# DIY Dry Ice Machine



## Jon Majors (Jan 24, 2019)

Does anyone have experience making their own dry ice machine? We are doing Les Mis in a few months and would like our stage covered in low lying fog in the beginning. Our stage is 52'x30'. Any recommendations on a DIY machine to cover this area? Is a heating element necessary? Thanks in advance for your input!

Jon


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## Colin (Jan 24, 2019)

I can't fathom an unheated solution working on your scale. You could build something using a submersible bucket heater, but the cost of materials alone probably approaches the cost of a rental, won't work as well, and will present more safety and liability issues. How many rehearsals and performances? Are you budgeting for the dry ice? That size stage is probably going to go through 3lbs of dry ice per minute. It can add up to more than the cost of a machine rental, which is why I bring it up - is the cost of the machine really the biggest issue?


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## Van (Jan 24, 2019)

I've built, IDK, 5-6 foggers over the years. the best version:
55 gallon drum.
55 gallon drum dolly. Has to support 500 pounds.
Small, submersible, recirculating pump.
Squirrel cage fan, mounts on top, drives air into the machine and forces fog out.
two water heater elements.
6" dryer vent hose.
6" dryer vent hose adapter <6"aluminum flange, mounted above the water line>
Various parts to make the hatch on top. Hinge, latch, gasket material.
Watertight quad-box.
Water-tight switches to control Fan, Pump and heater elements.
Various SO
Water heater jacket. 
spigot or flange and plug for bottom of drum to drain water.
A lot of RTV or "Flex Seal"

It's really easy, kind of time consuming and you have to be sure all your electrical connections are hard and water-tight. You don't want loose wires, flex conduit or the like getting caught on anything. It will eat up a TON of dry ice. 

BTW do not store Dry ice in a sealed container without a gas relief device, it will explode.


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## venuetech (Jan 24, 2019)

I’m not great on fog but you may need more than one machine to quickly cover this space. At least two.


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## RonHebbard (Jan 24, 2019)

Van said:


> I've built, IDK, 5-6 foggers over the years. the best version:
> 55 gallon drum.
> 55 gallon drum dolly. Has to support 500 pounds.
> Small, submersible, recirculating pump.
> ...


 *@Jon Majors @Colin * *@Van* and @venuetech Posting in agreement and support with *ALL* of the above.
In the late 1970's our Canadian National Ballet built a pair as Van described. Each 55 gallon drum was heated with two 20 amp 120 volt two Kw immersion heaters requiring four of our 20 amp non-dims to preheat the two units, one on each side of the stage. Over the course of a one week stay I fetched many fifty pound blocks of dry ice from a wholesale welding supply shop I passed on my way in from Burlington. The supplier would slice the blocks approximately 1" thick on a large band saw then wrap them in news paper for their ride to the theatre. Dry ice sublimates directly from a solid to a hazardous gas thus I drove with my windows cracked open even between Christmas and New Years. Four Kw of electric heat per drum would bring tap water up to temperature in about an hour, (You'll want to include thermometers on your drums as well so you can note the temperature of their water without needing to open them and lose precious heat.) Plunging the internal wire basket full of crushed dry ice two or three times rapidly chilled the water to a useless temperature. Over the course of the National's 'Nut Cracker' visiting for several years I became quite adept at smashing and crushing sliced 50 pound blocks of dry ice and loading the internal wire baskets.
*Moving on to the explosion hazard*.
Some years later an amateur friend built himself a couple of slightly smaller dry ice foggers for spring dance recital season using drums of approximately 40 gallons. His machines worked well but one of his clients rented a local high school with plans to load in and set up on a Thursday and Friday, focus and rehearse Friday evening then run performances twice on Saturday and twice on Sunday. As his dry ice supplier was closed on the weekend my amateur acquaintance purchased an even smaller drum complete with a tight fitting lid and a latching metal surrounding ring. He lined his smaller drum with insulation and had his supplier fill it to the brim with dry ice. He didn't know Van so he sealed it up tight and left it in a locked storeroom off stage left Friday evening. Imagine his surprise when the sealed and secured lid was missing from his small drum Saturday afternoon with only the barest trace of dry ice remaining. The drum must've gone off like a bomb; its sides were bulging and when he finally found his bulging lid it was on top of an approximately six foot tall storage cupboard within the storeroom and there was evidence of damage to the ceiling above where the sealed drum of dry ice had been stored.
*Yep!* *Blew up like a bomb!!* That'd be science for you as *@BillConnerFASTC* would tell you.
Posting from north of Donald's walls. *@Jon Majors* It may be both possible and easy but wait until you start paying for all of that dry ice!
*P.S.* If you're the National Ballet and desperate for dry ice on a weekend, and if the mayor calls the Red Cross and pleads on your behalf, you can manage to acquire dry ice they manufacture in small quantities for transporting blood and organs for transplants.
Toodleoo!
Ron Hebbard


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## Colin (Jan 24, 2019)

venuetech said:


> I’m not great on fog but you may need more than one machine to quickly cover this space. At least two.



