Part 10: Putting it back together—May 2001
Rivetting bogie frames
Perhaps the title Putting it back together is a little early yet, but progress has started in the right direction. At one of the regular volunteer nights recently, the frame for one of the tender bogies, which had been partially dismantled for straightening, was drilled ready for rivetting back together.
After the holes had been drilled, the noisy and dirty task of inserting and squeezing hot rivets began. The rivet is heated to white-heat in a forge, inserted in the hole, then with some teamwork, squeezed in to hold the two plates tight together.
One person holds a "dolly", which is not a child's toy! It is a large, heavy steel block, which is held against the rivet head, to stop the rivet falling out, and hold the head hard against the plate.
The other person operates an air-powered impact gun, which gradually compresses the "blank" end of the rivet into the hole and countersink in the other plate.
The rivets we're using here are about 7/8 inch (22mm) diameter, and require about 10 seconds of impacting before they are "cold". By cold, we mean that it is no longer red-hot, and has begun to harden and shrink in its hole. This shrinking puts the greatest squeeze on the plates being held together.