# Blowing up a battleship



## Wayne Roth (Nov 3, 2016)

Our show is based around Perl harbor attack. I need to blow up a battleship. I am using fog and lighting for fire and compressed air confetti cannons for the explosion. I looking for something to put it the 2 inch cannon to look like the ship exploding. We need to reset within 1 hour for back to back shows so needs to be easy to clean. I am thinking about sawdust or rye flower. Need more ideas...


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## JohnD (Nov 3, 2016)

One major safety concern for using air borne items like sawdust or flours is that they are very flammable, explosive even.


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## Wayne Roth (Nov 3, 2016)

JohnD said:


> One major safety concern for using air borne items like sawdust or flours is that they are very flammable, explosive even.


My confetti is treated with a fire retardant. Is there a treatment I could use with sawdust?


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## EdSavoie (Nov 3, 2016)

Mythbusters Sawdust Cannon

I'm not sure such a treatment exists. Wouldn't it cause the sawdust to clump?

Even if it worked, not sure if launching heaps of sawdust into the air is a very good idea. Sawdust in the eye isn't very fun.


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## TheaterEd (Nov 3, 2016)

Wayne Roth said:


> My confetti is treated with a fire retardant. Is there a treatment I could use with sawdust?



Nope Here is an example of sawdust in the air near a fire source it's not the flamability, its the dispersal.

As John stated, Sawdust in the air is a MASSIVE fire/explosion hazard, and any small airborne particulate is bad news for any creature that breathes. Can you go with larger pieces of a light weight foam? They'll be easier to clean up, and easier for the audience to see. I'm thinking something like this so you have random shapes of debris.


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## Tom Andrews (Nov 3, 2016)

You CAN make your sawdust appropriately flame retardant by treating it with Roscoflamex WD. However, you'd need to achieve sufficient/complete saturation of the wood particles, so it'll be a messy and lengthy process to treat and dry it all. Also, the treated sawdust will have a different weight than untreated sawdust, and tend to agglomerate together (i.e. stick together), and may not 'fly' or float as you'd imagine. If you want to go that route, do some testing before embarking on doing large batches. 

Wheat flour is definitely off the table, as you can't treat it without turning it into a ball of fire retardant dough. 

I agree with the suggestion for larger pieces. They'll also be easier to treat to be FR. If you use foam, make sure it's already FR. There are many sources for FR foam out there. Make sure it has the proper testing for your needs. 

Other considerations are OSHA and consumer requirements regarding airborne particulates, but other people have expertise in that area.


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## BillConnerFASTC (Nov 3, 2016)

Ground cork? Maybe not fine enough.


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## Van (Nov 4, 2016)

BillConnerFASTC said:


> Ground cork? Maybe not fine enough.


Ground cork works wonderfully! 
Cork is what was used on Ka or O or one of those Canadian productions in Las Vegas to simulate rain. There is a company in New England that sells the stuff buy the truckload to Cirque but they also sell smaller quantities. 

I will echo the others sentiment though, any small particulate in the air has potential for explosion, and or serious irritation of performers senses. Even Rye flour would become a serious irritant if you treated it with flamex, dried it, then sifted it, then shot it in the air. the nasty salts in it would seriously sting the eyes and inhaling that stuff is.... Ick! I'd stick to bigger chunks, personally.


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## BillConnerFASTC (Nov 4, 2016)

The cork is used for Ka for the sand on the sand table. I'm told that concept - the sand, the beach, and it tipping to pour the sand off - was the origin of the whole sand table that tilts, spins, and raises up and down. Cork was found to be the most inert, dustless, and safe substance. Googled and found this: http://www.marylandcork.com/default.aspx. I was looking for toxicity and flammability data and gave up.


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