem to be affected by the metal in the nosecones, although, the final resting orientation of the antenna can reduce its range. But, again, at METRA and MDRA, that is not an issue because I have always been able to get fairly close before I needed the MP to guide me in the last 300-500 yards.

If you are going to fly someplace really big (Kansas, Utah, Nevada, etc) and high or someplace with a more complex landing arrangement (hills, trees, etc), the MP may not be adequate. If you mostly launch at MDRA, it should work great.
Thanks, I really appreciate the advice. I was indeed going to just go with the Marco Polo as I mostly fly at MDRA. I started thinking about trackers when my level 3 design showed hitting 7000-8000 feet and me planning main deployment at 1000 feet for a big parachute, but GPS still seemed like overkill. I'd like to try out the Marco Polo in a rocket I don't expect to go beyond visual range before relying on it to lead me to a rocket I lost sight of though, which is why I'm putting one in this project.
 

Steve Shannon

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I’m not in favor of metal tips on nosecones for one reason. Before I get to that reason let’s recap what metal nosecones don’t do:
1. They don’t make rockets more dangerous.

The reason I’m against metal tips is because of the visceral reaction that inexperienced people and non-rocketeers have. They see a metal tip and they immediately imagine people being skewered.

But the reality is that a rocket, even a small rocket with a plastic nosecone is perfectly capable of fatally wounding a person. In fact, the only fatality in our hobby which involved a rocket striking a person was exactly that, a model rocket with a plastic nosecone that struck a person exactly wrong.

Those rockets which we build with metal tips are typically used for high altitude and very high velocity flights. They are almost never the flights which come down ballistically behind the flight lines. Those are almost always the model rockets and part of the problem is the lack of attention people pay to model rockets due to their lightweight construction. At least with an all metal rocket people really pay attention.
 

mtnmanak

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Thanks, I really appreciate the advice. I was indeed going to just go with the Marco Polo as I mostly fly at MDRA. I started thinking about trackers when my level 3 design showed hitting 7000-8000 feet and me planning main deployment at 1000 feet for a big parachute, but GPS still seemed like overkill. I'd like to try out the Marco Polo in a rocket I don't expect to go beyond visual range before relying on it to lead me to a rocket I lost sight of though, which is why I'm putting one in this project.
For mounting the transmitter to the sled, when I first bought the MP, I bought one of the mounting kits with a slick little sled that the transmitter clips onto. It works great, but it is overkill. Ever since then, instead of buying the clip on mount for every sled/config I want to try, I just velcro the transmitter to the sled. Or, for NC's with no sled, I took a small piece of G10 (like 1" x 2"), JB welded a small piece of aluminum tube to the back and a piece of velcro on the other side. I velcro the mini transmitter to it and slide it onto an all-thread and let it slide freely in there. Has worked just fine as well. Worst case scenario is the transmitter comes off and bounces around in your NC. You would never want that to happen with an Eggtimer or MW transmitter, but the MP transmitters are tough - I have every confidence they would be just fine if that happened.
 
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mtnmanak

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I'd like to try out the Marco Polo in a rocket I don't expect to go beyond visual range before relying on it to lead me to a rocket I lost sight of though, which is why I'm putting one in this project.
When I first got the MP, I had my kids go around the neighborhood and hide the transmitters and then I would go out and try to find them. It was a fun game! :)

Only time I had interference was when my son was able to slip the small transmitter in the ground at the base of a fire hydrant. When I was on the other side of the fire hydrant, the tracker still picked up the signal (the strength of it), but couldn't determine direction. When I moved past the hydrant, it picked up the direction again.

So, as long as you don't plan to launch any fire hydrants, you should be good ;)
 

icyclops

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Good luck in all your launches and may the Rocket Gods be with you.
 
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cbwho

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Unless that club is MDRA, I'm good. And I would really rather NOT paint it since this rocket is a scale model of a rocket that did have a metal tip.
It's rather easy to paint balsa with silver paint... 🤔

Violations of land owner's rules is idiotic at best and dishonorable.😾
 

Antares JS

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It's rather easy to paint balsa with silver paint... 🤔

Violations of land owner's rules is idiotic at best and dishonorable.😾
The club that has that rule is not MDRA, so I'm good. Also, it's a high power rocket and balsa would not be suitable.
 

cbwho

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The club that has that rule is not MDRA, so I'm good. Also, it's a high power rocket and balsa would not be suitable.
Ok instead of balsa, carbon fiber. If RocketLab can use carbon fiber, surely there is a way.

(This is in reference to that other club.)
 

Antares JS

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Final result: I ended up not epoxying the nose on, instead attaching a threaded rod to the base with threadlocker, drilling an offset hole for the recovery harness anchor, and attaching a stepped bulkhead plate to the bottom of the nose, fastening it with the threaded rod, a lock washer, and a wing nut. Again, I intend to use the nose as a tracker bay once I get a tracker.
 

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