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Scratch-built nose cones?

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Scratch-built ogive cones?

  • Stick several balsa sheets and shape a cone on a lathe

  • Balsa, but some other way (please explain)

  • Stick several plastic sheets and shape a cone on a lathe

  • Plastic, but some other way (please explain)

  • Other (Please explain)


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DexterLB

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So far I have used only comersial ogive cones for BT-20 tubes and conical scratch-built paper+ex-foam nose cones for other tubes, because only NC-20 cones are available here, and it's pretty expensive to order nose cones online because they are used in industrial quantities :wave:

But does someone know how to make a scratch-built ogive nose cone? Has someone made such cones?
 

gpoehlein

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How about turning a master that is just a bit smaller than a BNC-20, then vacu-forming all the ogive cones you want. George Gassaway had a section on his web page on building a vac-form using a vacuum cleaner and your home oven, but I don't have a link any more (he was on AOL and that is the last URL I have). George?
 

dave carver

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Many have made their own nosecones due to the unavalibility or odd sized. I have made them from BT20 sized balsa, pine wood 3" x 12" 4:1 for my Conformation rocket(before HPR certification you confirmed) all the way up to an 8" x 24" 3:1 cone made from glued together blue styrofoam disks from 2" thick insulation foam.

A way for you to make your own, do you have a electric drill? Well, take your balsa of proper length and on what will be the shoulder end drill a hole and glue a dowel into it. When dry chuck it into the drill and using rough sandpaper get it close to the right shape then switch to a finer grade sandpaper for finishing. It's easier to shape if you take the edges off and make it an 8 sided block. The more you do the better you'll get at making them.

With all the others that will be posting on this I hope you get a good idea on how to proceed:cyclops:
 

sj_h1

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Many have made their own nosecones due to the unavalibility or odd sized. I have made them from BT20 sized balsa, pine wood 3" x 12" 4:1 for my Conformation rocket(before HPR certification you confirmed) all the way up to an 8" x 24" 3:1 cone made from glued together blue styrofoam disks from 2" thick insulation foam.

A way for you to make your own, do you have a electric drill? Well, take your balsa of proper length and on what will be the shoulder end drill a hole and glue a dowel into it. When dry chuck it into the drill and using rough sandpaper get it close to the right shape then switch to a finer grade sandpaper for finishing. It's easier to shape if you take the edges off and make it an 8 sided block. The more you do the better you'll get at making them.

With all the others that will be posting on this I hope you get a good idea on how to proceed:cyclops:
I have used this method but the real trick is to get it to fit in the tube properly. I have had to fall back to using a coupler glued to the cone to get it right.
 

Micromeister

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So far I have used only comersial ogive cones for BT-20 tubes and conical scratch-built paper+ex-foam nose cones for other tubes, because only NC-20 cones are available here, and it's pretty expensive to order nose cones online because they are used in industrial quantities :wave:

But does someone know how to make a scratch-built ogive nose cone? Has someone made such cones?
Dexter:
Pretty much I Make the majority of my own nosecones, I have the lathes and tools to do so fairly quickly and have lots of "stuff" in the shop that can be turned.

There are several types of "Foam" that can be used SM blue or pink closed cell styrofoam insulation can be easily had in 1" to about 3" thickness which works out pretty well. Can be glued and somewhat epoxied into blocks for turning.
Hi density foams (Signboards) in 15 to 22lb per cu ft. make excellent cones but is pretty expensive if you don't have access to trash/scrap stuff.
Balsa and Basswood blocks aren't all that expensive if you can put a bit of an order together with other things to offset the freight, buying on-line can help with the cost.
Turning from hardwood dowels or scrap blocks can be done but tend to be on the Heavy side.
Hardwood turnings are GREAT for making Molding plugs or for laying up super light weight 1/4oz/SqYd. glass cones and bodys for that matter.

Or as Greg mentioned earlier used with any of a number of Vacuum forming techniques with .010" and .020" Sytrene sheets. recently I've been playing around with attempting to Vacuum form T2, T2+ and T3 Micro Maxx size nose cones this way. I have a 10.5mm Styrene cone that works great in .020" styrene.

Rokitflite, myself and others have been "Casting" Nosecone for a good while now. Making the rubber molds can be expansive and it really takes some time to get good at making Hollow cast cones you should talk to Rokitflite about casting hollow two piece cones, He does a BT-5 size cone that is just about as good as any injection molded cone. It's a little easier to add micro-balloons to lighten up the epoxy-resin for smaller cones 6mm to about BT-60 size. I did a bunch of Glo-in-the-Dark cast resin cones with Zinc Sulfide Phosphor and a batch with Strontium Aluminate a while back that I still use for sport models...did I mention solid cast cones are on the heavy side LOL!!

