Overview: The challenge This week's Scrapheap Challenge is a test to see who can become a champion martial mechanic by building a kung fu car. The teams will have to construct a moveable car complete with a karate-chopping device. It's gotta be tough as it'll have to axe its way through six concrete slabs, half a metre of ice and finally a huge hunk of wood. Lumbering Jacks Tree-cuttin' captain Baden and his fellow fellers Andrew and David are a top Scrapheap team. They ‘say it how it is’, love their agricultural machinery and are keen off-roaders. A jolly team with a good rapport, a sense of humour and a great attitude. With the motto 'If it’s been built before, it can be built again', this team have the potential to go far. Our forest-loving, axe-wielding men of South Wales are here to cut their opponents down to size. Robyn Rushforth is the Lumbering Jacks' expert. As an MOD-trained engineer with 16 years spent in the demolition industry, he certainly has the know-how to smash stuff up. He’s also a versatile bodger and enjoys banging together anything from rally cars to underwater ROVs. The Haggis Bashers Watersporting enthusiasts from Fife, these boys dive, water-ski and fish in their spare time. The team come from a largely agricultural background and bring a range of skills: Andrew has been in mechanics for 20 years and specialises in heavy farm machinery, Johnny knows his jet engines and Raymond is a woodwork and metalwork expert. Three different characters but all with that famous Scottish dryness, these bonny boys are guaranteed to give us more than a Highland fling! The Haggis Bashers' expert is Essex boy Richard Keall. A car mechanic turned plant fitter, he currently works for one of the country's biggest demolition companies, keeping the machines in tip-top condition. The judge When it comes to demolition, this week’s judge, David Clarke, has seen it all … well, almost! After 25 years working in demolition, he is currently president of the National Federation of Demolition Contractors.