Picture of Make a Foam Sphere!

We're going to learn how to make a sphere out of insulation foam (extruded polystyrene). What you do with that sphere is your own business.

Step 1: Materials 'n Such

Picture of Materials 'n Such

You're going to need:

Insulation foam - found at you local home supply store. I used 4'x8'x2" sheets. around 4 of them for this sphere. (sorry i don't know exactly how many, i was also working on another project simultaneously

Spray Adhesive - Make sure it's compatible with foam. I recommend Loctite High Performance Spray Adhesive , that stuff worked great, I was surprised how well it worked.

Cutting Tools - Sure, you could use a serrated bread knife, in fact that will come in handy later, but for the major cutting, do yourself a favour and buy a hand Jigsaw! I spent way too much effort cutting out large circles with a knife when I realized that tools had been invented to make life easier, and it did. My jigsaw cost about 30 bucks, and it was so worth it.

Large Chalkboard Compass - I found mine at a school supplies shop. this was a real life-saver. I first tried a string on a nail, but it was inaccurate and a real pain to use. The large compass made drawing large circles a breeze. I know, imagine that, tools made for our convenience.

Shaving/Sanding tools - get a hand rasp like the one pictured, It was the most efficient and least blister inducing. also get a couple different grades of sand-paper, coarse and fine. Use smaller electric sanders if you like.

Measuring Tape

Sharpies - Sharpies are the best.

Tunes! - get some good tunes goin! ask for me for recommendations, go ahead.

This may help as well. This ball would be just over 44 inches tall. These would be the radius of each ring.

:) Steph

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Rushmoore2 months ago

Thanks dude! This is an awesome instructable!

Eh Lie Us!1 year ago

clever clever. . .

meranyrae2 years ago
This is great! I want to make my sweetie a death star for xmas and even tho mine won't be quite so big, the concept is similar. I was thinking of decoupaging a childs rubber ball and then popping it inside and threading lights inside but wasn't sure if it would be stable enough. This gives me great ideas. Thanks for sharing!
seamster3 years ago
Thanks for posting this. It's the kind of thing I'll probably end up making at some point, for whatever reason, and you shared some good tips here. (Specifically how you laid out the measuring circle to help get all the layers the right size--very clever.)
-Ranger (author)  seamster3 years ago
Thanks, and You're Welcome. Hope it comes in handy some time.
mikeasaurus3 years ago
Spheres are difficult to make, yours looks good!
So...what are you going to do with it?
-Ranger (author)  mikeasaurus3 years ago
Mine was turned into a costume, a globe of sorts. It was for a commercial someone was making.