Under the right circumstances one Aquafog could definitely handle that size stage, and perhaps even a single Peasouper/Nimbus style machine too (for just a few minutes) but yes I'd want one per side. With just one machine you may fill the stage but the source will be very apparent, and that can sort of ruin the illusion. Plus, movement on stage dissipates the fog quickly so you may test the effect without cast on stage and think you've got plenty, and then when people start moving around you realize you need more. More machines means you don't have to run them full-out, so the water holds a useable temperature a little longer, the fog doesn't billow out of the machine as violently so each source is less obvious, and you get less water spitting from the outlet causing slipping hazards etc.


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## Colin (Jan 24, 2019)

To be thorough, as others have begun to explain, the safety issues any dry ice effect brings up are:

- Frostbite/burns from contact with something -109.3F, and from scalding hot water in a necessarily not spill-proof container
- Suffocation due to reduced oxygen available near the floor during the effect (also consider how front rows of seating are affected) or anywhere a sizable quantity of dry ice is stored without adequate ventilation
- Explosion from inadequate venting of storage containers
- Trip, slip and fall hazards from reduced visibility near the floor and stage/stair/platform edges, and from moisture produced by the effect
- Other issues from water on stage near electrified equipment, and near stage curtains that may have their flame retardant treatments compromised should they get wet
- Obscured emergency egress visibility (almost as unlikely as tripping a smoke sensor with dry ice fog, but a top reason a fire marshal takes interest when they hear "fog effect")
- And then if you're making your own machine, all sorts of other things related to amateur electrical work plus heating elements plus water

Regardless of how the effect is achieved, it's wise to have a written hazard assessment and safety plan, conduct training, and invite your fire marshal and EHS department to check it out so you don't surprise them and they don't surprise you. 

All things the DIY question brings up, because with really good commercial machines available the DIY option tends to be a sign that someone is seeking to cut costs/corners. But maybe not.


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## BillConnerFASTC (Jan 24, 2019)

Van said:


> I've built, IDK, 5-6 foggers over the years. the best version:
> 55 gallon drum.
> 55 gallon drum dolly. Has to support 500 pounds.
> Small, submersible, recirculating pump.
> ...




I built one - or a pair - like this in grad school in I think 1977. I was quite pleases it was still in inventory and used sometime after 2000. I'm told it has since been removed from service. Like a bubble machine I also built a pair of for I think the original production of the 1940s Radio Hour. What a hoot those were. Too many bubbles - had to figure out a way to throttle the down. Those were some days...


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## Ancient Engineer (Jan 24, 2019)

Yea, the CO2 can slide off the stage right into the pit and fill it up and cause the musicians (heavy breathers) to get sick/dead.

It will displace air and just hang there until disrupted. We put box fans in the pit on low speed to just keep cycling the air into the space.

There wasn't any grumping above the background level.


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## mbrown3039 (Jan 30, 2019)

You can fake dry ice with a regular fogger if you chill the output. It doesn't have quite the same "cling" or density as dry ice, but it is *much* cheaper and exponentially safer: find 3 - 4 regular coolers (that are roughly the same size) at Goodwill, yard sales, whatever. Attach them to each other end-to-end (if they're plastic you can try to glue them together using PVC cement, but you can also just bolt them together), then drill a 2" hole through them all of them at a uniform height so you can push a single piece of 2" electrical (metallic) conduit through them -- it should hang out 3-4" at either end. Set up a regular fog machine so that the nozzle is as centered as possible inside one end of the pipe, then fill all of the coolers with regular ice at leas an hour before use (it's important that there be space under the pipe in all of the cooler for ice to be able to completely surround the pipe). You may want to seal the collar around the fog machine nozzle to the outside of the conduit to prevent leakage, but otherwise you're all set. As the machine generates fog it is chilled by the ice and upon dispersion from the pipe settles and hangs for a while. Like I said, its not the same as dry ice, but the investment is so minimal I've thrown away the ones I've made previously. And, no CO2.


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## Van (Jan 30, 2019)

mbrown3039 said:


> You can fake dry ice with a regular fogger if you chill the output. It doesn't have quite the same "cling" or density as dry ice, but it is *much* cheaper and exponentially safer: find 3 - 4 regular coolers (that are roughly the same size) at Goodwill, yard sales, whatever. Attach them to each other end-to-end (if they're plastic you can try to glue them together using PVC cement, but you can also just bolt them together), then drill a 2" hole through them all of them at a uniform height so you can push a single piece of 2" electrical (metallic) conduit through them -- it should hang out 3-4" at either end. Set up a regular fog machine so that the nozzle is as centered as possible inside one end of the pipe, then fill all of the coolers with regular ice at leas an hour before use (it's important that there be space under the pipe in all of the cooler for ice to be able to completely surround the pipe). You may want to seal the collar around the fog machine nozzle to the outside of the conduit to prevent leakage, but otherwise you're all set. As the machine generates fog it is chilled by the ice and upon dispersion from the pipe settles and hangs for a while. Like I said, its not the same as dry ice, but the investment is so minimal I've thrown away the ones I've made previously. And, no CO2.


I posted a How To for an Ice cooler chiller on here. 

You do NOT want seal anything against the fog machine. Any type of external cooler needs to have a fog hose adapter to allow it to pull in external air via venturi effect.


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