The Martin Baylis double acting slide valve twin engine has been designed to replicate as much as is practical at this scale the appearance of a compound engine. Great attention has been paid to represent the materials that would have been in use at the time; predominantly cast iron, brass, bronze and steel.
Items such as connecting rods and eccentric rods are fully machined and profiled giving the appearance of the original items. In the case of the eccentric rods, stainless steel and brass have been used to simulate the bronze eccentric strap and steel eccentric rod of full sized practice. Effort has also been made to incorporate into the engine items that are so often seen as separate entities. The displacement lubricator sits between the cylinders and the throttle assembly is hidden within the steam chest, giving a neat and uncluttered appearance to the engine. Steam-ways are an integral part of the cylinder block so there is no external pipe work other than that to deliver the steam and remove the exhaust.
The simulated wooden cladding complete with brass straps adds to the look of authenticity, as do the cylinder head fixings which are especially made to replicate dome head bolts. Connecting rods display bolt heads at the big ends. Reversing and throttle leavers have been designed to look in keeping with the controls of a real engine. Crank shaft webs are profiled to give the appearance of counterbalanced webs. This attention to detail in addition to the overall construction and aesthetic of the engine is designed to be pleasing to the eye.