Building the Stuart boiler feed pump part 4

Now that the steam chest was attached to the cylinder the next job was to square the ends up. I used a super glue mandrel to hold the assembly.

because the valve spindle on one end it is only possible to turn the cylinder on the mandrel the cylinder was a few thousands over length so I was able to bring it to size using the steam chest as a gauge. With luck it will produce a steam tight joint, time will tell.

As can be seen in the picture above the cylinder is slightly longer thanthe valve chest. The difference was calculated and the cylinder reduced in length. Had he valve chest been to long then I could have held it in the 4 jaw centered on the valve spigot and turned off the excess. It is very important that the two parts are as close in length as possible there is only a thin gasket between the cylinder, valve chest and the end cover or base.

Bringing the outer end to size.

The castings supplied are very close to size and I ended up about 0.020" under size. I reasoned that it was better to have everything square and steam tight rather than stick rigorously to dimensions. It worth stating that any change will impact on valve travel and timing so it is worth trying to get as close as possible to the drawing.