23rd February 2021

smart

Having completed the assembly of the extension frames and cylinders with all the bolts fitted and tightened down the opportunity was taken to try the pony truck in position to confirm clearances would allow truck to swing adequately. Although the extension frames were thicker their profiles should have been unchanged but the lower bends at the front of the cylinders were more generous than desired. The photo shows this bend on LH frame highlighted to show lack of clearance from pony truck (light green).

The spare metal was removed by hand grinding both LH and RH frames to the required shape.

210219 image007 (3) Ext.frame upside down

The next step was to try the complete extension frame assembly (which was still upside down) in position in the main frames. Using the shop overhead crane it was first lifted over to a clear section of the shop floor :-

210219 image006 (3) Ext.frame lifted top

With care it was lowered down to the floor resting on the back of the extension frames :-

210219 image004 (3) Ext. + main frame RHS
210219 image003 (3) Ext. + main frame LHS

These photos show the top of the smokebox saddle and the cylinders. By care in lowering and moving the crane away from the camera the whole assembly was slowly turned over to rest on the bottom of the cylinders on the floor. This allowed the crane slings to be adjusted for the next lift.

The second photo shows the assembly having been lowered into position within 4561’s main frames.

210219 image002 (3) Ext.frames + s'box 1
210219 image001 (3) Ext.frames + s'box 2

Nuts and bolts through the main and extension frames behind the cylinders and a frame stand to support the front of the frames enabled the assembly to be levelled and the crane slings removed. To judge appearances the opportunity was then taken to put 4561’s smokebox on its saddle.