Frames – the main activity in early 2003 was the fitting of the Cartazzi hornblocks and hornstays. A great amount of adjustment and re-adjustment was required to ensure the necessary clearances were adhered to. It became apparent the the LNER had modified the working of the Cartazzi slides when the A1s were in service but these changes had not been recorded on the original drawings. In consequence the Trust opted to increase the nominal clearance of the axleboxes in the hornblocks from 0.025″ to 0.050″ . By the autumn the footplating down the sides of the locomotive had been made and fitted.
The Cartazzi slide with roller bearing fitted
Wheelsets – with their tyres now fitted and turned the driving wheels were taken to North View Engineering in Darlington to have their crankpins finished. Having had the hornblocks welded in position the bogie wheelsets could be trial fitted. The cannon boxes and axleboxes for the coupled and bogie wheels had finally been fitted with their bearings and should now remain in place until the loco’s first overhaul.
Motion – Hawk Fasteners supplied over £1000 worth of bolts, slotted nuts and washers to fit the slidebars which were now ready for final erection, a process completed by the end of the year. The crossheads were white-metalled and had the oilways milled and drilled at North View. The remaining valve gear forgings had been delivered for machining and Ufone completed the inside connecting rod and strap.
The fully machined coupling and connecting rods
Cylinders and valves – Ufone machined all six valvechest liners and the front steamchest covers were machined by North View and delivered to the works. Meanwhile A1 Trust volunteers were making good progress producing the cylinder draincocks.