Sapper was designed and built by Jim Haylock in conjunction with Roger Marsh. The loco was envisaged as representing the War Department 4-6-0 tank engines, however it would also feature a tender.
The loco was named Sapper in honour of its military roots.
One of the most significant developments of Sapper were the use of 3½” bore, 4¼” stroke cylinders and Walschaerts valve gear.
Sapper also featured inside frames as per the loco it was representing, however this caused issues with stability and balancing of the wheels. The solution was to add significant extra weight to the inside of the frames, along with large internal balance weights on the wheelsets.
Over the years, Sapper has proved its worth not only as a mainstay at Tucktonia, but it has continued to be so at Moors Valley.
It has received a significant rebuild including a new chassis, and is currently out of service needing a boiler re-tube and a full overhaul on the bottom end.
