How to make a nosecone?

[Tommy]

I need to make a nosecone for my increasingly larger rockets, and I can't think of anything. I know about the ping pong ball idea, but that requires a different bottle with a top that tapers more than any I can find. I was thinking about cutting off the top and using and inflating a balloon inside, but I am not sure if the air pressure will push the balloon down.

[Azriel]

Maybe try a part of a plastic easter egg? The balloon will likely be pushed down by air pressure, and even if not, it will need to be frequently replaced

[U.S. Water Rockets1]

Maybe try a part of a plastic easter egg? The balloon will likely be pushed down by air pressure, and even if not, it will need to be frequently replaced

We buy a couple of bags of those plastic eggs because they fit really well and match the curve of the 2 liter pepsi bottles. The biggest size eggs are the ones that we use the most of.

[rockets-in-brighton]

If you want a quick nosecone, use two bottles the same size as your pressure vessel. With one bottle first cut off the base. Then chop off the heavy neck section, leaving a round hole. Fill the hole with a patch cut from a curved section (near the transition between sides and neck) of the second bottle. You can use epoxy or contact adhesive or superglue - it doesn't need to be airtight. Works best with round-shouldered 2 litre bottles, rather than straight shouldered 1 litre. Tape the finished nosecone onto your pressure vessel.

You can also use this nosecone as a mould for a papier mache nosecone, which if made carefully could be lighter if not stronger.

[rockets-in-brighton]

I forgot to say that for starter rockets the exact nosecone shape is not critical, it is more important that it should be a smooth surface without sudden changes in shape. Hemispherical is fine but you can also get away with simple conical noses, which can easily be made from light card.

[Rocket Bob]

If you put a rubber valve stem in a bottle cap ( easy).
Screw it on a bottle.
Pressure-ize to 15 psi ( give or take 5 psi).
Then place a heat gun on the work bench and
heat up the tip of the bottle WHILE you rotate it,
with a bit of practice, you will blow a beautiful
nose cone. Easy, quick. The local tire shop will give
you a valve stem if you ask nicely and tell them of your
project. This is my standard technique.

RB

[Prodigy Rocketry]

The above method is freakishly simple and light. You will get great results with patience. I have looked into other nose cone sources like actual rocketry cones (4' and 4.5") modified for these rockets. Also, you can look into spinners from RC aircraft. These are very light (plastic and carbon fiber type) and can be purchased without the propeller cutouts for these rockets. You can get them in 4.25" diameter also which is about perfect for 2 liter rockets.
http://www.pilot-rc.com/Accessoriesshow.aspx?id=8
http://www.ebay.com/itm/4-25-inch-carbo ... 338772c051