Southworth Boiler Feed Pump – progress

by John

Most of the components of the vertical Southworth pump have now been machined, and following are some photos of the assembled bits. Not a final assembly, because the gaskets are yet to be fitted. My friend Stuart is currently, or possibly has already, cut out the gaskets on his CNC laser.

I did not make the external valves on the exterior. They were mostly sourced from sales of a deceased steam model maker. In using the parts on the Southworth pump, I hope in will be seen as a compliment to that maker, acknowledging his efforts. Thanks Harry.

The vertical Southworth steam powered boiler feed pump stands 150mm/6″ high. At top is the steam cylinder, piston, steam chest and steam chest lubricator (also made by Harry C.). At bottom is the actual pump. Yet to fit the gaskets and pump valves, and to block the holes shown, which were required during machining but become permanently closed now that machining the internal cavities is complete.
Slightly different view, from above. The red handled pliers are Knipex parallel jaw pliers, which have been invaluable during this project. I have 3 sizes of these pliers, and will eventually have the full range. They are not cheap, but worth the cost.
The steam chest, with cover removed, showing the 2 valves. On the right is the pilot valve which is activated by a lever from the piston rod. On the left is the shuttle valve which is activated by steam from the pilot valve through hidden passages, and which directs steam to the main piston. Now that I have made the parts and assembled them I am getting some comprehension of how this pump actually works! This photo shows that the taper on the steam entry valve needs some tidying. The copper washers under the 2 external valves are compression types, which are very useful in positioning those valves when the threads don’t exactly finish where the maker wants.

So, that is progress to date. A few more parts to make and install. Then to make various adjustments and get the Southworth pump functioning.

Coming up later this week. A visit to The Army Museum at Bandiana, Wodonga, Victoria, to see the Armstrong 110pr (110 pounder refers to the weight of the projectile the 1861 cannon could fire) breech loading cannon barrel, which I modelled last year from drawings and photographs and 19th century book descriptions. I am hoping that original inscriptions and engravings will still be visible on the barrel so I can add them to my model. As far as I am aware, this barrel is one of only two existing examples in Australia. And of course I will be touring the rest of the museum taking photographs to post here.