During production of the recent Tim Burton directed Charlie and The Chocolate Factory film staring Johnny Depp, the special effects engineers at Pinewood Studios contacted their local WYKO branch in Slough to help with a major challenge; how to pull a 6 tonne boat nearly 300ft through a winding chocolate river, while keeping the journey smooth and safe for the occupants. The solution was provided through collaboration with Renold Chain using large pitch roller chain and a sprocket drive system. The chain was manufactured in the UK and supplied complete with a variable speed drive system to allow smooth gradual acceleration and consistent speed/torque performance. The chain drive proved doubly useful since the scene required the boat to be moved through the river and returned to the start many times to perfect the shot before the live take, the chain drive enabled the set engineers to simply reverse the motion in order to return the boat to its starting position instead of having to push it back by hand.