Carpenter Oak & Woodland was selected for these projects because of our proven track record in timber engineering – and our market-leading knowledge of how large timber structures perform.

Few projects which we have undertaken have been as unusual, or as demanding, as the construction of several timber war machines.

All based on ancient designs, the war machines had to be as authentic as possible – and work properly, once complete. Although we worked to original specifications, power tools were used to save time and cost; for the same reasons, the timber was converted from the round log to square timbers at the saw mill. With the exception of these processes, the war machines were built by hand, using traditional methods.

Trebuchet, Secrets of Lost Empires, Channel 4

Our first war machine was a trebuchet – a medieval siege machine – for Channel 4, built for a competition between two different siege machines. The trebuchet is a massive structure with a 49-foot throwing arm, capable of throwing a 300-pound boulder around 20 yards – at speeds of over 120mph! You can read a detailed account of the construction and use of this trebuchet on the Timber Framers’ Guild Web site.

Ballista, Building the Impossible, BBC and The Discovery Channel

Built with Expedition Engineering for BBC TV and The Discovery Channel, the ballista was a faithful replica of a Roman catapult, described in ancient texts from around 25BC. When built, the ballista was able to fire a 26-kilogram limestone ball around 100 yards. A highly powerful machine, it had a spring tension of up to 200 tonnes per spring – and was capable of quickly laying waste to enemy fortresses. You can find out more about this project by downloading this PDF (499KB).

The ballista from Building the Impossible

Trebuchet, Warwick Castle

For Warwick Castle, we built the world’s largest working trebuchet – a mighty war machine which stands 18 metres tall and weighs 22 tonnes. The design of the trebuchet was based on notes and drawings from the 13th century. The trebuchet is made from oak – apart from its throwing arm, which uses the more flexible ash. The trebuchet comprises over 300 different parts, all held together with metal fixings. It can throw a projectile over 300 metres and needs a team of 8 men, working for half an hour, just to prepare and load the machine.

The world’s largest trebuchet at Warwick Castle

Leonardo’s Crossbow, Leonardo’s Dream Machines, Channel 4

For Channel 4, we constructed a replica of a war machine, designed 500 years ago – and never built – by the great Leonardo da Vinci. This giant crossbow, with arms almost 80 feet across, was built to da Vinci’s exact scale and specification. Da Vinci wanted to solve the problem of accuracy found in cannons – because, although cannons are effective, their massive recoil seriously affects their precision. The catapult would not recoil – and could therefore hit the same target, time and time again.

Leonardo’s Crossbow from Channel 4’s Leonardo’s Dream Machines