Kozo K27 Cylinders

I
happened to find an ad on the
auction site listing a matched set of 2 3/8 diameter bars that already
had a 1" hole through them.
This saved quite a bit on cost and
machining time. The first cylinder has been machined to size with a
1.338" bore and just under 3" long. September 9, 2019.

The pair of cylinders have been
completed with the flats machined to support the steam chest and steam
passage. September 14, 2019.

The first steam chest with all of the
lathe work completed. A series of 5 internal grooves had to be machined
in this piece which is about 2" in diameter and over 3" long. The outer
diameter will need a couple of flats milled into it like was done with
the cylinders. September 17, 2019.

The lathe work for both of the steam
chests has been completed. September 21, 2019.

This shot shows how the steam chests
fit into the flats that were milled on the top sides of the cylinders.
September 21, 2019.

The flats have been milled into the
steam chests to all them to mate up with the cylinders at the correct
angle. This view is the side that will face the locomotive and a steam
passage block will fit into the visible flats. September 28, 2019.

Four brass end plates have been
stacked and bolted together so that they can all be bored for the
cylinders and steam chests at the same times. The three holes will be
used to attach them to the faceplate on the lathe at various stages of
the machining. The steel plate will be used as a spacer between the
brass and the faceplate during boring of the hole for the cylinders. A
second spacer will be required for the boring of the hole for the steam
chests. October 5, 2019.

The end plates have been bored for the
cylinders and steam chests as a matched set. Two 30 degree angles have
been machined which will be used to orient the cylinder assembly during
further machining operations. The next step will be machining the steam
passage blocks before soldering the assemblies together. October 20,
2019.

The cylinder assemblies have been
temporarily assembled to check the fit. The next piece will be the
steam passage block that will fit into the V seen on the backside of
the assembly on the right. November 10, 2019.

The steam passage blocks have been cut
to their rough shape with two angles on each block. One of the blocks
has been inserted behind the cylinder and steam chest for a test fit.
There will be more angles to cut and a slot before the pieces are
soldered together. November 25, 2019.

The slots and angles have been cut in
the steam passage blocks and a test fit is shown at left. On the right
the V in the cylinder assembly can be seen where the steam passage
block will sit. The next step will be to solder all of the pieces
together. November 26, 2019.

The cylinder assemblies with outward
canting valves has been assembled with brass screws to hold everything
into position while soldering. Note that a temporary steel spacer bar
is used on the front side and the back side has screws directly into
the steam passage blocks. November 27, 2019.

The cylinder assemblies have been
soldered together and the back sides trued up to accept the back
plates. The back plates below will be attached with two screws and then
soldered to provide the mounting surface to the frame. Dec 1, 2019.

The back plates have been soldered on
and trimmed to the final size. The next step will be drilling all of
the steam passage holes at some awkward angles. December 8, 2019.

The backplates have been drilled and
tapped for frame mounting and for the exhaust T-pipe. There is still a
lot of shaping, steam passage and fittings drilling to be completed but
it was good to see them mounted! December 14, 2019.

The last few steps of this portion
included the drilling of the steam inlet hole and milling the
30 degree angle at the top of the end plates as seen on the assembly to
the left. next was milling and drilling the water drain holes at each
end of the cylinder where the cylinder cocks will be mounted as seen at
the bottom of the assembly on the right. December 27, 2019.