This section aims to tell the story of building a modern steam locomotive. You can read the build diary by following this link. The Build Diary provides a month by month account of the building of Hengist.
1. Frame Assembly
Virtually all of the components to build assemble the frames have now been manufactured and machined, they are in store at CTL Seal's premises in Sheffield. An order has been placed on CTL Seal to assemble the frames. We have spent a lot of time in machining the cast steel frame stretchers. These stretchers differ from those of the first 10 Clans which were fitted with fabricated stretchers. This was a lot 242 modification which followed the change for 71000 Duke of Gloucester which had cast steel stretchers in an attempt to avoid frame cracking in the area of the hornguides. Frame assembly has now commenced; all of the inter-frame components will be loose bolted to the frame plates. The frame will then be accurately aligned and checked. This is a critical task which will ensure maximum reliability in the future. Once alignment is complete, bolting will commence which will use fitted bolts. We think this will be a better solution than riveting. A number of fitted bolts will be installed to "lock" the alignment in place. After this, the frames will be inverted and taken to the machine shop where the axlebox hornguides and the frame keeps will be machined on a large machine system at CTL Seal. After this is complete, the frames will be inverted again and returned to the assembly shop. The remaining components will be fitted (motion brackets, slidebar brackets, rear frame extensions and buffer beam). All fitted bolts will be installed and the buffer beam will be riveted in place.
2. Main Cylinders
The manufacture of the pattern and the casting of the main cylinders is a long term job and we reckon that it will take 4 to 5 years to manufacture the complex pattern. Work is well underway on this job and you can follow progress by clicking the link below. All CAD design work is complete and the motion cylinder pattern is complete. Work is in progress on the valve cylinder. We have a sponsor for the casting of the cylinders.
3. Front Bogie
The design team are working on the front bogie. We have all the drawings and have built the CAD model for the main front bogie casting. A number of components are in stock and orders have been placed for some components. The major challenge is the bogie axle cannon boxes where we are currently creating CAD models so that quotations can be obtained. You can sponsor bogie components by visiting the Donate > Bogie page.
4. Trailing Truck or Pony Truck
The next task in the build plan will be to manufacture the trailing truck. With the front bogie and trailing truck fitted to the frames, we have the ability to more easily move the frames, if required.
The tender can be developed in parallel with the locomotive so we are looking at policy decisions for the tender. You can see some of our thoughts by following the link below.
The boiler is a long lead item and we already have had discussions with potential suppliers. There will be restrictions on the type of arsenical copper, traditionally used in locomotive fireboxes. There are alternative types of copper that could be used or we could follow Bullleid's lead with a steel firebox. There is an issue with steel fireboxes in that steel has only 30% of the heat conductivity of copper. Whatever we do, there is a considerable amount of design work required before we can consider placing an order for manufacture.
Below, you can find links to more detailed information on particular components or issues. We hope you find them interesting! Please click on the links below to view the articles.
Exhaust Steam Spider
Pony or Trailing Truck