Cannon foundry at the Jaigarh Fort was the brain child of Maharaja Man Singh Ji-I. Its plans were based on his extensive knowledge of cannons gleaned on his Kabul campaign in the 16th century as commander of Akbar’s army. It covers an area of about 9000 square feet. The furnace and the drilling complex are its two major parts.The furnace its self is of the dimensions of 24 X 12 X 10 feet. It is an open hearth furnace where very high temperatures of about 1000 to 1200 degree Celsius can be attained.There are two charging windows and three chimneys.The hearth of the furnace is oval and made of fire bricks and clay.There are two opening in its ceiling which open into the chimneys above.The hearth has a small 2X2 feet window which opens into the pit outside so that the molten metal can fall into the mould and take its shape. A 72 feet long tunnel in the lower part of the furnace worked as a wind tunnel.
The Drilling Complex is an octagonal room with the ceiling at the height of 31 feet where the barrels of cannons moulded in the foundry were bored. Four pairs of oxen were used to turn the levers of the machine which bored the barrel of a cannon in the making.
The moulds used for casting the barrel of the cannon were made in two halves and joined together after layering the inside with clay mixed with adhesives, granular sand ,silica,mica,coal etc. These moulds were also bound together with strips of iron so that the mould could stand the pressure of molten metal.
The Jaivan was the most famous cannon cast at the Jaigarh Cannon Foundry.It is the largest cannon on wheels in the world. The height of the front wheels is 9 feet and the height of the rear wheels is 4.5 feet.Its barrel is braced by a 24 feet long shaft. The barrel of the cannon is carved with flowers, animals and birds. The charge required to fire the cannon was 100 kg of gunpowder and a cannon ball weighing 50 kg.
Dhoomvan was also cast at Jaigarh Foundry in 1622. Nahar Mukhi was also cast at Jaigarh in 1675. Karak Bijli was one of the earliest cannons to be cast at Jaigarh. A flat trajectory cannon it is light in comparison to the other cannons.