How do I get a solid balloon shape? Using a 3 Foot diameter latex balloon, need to fill with a solid, smooth material?

First:  Thank You Already for Considering helping me.
I need the shape of the Inside of the balloon - not the outside like papermache'. I tried Canned Foam Insulation "Great Stuff" brand; but it didn't expand and solidify.  Then I need to cut it in half to get a hemi-sphere / hemi-balloon shape.  A shape like half an egg, but 30" long, 19" wide, and 9" deep if laid on the flat side.
Will Gorrilla Glue puff up and stretch out the balloon? 
Is there some kind of expanding urethane that doesn't need free air to cure?
Will a rubber mold making liquid like Vytaflex fill a balloon to it's "real shape" and cure inside without air?  http://www.youtube.com/v/MJ9lgZ3V90o&autoplay=1 is a video of making a sink mold from an existing vessel sink.  But I don't have an original of this shape to make a copy of.
Ice isn't permanent enough, but would be the perfect slick surface texture.  I don't have the tools to cut a 30x19" sphereoid in half neatly.
The goal is to get a solid shape with a smooth surface to use as a mold for pouring material over to achieve a "bowl" shape with a very smooth interior surface and a hand formed outer surface.
thanks again


Re-design6 years ago
Mix about a quart of 15 minute epoxy or quick setting casting resin, pour it into your balloon. Inflate the balloon to the size you want. then rotate the balloon so that ALL of the inside surface is coated with epoxy.

After the epoxy cures you will have a thin casting of the inside of the balloon. Make a small hole in the balloon and pour more epoxy inside and rotate as before after covering the opening.

Now you should have a shell that you can cut open and reinforce with strips of fiberglass cloth and more resin.

Wear really good eye protection, face mask, gloves and old cloths.
rickharris6 years ago