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Prometheus Industries

The Big Boy Flamethrower

The Big Boy Flamethrower

$3,450.00 USD
$3,450.00 USD
Sale Sold out
Shipping calculated at checkout.

The Big Boy Flamethrower is NOT a boring flamethrower.  It has a 55+ foot range and comes with a lifetime warranty.  When you purchase your diesel flamethrower from Prometheus Industries, you have the option to return your flamethrower for a full refund, if you are not satisfied with it. Read our refund policy.

(Please allow 1-2 weeks before your order is shipped. We hand-assemble each flamethrower after you place your order)

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Technical Specifications

The big boy diesel flamethrower is composed of laser cut aluminum magnesium sheets, providing a strong lightweight frame capable of handling the intense heat generated by flamethrowing activities.

Burn rate: 3 gal/min

Heat energy: 137,381 BTU (full tank)

Chassis: 3D printed aluminum subframe

Fuel Cell Capacity: 1 gal

Maximum Range: 55ft+

Cavity Magnetron Ignition System; a 4000⁰ F arc is generated within a magnetic field creating a space charge wheel. The arc spins rapidly to catch every droplet of fuel creating the perfect conditions for igniting high Flashpoint fuels.

Dimensions: 40"x 15"x10"

Weight: 18lbs (fueled)

Each Order Includes

Fully assembled, handcrafted, Big Boy Flamethrower

Battery Charger (batteries included)

User Manual

Plasma Vortex Technology

Employing Plasma Vortex Techonology, The Big Boy produces a 30,000-volt electric arc which spins at hundreds of revolutions per second, and reaches a temperature of +4000°F.

This high-temperature plasma-based ignition mechanism distinguishes The Big Boy from all other flamethrower in the industry, enabling it to ignite 100% diesel fuel.

Built For Safety

The Big Boy Flamethrower was built to the highest standards of safety. Rather than using highly pressurized gas tanks, The Big Boy employs specially designed fuel pumps that prevent any chance of back burn. This means there's absolutely no risk of fire creeping up the fuel hose or causing a hazardous explosion.

Adding to its safety features, The Big Boy uses 100% Diesel fuel. Diesel's relatively high flashpoint, around 126°F, means that it doesn't produce stray, easily ignitable vapors, unlike conventional flamethrowers that use gasoline. This characteristic of diesel fuel further reduces the risk, making The Big Boy an exceptionally safe choice among Flamethrower.

Made in the USA

The Big Boy was designed and is being manufactured in the United States.

Flamethrower FAQ

Can You Use Diesel In A Flamethrower?

In some flamethrowers, you can use diesel fuel.  The majority of flamethrowers use some combination of gasoline or diesel. The Big Boy Flamethrower is the only one that runs 100% diesel fuel without the need to pressurize the fuel tank.

Why Use Diesel In A Flamethrower?

Prometheus Industries chose to use 100% diesel fuel as it has a high flash point (200 degrees).  This property of diesel fuel makes it extremely hard to ignite without additives or compression.

We offer the only electrical ignition system capable of reliably igniting pure diesel fuel; even the flames the diesel produces are not hot enough to consistently burn the fuel. This ensures that fire only hits the things you intend to. 

Why Is Gasoline Dangerous In Flamethrowers?

Gasoline is a much more volatile fuel, which makes it relatively easy to ignite in comparison to other fuels. This property however limits range and increases the chances of fire spreading in an unfavorable way.

Gasoline has a flashpoint of around - 50 degrees Fahrenheit, this means that at -50 degrees gasoline will produce sufficient vapors to ignite. In a temperate environment, gasoline will combust much more efficiently than diesel, efficiency while useful for cars or other devices is not necessarily a good thing in flamethrowers. While firing gasoline the flames will feel much hotter to the user as more of the fuel will be combusting closer to them, and more flames will also fall to the ground increasing the chances of wildfires and other undesirable circumstances. There is also a higher risk of explosion although it is not very likely.