Making a crystal like sphere is something I've seen commonly used for cosplay- be it for ornaments in a hair or a physical part of the costume. Sometimes you'll see styrofoam balls, clay, resin gems, and other ways that people make them- all of which can be not smooth, hard, and sometimes heavy. This tutorial is to show a simple way on making a designed sphere/stone/orb that is shiny and light by mixing paints with spray paints.
When I worked in a hobby store when I was in High School I was one of the people that did the commission designed bodies for the nitro cars sold in the stores. These were our preferred choice brands since the enamel and lacquer paints were plastic friendly. Our advantage as cosplayers is we do not need a ton of spray paint for any of our projects, so the small bottles they come in not only allow for spraying in small areas but they are also nice fit in our hands. They are also extremely shiny (the lacquer being glittery) and tend to be a reasonable price compared to the big can brands (especially when you can use 40-50% coupons at Michaels.)
Unless you plan on keeping them, use a pair of wire cutters to cut them off from the base. Depending on the strength of the plastic it can be hard to get it off fully from the base. Use sandpaper or a sanding block to try and flatten it out, or at least get the sharp edges rounded out. Do not sand too hard or you'll scratch the surface of the sphere instead.
If you're making a symbol or a pattern, it's best to have something against the sphere in the size you want in order to get the shape properly on a curved surface. Eyeballing that can be a big issue especially with mirror imaged symbols and such.
IMPORTANT: Mirror image mirror image mirror image! When you print out your pattern you want to be sure it is backwards! If not, your image on the outside of the sphere will be backwards instead.
Use blue painters tape to put the mirror image onto the sphere. When you've got it where and how you want it use it as a pattern to paint with acrylic on the inside of the orb. Acrylic paint is thicker than something than a marker or another paint, meaning spray paint will not come through the symbol. Make sure to paint at least two layers to ensure that it is thick enough to not have paint bleed. Use a light to check it.
To protect the outside edge while you're spray painting, you're going to want to put a length of blue painters tape around the outside. Do not worry about evenness anywhere else but on the very edge. Try not to pull too far over the edge (if at all) to reduce a chance of spray gather and potential dripping on the outside.
Be sure not to cover the very bottom of the orb since this gives you a window from the right side of the orb on how the colors are layering which is really importance for comparison.
After you're done taping you're going to have a crapton of fingerprints on the inside. If your hands weren't spotless you're going to have marks there that may show through the paint. Either use a microfiber cloth or some other cleaning cloth to get rid of excess marks on the inside. This also can really help for dust or animal hair (like cat haiiiiir).
Things to remember when setting up a spray area: ventilation, floor coverage, behind coverage. Wherever you're spraying you'll want to make sure there is air flow so that the fumes of the cans escape (unless you are outside) and you'll want ground coverage and a background coverage for the spray that passes your hands. Spraying directly into the ground proves to be difficult at times. If you have a large cardboard box that's an amazing place to spray into.
Most importantly its better to spray when the sun is out (with some cloud cover) to help you better estimate what the final colors are going to look like in the daylight.
Be sure to put a glove on the hand holding the orb since you will be spraying into your hand and will most likely hit it. Always make sure to shake the spray as much as needed and give a test spritz somewhere in your spray area to make sure it is not clogged and not spattering in some way.
Now how your orb looks will completely depend on what sort of color mixture you want on the inside, so here are a few tips in order to get the perfect coverage.
Do not remove the tape until you are satisfied with the color! Use the windows at the bottom instead.
Place the orb on a flat surface OR against the other edge that connects with it to see if you have the color you want. By doing this you are able to see how the color holds when it is enclosed fully. Place the flat ends in both the sunlight and the shade to get a real good grasp of how the light affects the color. You can continue spraying layers after this point.
This was a fault I learned in making my first batch. To ensure I got the color I wanted I held up the half a sphere up to the sunlight to make sure how the light would pierce through this. What I had forgotten was the fact that another side goes over that and the sun has to go through the outside, not the backside. As you can see in the two pictures there is an enormous difference between the two.
Some cans will tell you how long the paint needs to dry, but to really ensure that the layers are as dry as they can be aim for 4 or more hours. Place the orbs in a safe location if you have animals so that they do not go sniffing around or even worse, getting hair in the drying paint. Keep it out of direct sunlight in order to avoid cracking or unevenness in drying. If it is warm outside try to keep the orbs drying inside where it is cooler to avoid the painters tape from melting unneeded sticky residue onto the outside, and keep the paint on there until it is completely dry to avoid you possibly mucking up the inside taking it off.
Warning: If you attempt to put the two halves together too soon (before it is too dry) you will fuse them together pretty much permanently. Wait longer for drying if you intend on pulling these apart often.
Take off the tape, put the two halves together, and bask in all the glory! You've officially made yourself a shiny orb of some sort! Possibly without inhaling too many deadly fumes!
All of the following colors (unless noted) are Testors Spray Enamel (E) or Lacquer (L).
* notates a very light layer for blending purposes