Nosecone weights
 

:D I'm currently working on another "Madcow" rocket - Seawolf - and the kit is requiring about 1 1/4 pound of lead shot for balancing. To do this, they are asking that I also drill screws into the NC to hold the shot after the epoxy is poured in.

My question is this: After the shot is poured in, what is the best and preferred way to get the epoxy down into the tip of the NC where the shot will be? The length of the NC is about 12" from end to end and is 4" in diameter.

This is the first time I've worked on a rocket that needed that much weight in the NC for balancing. It's also the first time I've worked on a NC that large. I'm just getting into larger rockets that are higher powered and I've found the learning curve to be a little steep at times... ANY AND ALL SUGGESTIONS AND HELP IS GREATLY APPRECIATED AND WELCOMED.

I would do it a different way all together, here's what I do - Before you put anything in the cone, drill a hole through it near the tip, through one side and out the other. Then insert a piece of wood dowel through the hole, with some excess hanging out both sides. Then mix your shot with the epoxy and pour it in from the back. Use dowel to poke at it to make sure it's all in the tip and fairly even. After its all set, trim/sand the protruding dowel ends smooth to the contour of the cone. I've done this on many cones, it's always worked well.

Here's a picture of a recent cone mod to give you an idea.

Another thing to think about. Epoxy can get quite hot as it cures. I place the cone in a plastic bag and then in a bucket of water (stood up, tip down) to act as a cooling pot.

Grim

Guys,

Have y'all considered putting the nose weight farther aft in the cone, away from the tip? In the past, I've added weight, putting it in the tip. Bit an HPR flier out of Austin suggested moving it away from the tip. His point was that having the weight at the tip makes the cone ballistic. If it separates - and that does happen - it will come in ballistic and be potentially very dangerous.

If the weight is nearer the aft end, a separated cone will tend to tumble in, dropping much more slowly, and presenting a lot less danger.

Plus, if you set it up right, with the weight nearer the aft end, you can make it accessible thereby making it adjustable. With heavier motors, you can easily add extra noseweight; with lighter ones, you can take some out.

BTW, I've put up a webpage which depicts several schemes for adding nose weight here: http://www.doug79.com/noseweight/

I do understand that moving the weight aft dictates that more weight be used to get the same stabilizing effect, but, at least in my case, I'm not too concerned about the loss in performance.

It's just a idea for thought - I'm not trying to get in an argument :)

Doug

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Absolutely true, but the penalties are prettoy big. The cone pictured above is one of four for the Wildman Jart. We built two of the four as lit night rockets, this meant the weight had to go in the cone shoulder. The difference between the two configurations was five ounces - that's quite a bit for a small shift, and a smallish rocket.

Nosecone weights
 

I'd like to thank everyone for their input and ideas!!!

I ended up trying something a little different. The first thing I tried was mixxing the lead shot with epoxy and pouring it in from the aft. I used a longer cure epoxy so I wouldn't be rushed. I found it virtually impossible to get the epoxy/lead mix into the cone. :mad: After that, I poured the shot into the cone and poured an even longer cure epoxy in on top of it. In order to do all this, I had to cut the attachment point off the rear of the cone and drill a very large hole, (5/8"), in the end......The 30 minute epoxy was more viscous and easily drained down through the lead shot. :) I've locked this all in place by drilling a small hole in the tip and inserting a 1.5" screw into it.

The exothermic reaction of the epoxy was not a problem and the heating didn't affect my NC in any way.

Now I'm left laughing at the whole mess :chuckle: and thinking of the lessons I've just learned. Thank God there are people out there in "internet-land" that understand what great resourses they are to fellow rocketeers.

LESS viscous...When something is 'thicker,' it is more viscous; if it pours more easily, then it is less viscous.
Just thought you ought to know!

Glad it worked out for you!

Allen

Thanks for the note. I knew what I meant!!! :cool:

I knew what you meant too, pay no mind. There are a few here who really get a kick out of ball-busting for things like that. :rolleyes: