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Build Diary entries for November 2010

Here are the diary entries for this month. You can use the forward and backward links to see the next or previous months. Most photos taken before 2018 are small size. From 2018 onwards, most photos you see below will have a link to a full size image by clicking on the photo.

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Machined Bolts
  There are hundreds, and hundreds of fastenings on a locomotive, rivets, bolts, studs, and screws. Even a B.R. Standard which has a fair amount of welded fabrication in place of rivets, and bolts. Although there are a majority of standard stock Whitworth bolts there are also plenty of big bolts unique to their specific task, such as the many fitted bolts.

These must be machined to an exact interference fit, a tolerance of 3 or 4 thousands of an inch oversize. Fitted bolts have to be hard driven, that's hit home with a heavy sledge hammer. If the machining is not completed correctly the bolt will either go in too easily or not go in at all. Once in the bolts are in pretty well, 'in for good'. The smaller items in the picture, bottom right, are the grease nipples for the horn guides. All these components were expertly made for us by Forrest Precision Engineering.