An “easy” way to get clay nose weights to stay in the the nose cone

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Voyhager3

Orange is best color, NAR/TRA L2
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So about 10 minutes ago I was adding nose weight the way I had been doing it. By putting the clay in and ramming it in like packing a musket. But then I made the realization that since clay is malleable I could spin it around and the clay might be able to be forced down into the tip of the cone. So I loaded up the clay and spun in a circle for a few seconds.
The good: It works great
The bad: maybe do this if you are, well, “fragile”. Because falling over is very likely
But I guess you could tie a string to it then do it like that…
But my way is more fun so that’s what I’m going to do
 
2 part foam would seal it in, never to be removed.
Yes it would. The upside to a water activated polyurethane adhesive like Gorilla Glue is it’s availability - some places it’s right at the checkout counter - and ease of use. The OP wanted easy, can’t get much easier than GG and a few drops of water.

Now if you’re building something at a higher level than an A/B/C/D/F (maybe G) powered model rocket 2-part foam has some real advantages.
 
For the record, I'm a fan of BBs (or small split shot fishing weights) and epoxy approach rather than clay. For larger rockets, I usually epoxy in a 1/4 or 5/16" coupler to provide weight, and the ability to screw in more weight, or a small av bay in the nose.

Attached is a somewhat blurred photo of 1/4" coupler in about 1.25 oz of epoxy, in nose of 3in Big Red Max I recently finished.
 

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I sometimes dribble in some 30m epoxy on top of the clay, to provide an adhesive cap. wouldn’t do that for HPR, but for a couple ounces, it works well.
 
I Agree for HPR, Lead shot and epoxy are tried an trued methods for sure. No problems.

For clay on an Estes mini V2, Big Daddy and/or DoorKnob or the like I gently rough up the inside of the nose cone, compact the clay well and add a glue cap.
 
Just lasts night I read someone suggesting putting the nose cone in hot water (not hot enough to melt it, obviously) which would soften/melt the clay so it runs to the tip and casts itself to the shape of the cone, and probably sticks a little better, too.
That was my one great contribution to the hobby. I've since discovered, to my surprise and dismay, that not all plasticine clays soften sufficiently in boiling water. So it doesn't always work, but it's terrific when it does.

That said, I think I have to try swinging a nose cone on a string like a centrifuge, if only to see how much fun it is.
 
2 part foam would seal it in, never to be removed.
I've thought about trying that before, but was afraid of the foam possibly melting the plastic nosecone. So that isn't an issue?

Funny side note is that one of my summer jobs as a teen was at a commercial refrigerator plant (diner cake displays, etc.) and I once stepped in a puddle of spilled chemical expanding injection foam and the rubber sole of my shoe melted!
 
Quick answer: it depends.

Some "plastic" nose cones are made of polystyrene, and epoxy generally adheres to the quite well. Some are polypropylene, which is notoriously hard to make anything stick, but the expanding polyurethane foam just might do it. And if it expands up to the nose cone base so the whole mass is mechanically restrained then adhesion doesn't matter.

And I'm sure there are other materials in use, like the PLA and ABS you're most likely to find in 3D printed parts.

And if foam is desired, there's the question of chemical compatibility between the nose cone material and the foam that Ken brought up. There could easily be materials in which the foam gives better adhesion but also damages the part.

Those are just some of the key questions, those I could think of quickly. And I can't give you the answers to those, let alone give any promise that there are not other key questions.

So, in summary, it depends.
 
If the lead shot and epoxy are down in the tip, do you need to back that up with expandable foam to insure it won't pop loose? Esp. on launch?
I haven't used foam in my nose cones, so I can't answer to that; however, I would say that if you're using lead and epoxy in the nose cone, you should do something to ensure it doesn't come loose (especially on high thrust motors).

In those situations I usually drill holes near the tip in a cross formation (without intersecting), then add metal screws or wood dowels, then add lead/ BBs, then epoxy, then trim off the ends of the screws/ rods/ dowels. You can probably see some of this in High Power build threads.

Edit Add: The bigger the rocket and/or the more weight you're adding, the more you need to ensure the weight doesn't come loose or shift because that may make the rocket unstable as it launches off on a high thrust motor when it may have been deceptively fine on lower thrust motors.
 
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Lead shot and epoxy. Drill half inch hole in base of nose cone. Fill nose cone with peanut foam used for packing.
Tape hole shut.

Mark C
 
I used metal rods crossed in the tip of the NC on an Estes polystyrene part. Mixed some BSI 30-min on a post-it note pad and then poured the lead shot into the mix, continued mixing until all the shot was coated, then scraped the mess off the post-it into the cone. Pushed it down to the tip so everything was filled and leveled out. On that one, I was stuffing the chute up into the NC, so I had pre-prepped a round wooden "float" with a screw eye through it. The float kept the eye oriented upward when I sunk it down into the shot and epoxy. Had a short leader of 1500-lb Kevlar with "perfection knot" loops at each end, one already on the screw eye before gluing it in. Attached the 100-lb Kevlar shock cord to the other end of the leader.
 
If you are going to put 2 part expanding foam into a nose cone, can't you just measure out Part A and Part B separately, then add each, and mix them quick in the NC with a dowel? You'd want to add it in several small batches because of the heating - right?

Asking because some have said it starts to react so fast you may not be able to mix them first, then pour them into the NC.
 
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