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Small mushroom cloud

Discussion in 'Special Effects' started by aemeeich, Apr 24, 2009.

  1. aemeeich

    aemeeich Member

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    I am trying to figure out a way to make a small device that will create a safe small mushroom cloud of smoke. The device can be hidden in a cauldron. I know that flash pots are out of the question since it happens so close to actors. The show we are doing is "Once Upon A Mattress". Near the end of the show, the wizard and queen make a sleeping potion to put the princess to sleep. According to the script, the princess' head is supposed to be enveloped by the cloud.

    Does anyone have any suggestions to make a small cloud? If her head can't be in the cloud, I'm ok with that.

    Thanks for any help.

    Michael
     
  2. cprted

    cprted Active Member

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    What about a fogger?
     
  3. Van

    Van CBMod CB Mods Premium Member

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    We had a similar question a while back, I think. I'm remembering I answered something along the lines of one of those toys looks like a ray gun. You pull the trigger and a chamber fills with fog, then you pull and release this lever on the back which causes a membrane to snap forward and the thing shoots out smoke rings. You could probably google " smoke ring gun" and find it. Anyway, using that as a basis for your engineering might be a good idea. the mushroom cloud effect is going to be best achieved by filling a cylinder with smoke then releasing air pressure below it. This is definately a HVLP aplication < High volume, low pressure.
    My only caveat, and I think you already see this comming, is the dangers of the actress winding up with something getting in her eyes. My normal suggestion for a convincing dust on stage is rye flour, low incidence of allergic reaction, very fine particles, but in this case I don't think it would work well on the off chance that she wind up with something in her eyes or inhaling a large quantity.

    Hope that helps a little. I'm gonna ponder this one a bit as I sit through techs this week.
     
  4. derekleffew

    derekleffew Resident Curmudgeon Senior Team Premium Member

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  5. aemeeich

    aemeeich Member

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    Thanks for the suggestions so far. The ring shooter shows some potential promise after some modifications.

    derekleffew - I originally thought of the smoke in a can, and I just picked up a can of it this afternoon. It doesn't really work for creating a cloud. It comes out to thin and slow to look like a mushroom cloud. It is also pretty noisy so her microphone would pick it up too much.

    Michael
     
  6. FatherMurphy

    FatherMurphy Active Member

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    I did an 'Odd Couple' (or was it a dinner theater farce?) some years back that used a bit of dry ice in a covered pan to simulate a burned food dish. Incense cones put out quite a bit of smoke when first lit, perhaps putting them in a lidded dish would load up the air inside the dish, and removing the lid vertically would draw the smoke up towards the actor's head.

    [Insert standard warnings for 'dry ice handling' and 'burning materials on stage' here]
     
  7. gafftaper

    gafftaper Senior Team Senior Team Fight Leukemia

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    When i did "Once Upon a Mattress" I used a cauldren, with a pot of hot water and some dry ice. They mix the potion and we see stuff bubbling out of the pot. Had a bunch of crazy red lighting with weird shadows. No smoke trick's around the actress' face... to difficult, dangerous, and expensive.

    There are other fire and smoke options out there in the world of Magic that can be safe when used properly by trained people. Contact your local magic shop for more information. Be sure to talk to your fire marshal about local regulations before purchasing any of these tricks. Nothing more on that topic can be discussed here due to TOS regulations, go to your local magic shop.

    You could consider doing it with light too...what about something like this or this in a gobo rotator?
     
    Last edited: Apr 25, 2009
  8. willbb123

    willbb123 Active Member

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    I've never done this effect, but I have an idea that works in my head.

    Get a 5 gallon bucket, place it upside down, cut the bottom out, replace it with a door. Fill the bucket with smoke, then when you want the effect pull open the trap door.

    I'm not sure if the smoke will fly out like I think it will. Probably wont :rolleyes:. You could take a small computer fan and put it in the bottom of the upside down bucket. That way you have a bucket full of smoke waiting there.
     
  9. epimetheus

    epimetheus Well-Known Member

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    I'm certainly no expert here, but I did this chemistry experiment in high school with a very fine, non-flammable powder...

