Saturday, 30 January 2016

Here are some pictures from the work done on 828 in the past few days. We removed the cracked LH Driving Hornblock from the loco and then put a heavy jack in place to give the frame some temporary support. When we inspected the frame plate we found an old repair dating back to BR days (or earlier). The frame plate has cracked in the area where the repair was made. Not a big problem - our welding contractor has looked at it and is confident that modern welding will do a proper job.. In the meantime we've confirmed that a foundry in Central Scotland can use the damaged LH Driving Hornblock to make a pattern and cast a new component in the correct grade of steel. Mr Graham King and Mr Paul Blount both have copies of the BR material specifications for ex-LMS locomotives and the foundry will be able to identify the appropriate current specification that aligns best with the 1940 standard quoted in the BR publication..

Sleepers placed across the pit and a heavy jack giving the frame the relief that it needs to avoid any tendency for  excessive stress at a weak point. The old repair can be seen quite clearly on the left side of the picture between two of the bolt holes.

This is the crack that we found on the frame plate underneath the LH Driving Hornblock. It extends between the two bolt holes and disappears down into the plate. The full extent will be confirmed by NDT and then it will be ground out and rewelded.

The cracked horn block being prepared for use in making a pattern. It will be returned to Aviemore with the new casting and kept as part of the "black museum". The Trust that owns 828 is committed to keeping the loco in operational condition for as long as possible. Over a long life (117 years and rising) she has had many new components but the historical link to her original 1899 condition remains intact.
The record sheet that we created to record various data during removal of the horn block. It's interesting to see that bolts in the two legs were different sizes. This is a good indication that this is not the first time the horn block has been renewed..

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