If your just staring out, I think you'd be most happy turning Sm foam cones. it's messy but sorta fun once you turn one or two. all you really need is a drill or better Drill press, a file, some sanding blocks and a tool rest for support. Its better to have both ends of the turning held but can be done from one end if thats all you have.
 
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Zack Lau

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I buy balsa blocks and turn them on a minature lathe intended for metalworking. For accurate scale models, usually use the documentation on hand to make a full size template.
 

Micromeister

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Depending on the size of the cone needed, I generally use a wood lathe with standard woodturning tools, Percission is gained by the layout and measuring tools employed. I've only rarely needed the precission of my small metal turning lathe which is generally reserved for percission mandrels and other metal turnings.
Even a lathe made of Scrap wood pieces and an old hand drill can produce some very precise work as long as you have decent cutting tools and a tool rest.

Size of the tools or machine needed really depends on your modeling needs, there are some very nice small and mid-sized wood working lathes available that will serve most model rocket flying needs and well set you back less then 150.00 bucks.
Invest more in decent cutting and measuring tools will generally give better results then an overpriced machine you only use once in a blue moon...that's words of experience speaking having several machines laying around that almost never get used;)

Turning Tools-e_upper storage & gages_05-20-04.jpg
 

Trident

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Dexter,

I turned my first nose cones when I was 12. I clamped my Dad's drill onto my Mom's step stool, and used the balsa block on a dowel method to turn them. So you really can successfully use pretty primitive home made lathes!

To size it while on the drill, just use a long enough dowel that 1/2" (25mm) or so is showing between the drill chuck and the base of the balsa block. Put a small piece of body tube onto the dowel when you chuck it into the drill, and you have your gauge for checking to see if the shoulder is the right diameter as you sand it down. Once it is, slide the body tube onto the shoulder, and you can precisely sand down the nose cone to be the same diameter as the body tube.

You do not want to remove a nose cone before completing its sanding! You will have a nearly impossible time getting it back into the chuck, such that it is not wobbling some when spun to speed again.

BT-20 is easy to turn this way, BT-50 not too bad, and anything larger like BT-60 starts getting a little harder, but it is possible.

On the balsa blocks, I would draw the profile on each face, and use this to chop off most of the excess using a razor saw. A rasp is a good tool to take off more, and try to get the cone reasonably close to the rough shape, so you are not having to sand a huge amount of the balsa block. Also, if you try to sand a fast turning square block, watch out for flying pieces. As always, be safe and wear eye protection.
 
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Stymye

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I make my own balsa cones (If I need to).. my lathe is small so the larger cones I make with up to 3 pieces and just glue them together. I like scale missiles so it's good to have a way to make non-commercial cones.. plus lathes are so beneficial to a hobby in rocketry
 

U812

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I made this one by hand for my scratch build. Wasn't hard and came out very even.











There's the basic procedure I used.



Them I cut and adapter.



Glued it to the bottom of the cone and inserted it into the tube and contoured it to fit the BT-60 body tube.





After that I used floor sealer, red putty and primer to get her smooth. Then made a mold out of RTV silicone and produced them out of Alumilite. Worked great.

Steve
 

U812

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Here's the following steps. Believe me I wondered if it could be done and was skeptical. Lathes are best if you have one. I have a large vacuum form machine but the draft on this cone is too deep. It would be best to pull it into a female mold anyway so it fits the tube correctly.



Floor sealer.



Red putty. BTW the floor sealer is polyurethane.



Saned and smoothed. The tail cone was done the same way.





And the final masters before molding.



And here they are on the finished model.

Hope it helps.

Steve
 

dlazarus6660

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A friend use to cut out rings in balsawood using a hole saw, glueing the rings together and then sanding it all down after attaching it to an electric drill and sanding with a belt sander.
The drill rotated one way while the belt sander went the opposite way. If that makes sense, it made quick work of it, almost as fast as a lathe.
 

Handeman

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I glued the pink insulateing foam sheets together into a block. Epoxied a dowel in one end, put it in the drill press and used a file to form the nose cone. A coating of epoxy to smooth out the surface and you're good to go. My nose cone has flown many times and even survived a 80G flight on a Warp 9 load.
 

BrianWolfe

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I glue up poplar blocks and turn them on the lathe a little smaller than desired then vac-form them in .125 ABS plastic. Oh yeah I have been working on a vac machine that can do pulls 12' x 4' x 2'.
 

JPVegh

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Very nice work U812. Great example of a hand made craftsmanship.
 
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