It has been a few weeks since I reported on Samson’s progress, so here is a synopsis of recent, exciting, progress…

Below: The drain cocks fitted and with the first section of operating linkage fitted in place.  It will find its way to the footplate, probably braced against the left hand crankshaft pedestal to provide some rigidity.  Tail pipes will be directed downwards, outside of the boiler cladding and then turned to avoid depositing oily water and steam directly onto the rail head in front of the driving wheels!

Below: David has made the piston rings, and they are seen in this sequence being fitted to the piston, the piston rod also featuring in some views.  Here are the various parts laid out.

Below: Piston plus first ring.

Below: Piston plus first ring plus central spacer.

Below: Complete assembly with second ring and piston cap fitted.  The rod sits behind, note the castellated nut, which enables the piston to be secured tightly and the nut prevented from rotating loose.

Attention has also returned to the cylinder block and the manufacture of the various components for the Salter safety valve.  An additional modern spec safety valve will also be fitted towards the rear of the boiler.

Below: This view shows the gunmetal insert within the iron safety valve casting atop the cylinder block.

Block: The component on the right is the safety valve itself, which sits in the insert shown above and is held against pressure by the safety valve arm and spring. On the left are bits and pieces for the assembly, including the knurled retaining collar for the spring balance.

Below: The valve inside the insert, with the lever swung back to the top right.

Below: Two views showing the overall assembly with the Salter type spring balance to the fore (the brass tube).  This contains two springs and is anchored at the base, the upwards leverage being imparted by the steam on the valve, via the arm which is held in place by the collar.  It is simpler to see than explain!  Note the lovely square thread on the spring rod and means of enabling a small amount of swing to be incorporated – an aid to seating the safety valve when the pressure reduces (Coffee Pot and No.18 are similarly fitted with these Salter spring balances).

Below: Highlight of today was a momentous moment for Samson and its small team – the engine unit was turned over for the first time, using compressed air fed directly to the valve chest.  It ran beautifully from the start, and only small adjustments are needed.  Needless to say, David and myself are absolutely thrilled!  Here is a camera-filmed slice of the occasion: