FG Nose Cone Molding

I'm going to start molding FG nose cones for 2.6" rockets soon, so I thought I'de mention it here.
I found a "Mold Maker" at the craft store the I got the Fimo and sculpey clay at, and will attempt to press the dome shaped cone that is actually the cap for a can of Waterproofer into it.
Then, I can put release agents on the cone and mold, and put the wet, glass clad cone into the mold to cure.
I may have to enlarge the mold slightly to accommodate the additional mass, but I'm confident that I can handle that before it is an issue by adding a layer of something like nitrile glove or saran wrap to the cone prior to the making of the mold.
If this works out well, I will be able to do a scale TAN-SAM and Matra Magic 550.
I can also imagine using this method on a larger scale for my Seawolf NC. At that scale Duram's Wood Putty with wood glue enhancement would have to be the mold.
Wish me luck, because if this works like I think it will, I would gladly make these for other folks and give them away in the Yard Sale Section.

I've only done the fiberglass the foam cone that you turn on a lathe, then add layers of glass, and optionally dissolve the foam with gasoline to hollow it.

I have paper cones from the craft store I never tried.

Also used 2-part foam to take molds of the inside of cones (without a shoulder) with the intent of glassing them (another project I never got to) - they never turned out as nice as I hoped since the foam had what I can only describe as stretch marks.

TopRamen said:

Wish me luck

Click to expand...

I can't quite visualize what you're planning, but post pictures here as you make progress. And good luck!

Which craft store mold maker are you using?

Other low cost mold making techniques for fiberglass include plaster molds (I have used Ultracal plaster a few times with good success). Another plaster mold technique is to make a "mother/daughter" mold with a coating of RTV silicone brushed on the surface of your pattern to about 1/8" thick, allow it to cure and then add plaster to support the thin silicone mold. This works decently, especially if you have any surface detail that you need to capture.

For a blunt 2.6" cone, there is a classic model aircraft technique that would work well. You would need a well finished male nose cone pattern that is made to the correct size minus the thickness of your planned glass layup. Add your glass and resin to the surface of the pattern. Then, inflate a common toy latex balloon that will inflate to a size of 3-4 times the nose cone. Hold the mouth of the balloon, do not the it off.

Press the glass layup into the balloon and slowly let out a little air as the balloon wraps around the cone pattern. You want to end up with the entire layup and mold inside the balloon, with the skin of the deflated balloon stretched tightly over the layup and pattern. This sort of creates a poor mans rubber vacuum bag system for parts that will fit int a balloon. This is the old HobbyPoxy "EZ Does It" technique from the late 60s/early 70s. Can give a nice surface finish when done correctly.

You might have to cut the cone into two halves to get it off the pattern, but it is easy enough to do that. Them you simply tape the parts together and add another layer or two of glass tape along the seam inside to rejoin it.

Make a 5.1 VK 2.6 nc please. ..

John Coker had a great video for making a FG nosecone from a plug.

Kenny

John's "How To" video is great, but I don't have the time and resources to do it the right way, so I'm going to attempt to get by the way I think I can.
If it is a total failure, at least I tried and learned something from the process.

I'll research the crap out of this before I commit any resources to it. I've been doing that today on youtube. That place is full of ways to do what I want to do, I just have to adapt the methods to make rocket parts.
I'm learning about silicone molding and release agents.

Videos like this give me some ideas too.

[video=youtube;dBEK_Jyfvek]https://www.youtube.com/watch?v=dBEK_Jyfvek[/video]

[video=youtube;45YPlbgBCvE]https://www.youtube.com/watch?v=45YPlbgBCvE[/video]

KenRico said:

Make a 5.1 VK 2.6 nc please. ..

John Coker had a great video for making a FG nosecone from a plug.

Kenny

Click to expand...

I'm on track to be making whatever profile cone you need, and will be starting my cone making adventures in the 2.6" realm, so I'll gladly do that if you send me a template or Email it to me as a pdf.

I have a limitless supply of foam, and this extraordinary desire to create things that go on rockets.