How to build an inflatable "brain" costume for stage - seeking ideas?

Hi all,

a friend of mine asked me to help him design and build a costume for a stage show he's doing; he will be wearing a monster mask and needs an inflatable "brain" to suddenly inflate (note, he changes costumes every 5-10 minutes during the show so it's something that needs to be fairly portable and easy to change into). We tried using CO2 canisters with balloons, a good effect but not nearly big enough. I'm thinking about some kind of air pig with a valve that he can clip a connecting hose to. If anyone has done anything like this or has a good recommendation I'd love to hear! Many thanks,


Picture of How to build an inflatable
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RavensCraft4 years ago
Sculpt a giant brain out of soft spongy foam using a hot wire tool.
Then compress the giant brain by hand and stuff it
into something that will hold it compressed. Perhaps a gray
plastic bag. or clear nylon monofilament net.
The actor then grabs his head and releases the compacted cranial matter from compacting device.
that could work - stuff it in a balloon, then vacuum the air out so it compresses; it will naturally inflate when the valve is triggered; need to vac it to reset it.
frollard4 years ago
Our local dollar store has balloons that are about 9 inches across deflated, and inflated go up to about 3-4 feet diameter...seems like a starting point for the size; the only hard part is getting THAT much high pressure air anywhere near the actor; an air compressor would take a good dozen seconds to fill something like that.
damianzuch (author)  frollard4 years ago
Hmm, you think it would take that long? I was thinking (haven't tried it yet though) that once he released the valve it would empty the air pig almost immediately...? I should at least try it out... Also, with the balloons, I'm seeking ideas on how to make one not come out perfectly spherical, I'm hoping to get some of that brain pattern into it...
You could try cutting out the brain pattern from another balloon, and rubber-cementing it onto the main balloon; the thicker shape will have more support and stretch less, causing bulges and divots.
damianzuch (author)  frollard4 years ago
This I like! I'm going to try it; I think it's a great idea. Also, I spoke with my friend about the build, he's not as tied to the idea of the brain expanding instantly; he would be happy if it gradually got bigger throughout the five-ten minutes he's wearing the mask. This permits the use of an electric mattress inflator - I'll have to experiment with it.
iceng frollard4 years ago
Do 2 balloons in the main balloon.