    Big Boom!

    Think grain silo explosion. Probably not a good thing with electrics overhead.
     
  10. renegadeblack

    renegadeblack Active Member

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    ThinkGeek :: Zero Fog Blaster

    Rewire the trigger with either a dmx low voltage relay or have some stage hand with something (maybe an extended trigger) elsewhere and trigger it.

    Disclaimer: I've never used one of these, I don't know whether or not the trigger is electronic, I don't know if it works pointing straight up, but you may want to look into it.
     
  11. NickJones

    NickJones Active Member

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    Yeah, renegadeblack's soloution would be your best bet.
    Nick
     
  12. RichMoore

    RichMoore Member

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    What about suspending a bucket with dry ice and water inside the cauldron, which will fill the cauldron with vapor....then for the bottom of the cauldron, use some sort of typanic membrane, rubber sheet...old bass drum head...something that can be struck from the outside of the bottom and will compress upward a bit, forcing the vapor upward and out.

    Or, place inside the cauldron a piece of foam core that can act as a piston that will force the vapor from the cauldron when a lever, that is connected to the piston through a hole in the bottom of the cauldron, is stepped on.

    Have fun and good luck.

    Rich
     
  13. awhaley

    awhaley Member

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    I know it was said in the second post... but it didn't get much replay time, so...

    I'd seriously consider renting a high-output dmx-controlled fogger. They can produce QUITE a puff of smoke on command and are reasonably safe around actors. DO make sure you're dealing with a high quality one designed for theatre, and not a DJ grade one, as the DJ grade foggers occasionally refuse to respond to commands while they reheat the element...

    If that really won't work for your effect, I think contacting the local magic store was an excellent suggestion!

    Art Whaley
    Art Whaley Design
     
  14. aemeeich

    aemeeich Member

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    Sorry for the delay on responding with a follow-up, I got hung up with finishing up events at the end of teh school year, and a pretty intense work schedule.

    What I ended up doing was taking a small 400w DJ fog machine I had sitting around and putting that below the "table" they were using for the potion bowl. I modified the unit with an external single button switch. I wired the switch so that it would run the pump whenever it was pressed, even if the unit wasn't preheated. I also put a light in the box so that when the unit was up to temperature, the light would come on. This ensured that when it was time to have the burst of fog, even if the unit was reheating, the fog would come out on cue.

    I put the fog machine under the stool, with a elbow and 2" pvc pipe to direct the fog straight up. The pipe was hidden by the bowl on top of the stool.

    [​IMG]
    [​IMG]

    It worked very well and gave a nice puff of smoke that formed a pretty decent mushroom cloud. There wasn't enough room under the stool to use a larger output fog machine like my rosco 1600 or 1700.

    The props crew/director didn't spend alot of time on the stool since they came up with the idea very last minute, so it didn't look as good as possible, but from the audience's viewpoint, it wasn't terrible. I wish I could have spruced up the rig a bit more, but I just didn't have the time with everything else I had to do.

    I also put my camera flash behind the bowl. The plan was to have the actress hit the fog button, and the pilot button on the flash at the same time. There should have been a flash of light in the princess's face, then the fog would rise, but the actress in charge of the buttons never was able to get the timing quite right. During rehearsals, she usually would hit the flash after the fog had already risen. During the performances, she just never did the flash.

    Unfortunately, they got a bit carried away with the dry ice and put way too much in. The dry ice was dumped into a bowl of hot water when the potion was made, then the mushroom cloud was supposed to rise. Because there was so much dry ice fog falling on top of the pvc pipe outlet, the mushroom cloud had a hard time making it up so it didn't look as compact and thick as it was without any obstructions.

    The night i took these pictures was the closing night, so they went all out with the dry ice and it was thicker than any other night, so in this picture, you can barely see the mushroom cloud. The other nights it came out a little bit better, but still not as well as I would have liked.

    [​IMG]
    [​IMG]

    Thanks for everyone's suggestions and input. It was greatly appreciated

    Michael
     

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