I thought it would be worth putting together a short time line of the cylinder production for interest. starting with the original set and finishing with the castings as delivered to Sheffield Park last Friday.
As you can probably see in the picture above, the original cylinders were in such a state there really was no other option other than to replace them. you may be able to just make out a perforation in the exhaust steam passage towards the centre top of the block.
Matt Holloway took on the job of researching the original Ashford drawings for the cylinders and converting them to CAD and going onto producing a 3D CAD model which can be seen above.
From the CAD model we decided to have a 3D print manufactured. This was done partly for reference to see what they would look like as a tangible piece of material. A by product of this was that we have a model to display on our sales and information stands.
From the CAD information a set of polystyrene patterns were manufactured this was done using a computer controlled robot with a rotary file attached. A by-product of this was a quantity of fake snow!
The castings were removed from the sand moulds and fettling took place to remove the runners and risers and vents that had been put into allow the gasses to be dissipated as the polystyrene burns off as the molten iron is poured in.
once the castings were cold they were put on a palate and shrink wrapped for delivery. They can be seen in the yard at Sheffield Park following delivery.
|The Cylinders unwrapped!|
The cylinders were unwrapped to allow seasoning to start to take place. This allowed us to see the quality of the castings.
The next step is to season the castings, either by leaving it so that the stresses are relieved naturally over a period of time, or by heat treating.
Once the seasoning has taken place machining can start
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