Starting a new build. I'm hoping to get this project done within the next year. Then I need to plan a trip to Black Rock Desert.
The design has been rendered in OpenRocket and I have tried to push the fins as far back as possible to insure the rocket stays stable when supersonic.
I designed this custom Von Karman 5.25:1 nosecone in Blender. In the past, I had experience with 3D programs. I had to learn my way around Blender, so it took awhile, but I'm very happy with the results.
This is what "Lighthouse Von Karman" would look like at Dragon's Teeth On Makalua- Original Image thanks to Eric. The top of the lighthouse was created by the failed print piece
And here is the completed nose cone mold
Next thing to do is to order the materials to kevlar/fiberglass. I may not be able to begin building until January.
Reprinted nosecone, slightly smaller - Allowing for 3 additional wraps of glass.
While there will be a storage bay, I have this mold lined up with the 98mm motor to show how much 3/16 of thickness will be on the glassed nosecone. In the final, the plastic mold (pictured below in black/red/white) will be released from the finished nosecone and will be reusable.
I have spent hours balancing the nosecone mold so the point is true. I then glued it to the storage bay mold. Both the nosecone and storage bay will be a single unit with the lamination covering the entire surface (white, red, black, white). They will not be cut.
3 coats of z-poxy with microballoons (not for weight but for easy sanding and to thicken z-poxy). I sanded first two coats with 220 grit. Final coat I will sand with 400 grit and then add a auto primer.
First coat primer: I was lucky enough to get the first coat of auto primer on before it got cold. More 400 grit sanding since as I am still not happy with smoothness of nose section. Hoping only one more coat of primer and call it a day.
Note: Normally I use Kilz for ease of sanding. The reason I chose auto-primer is the fact that this is a mold. I need it to be tough so I doesn't pull off sections of the mold when I release the finished part from the mold.
Left: Gaps filled in with zpoxy for strength and lots of sanding to smooth. Zpoxy should hopefully hold on when I go to release from the mold. It was a bear to sand back down.
Right: Hopefully the last coat of primer is now applied. Will sand with 400 grit.
I then applied a coat of final gloss white paint and sanded with 400 grit. I then applied second coat. If this were a finished rocket rather than a mold, I would have applied a third and possibly a forth coat before finish sanding and polish.
Nose / airframe mold in final phases. Left: after 2000 grit sanding. Right: After final polishing. Still need to apply mold release wax, then PVA.
The rough area where the nose cone ends is fine, that will be covered with tape to build up the airframe section to match the diameter of the nosecone.
Finally the nose section is nearly complete. The nose tip still needs some smoothing. It also needs a finishing layer of glass. The bumps you see are previous seams from applying 8 total sheets of glass. Here is the nose section stacked on top of the 6XL motor.