Historically blacksmiths have used a number of methods to deliver air flow to the fire:
- Human Lungs
- Hand Cranked Fan
- Electric Blowers
In the early days, it was common for a blacksmith’s apprentice to use their lungs to blow air into a hollow tube, directly into the base of the fire. This method was not very effective as the majority of the oxygen they inhaled would get absorbed by the lungs, and the exhalation contained a lot of carbon dioxide which did not help the fire. Not only that – heavy breathing would quickly make apprentices dizzy from hyperventilation and could result in them passing out (and possibly falling into the fire!) Many apprentices would have begun their training before the age of ten. Life was tough for a blacksmith apprentice in those days, for sure. This was not an effective method, and so an alternative was sought…
The classical medieval bellows was a device made from wood and leather and was used to push air into the fire to allow the furnace to reach a high enough temperature to make iron melt. The bellows were definitely an improvement. They expelled as much oxygen out as they took in and so fed the fire with much more oxygen than human lungs could. However, life did not improve much for our young apprentice as he now had the job of operating the bellows – a dull and gruelling task which lasted for hours and the repetitive movements were enough to make anyone’s arms and back ache.
Bellows are constructed from two wooden panels, one with a hole cut in the centre. The paddles are connected with a hinge. A leather flap that only opened one way was secured to the hole in one of the paddles. A leather bag was fixed between the paddles and a nozzle set at the head. The air would come in through the hole in one of the paddles when the bellows were pulled apart. When they were pushed back towards each other, the air would be expelled out the nozzle and into the furnace’s fire.
The bellows shown in the image here are single-chambered hand-operated bellows. Most blacksmiths would have used the much bigger double-chambered bellows. As the name suggests, these had two air-tight chambers instead of one and were much more efficient and offered a more constant air flow.
Bellows began to be displaced as the sole source of air blast in the late 19th century when mass produced cast iron hand-cranked blowers were introduced. The centrifugal blower was invented around 1850 and has pretty much replaced bellows due in part to its compact size relative to the bellows it replaced. Today, blacksmithing bellows are antique collectable items.
As the handle of the hand-cranked blower is turned, the fan blades whirl in their cast-iron housing and move air with centrifugal force, pushing air outward into the fan housing and the air delivery pipe. A series of gears or pulleys are often used to step up the number of turns or rotations the fan wheel makes for each turn of the crank.
Forge blowers with an electric motor offer the blacksmith a constant, consistent stream of air that can easily be adjusted to suit the work requirements. Electric fans come with a speed control function, a way of controlling the amount of air being fed into the fire.
electric motor fan
ACI Forge Fans & Blowers
Our forge fan units enable blacksmiths to efficiently and effectively raise and lower the temperature control of forges – with the added benefit of units being very quiet, compact, robust and reliable. We offer a range of fans suitable for use in blacksmith forge applications.