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Making sonecone OD a little bigger...

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Justin Horne

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I recently fiberglassed some tubes. Now after putting my nose-cone in, I can see that the OD of the tubes is about 3/16 inch larger than OD of cone? What can I do here? I can really sand that much of the tube down, because then it would be very thin. Any ideas? Thanks.
 

qMaxx

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Get some 1/64" plywood and cut some strips from it. Make the first fairly wide (not knowing the diameter of the nose and the length, I can only guess at how wide), maybe about an inch or so. Epoxy it to the nose at the base, and then keep adding strips, but cutting them more narrow as you increase the diameter. Once you get the correct diameter, sand everything down so you get a smooth curve, rather than the "jaggie" look.

If it's a plastic nose cone, you might be better off using sheet styrene and CA, rather than plywood and epoxy, then give the entire area a layer of fiberglass to hold it all together.

You could also do a combination of the above, and sanding the front of the tube down a little.
 

sandman

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the tubes is about 3/16 inch larger than OD of cone
WOW! That's a lot!!

Try this...it'll look goofy untill you are finished.

Build up the edge of the nose cone with masking tape to just under the OD of the tube.
Do another layer of tape above that but not as big then another until you have a stepped "transition section from the new OD and some what blended into the nose cone. then fill it in with automotive bondo or some other putty that will get hard enough to sand.

You can build up the whole edge of the nose cone with Bondo but the tape makes it easier and a lot less Bondo.

Maybe this "exaderated picture might help explain it.

sandman
 

Hospital_Rocket

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How about treating it like a candle?


Melt a pound of wax and dip the nosecone repeatedly until you have just under the thickness you need. Then cover with a layer of epoxy to form a shell. Pull the original cone out, melt the wax, then using a filled epoxy cement the immer cone to the new shell.

A
 

Justin Horne

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Originally posted by sandman
WOW! That's a lot!!

Try this...it'll look goofy untill you are finished.

Build up the edge of the nose cone with masking tape to just under the OD of the tube.
Do another layer of tape above that but not as big then another until you have a stepped "transition section from the new OD and some what blended into the nose cone. then fill it in with automotive bondo or some other putty that will get hard enough to sand.

You can build up the whole edge of the nose cone with Bondo but the tape makes it easier and a lot less Bondo.

Maybe this "exaderated picture might help explain it.

sandman

Yeah, it is alot.. The cone was small to begin with, before the two layers of glass...:(

I did alot of sanding at the edge today, got it to just ender an 8th. I think i'll use the tape meathod.. The wax meathod sounds promising, but id probably screw it up somewhere.. :)

Thanks!
 

Gus

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Why not just get Sandman to make you a new cone? ;)

Faster, easier, and better.
 

DynaSoar

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Originally posted by Justin Horne
I recently fiberglassed some tubes. Now after putting my nose-cone in, I can see that the OD of the tubes is about 3/16 inch larger than OD of cone? What can I do here? I can really sand that much of the tube down, because then it would be very thin. Any ideas? Thanks.
Glass the nose?
 
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