The "Fog of War" Comes to the Office

Mood. Atmosphere. Aaahmmbiance. Subtle shifts in the environment that change the feel of a room (or cube) from "warm and inviting" to "cold and clinical" to "Hear me, Prince of Darkness." The fog machine is your absolute go-to mechanism for achieving that crucial combination of fantasy, intrigue, and impending ritual dismemberment so essential in business negotiation today.

They're a lot of fun to build, too. A fogger is an inherently simple mechanism that can become insanely convoluted in the blink of an eye. This is a good thing. Atmosphere is one thing. Atmosphere created by a dangerously complicated-looking apparatus is entirely another. There's a fair bit of foraging for parts involved in this little endeavour, regardless of how you choose to approach the subassemblies, so preplanning is either the best or worst idea ever, depending on how broadly you wanna embrace the great cosmic random. If it was me, I'd wing it completely and design on the bench. Although it is entirely possible to design a sleek and compact fog generator, the coolness factor is noticeably diminished.

What We're Building

We're going old-school here, with a design that vapourizes a glycerin/water mixture to produce fog. Large-scale commercial foggers evaporate dry ice in a hot water bath to achieve the same end without the "low-budget mid-80s Goth club" smell of glycerin-based ambience. You can adapt this design to that technology by enlarging your fog chamber, putting a pot of water on the fog chamber's hot surface, and hand-feeding ice-house dry ice into it during use. The rest of the delivery mechanism remains the same. It's your decision, but startup time is considerably longer with CO2-based fog as you wait for the water bath to heat up, and glycerin is generally easier to source quickly than dry ice.

Pinning the mechanism out on the tar pan, you'll find that it works like this. Fog juice (A) drips through valve (B) onto a hot surface (C) in a closed container, which creates hot fog (D). Hot fog rises, which is not the ground-hugging effect you're looking for. Fortunately, there's airflow (E) to blow the hot fog through an internally baffled (F, G, and H, respectively) intercooler full of ice (I, collectively) and out the exhaust. Cold fog (J) hugs the ground like a goff in a cemetery. Robert Smith (K) would approve.