Kozo K27 Cylinders



This is the start of the second part of the cylinder assembly construction. The holes have been drilled and tapped for the cylinder and steam chest covers as seen on the left. The right shot shows the two sight holes at the top, the snifting valve and lube holes in the middle and the steam inlet hole from the prior section at the bottom. Next will be the drilling of the exhaust passages which will require an interesting setup on the milling table. January 3, 2020.


Today was spent drilling the exhaust passages that run from the outside grove of the steam chest to the center of the backplate. This involved mounting the assembly rotated 36 degrees on a 90 degree angle plate to orient the piece for drilling. One of the more complicated steps in the machining of the cylinders. January 4, 2020.


Here is the view of the exhaust passage from the backplate side of the assembly. There is a second exhaust passage heading out to the other end of the steam chest. These passages will run through a T-pipe between the frame rails and then up through the bottom of the smoke box to exit at the stack. Next up will be another set of passages that will require a slightly easier setup for machining. January 4, 2020.


The project today was cutting various angles on the end plates. This will assist with drilling the steam passages between the steam chest and the cylinder and also brings the end plates closer to the final shape. The steam inlet, snifting valve hole and lube holes are visible at the top. The drain hole for the cylinder drain cock can be seen at the bottom. January 5, 2020.


The operation today was to drill the steam passages between the cylinder and the steam chest. This was performed with the cylinder assembly rotated 37 degrees on while mounted on a 90 degree angle plate. One assembly has been completed and the second still needs to be drilled. January 12, 2020.


The steam passages have been drilled at the ends of both cylinders. A rotary tool was used to round all of the edges inside the cylinders to prevent the O-rings from being cut as they are installed. January 20, 2020.


One of the end plates has been rounded and angles cut to the final profile. Only three more end plates to trim up. January 20, 2020.


Both assemblies now have the end plates finished to the final shape. Next I'll be working on the caps for the steam chests. February 8, 2020.


The front heads for the steam chests have been completed and the front outer covers are also done. February 15, 2020.


The outer covers for the back of the steam chests are completed. Work has started on the steam chest back heads which are fairly complicated due to having the support for some of the valve gear. February 16, 2020.


The lathe work for one of the steam chest backheads has been completed and milling has been started. Another flat will need to be cut on the bottom side and then some angle cuts to taper from the large end to the flats. Then there will be some hole drilling for the mounting holes and covers. February 17, 2020.