Kozo K27 Rear Frame Extension

The blanks for the rear frame extensions have been fabricated and will be machined together just like the main frame. July 16, 2017

The key on the front edge of the extension slides into the groove that was machined into the tail of the main frame. July 16, 2017.

Some initial machining has been completed on the rear frame extension set. The horizontal slot marks the top of the trailing wheel opening. With the width marked by the grooves on the bottom. The top of the frame rail has been machined to the final profile. Next will be openings for the spring rigging. Followed by cutting out the wheel opening. July 23, 2017.

The oval opening at the front of the frame extension was machined by cutting two arcs on the rotary table and then cutting the excess material between the two arcs. This opening will accommodate some of the spring rigging. July 29, 2017.

The rear frame extensions have most of the major machining done now. The next step will be to finish cutting out the trailing wheel opening now that the binder caps have been made. The tab at the lower right will also be cut away since it is just there to provide an alignment screw to machine the two extensions as a pair. At the upper left is another alignment screw were a notch will be cut. August 5, 2017.

The trailing truck opening has been cut out and machined to the final dimensions. The caps are in place but still need a couple of mounting holes drilled and tapped. There are a few mounting holes to be drilled but the major machining has been completed except for cutting off the tab dangling down at the front. Aug 6, 2017.

The 14 mounting holes for attaching each rear extension have been drilled and tapped. The trailing truck transom block has also been machined and fitted between the frame rails to provide the spacing behind the fourth driver. The length of the assembly is now at 38" from rear of frame to front of the lead truck. Aug 13, 2017.

The rear beam has been machined and the frame extensions have been notched to allow the beam to be fitted. The rear frame extension have also had the various mounting holes drilled. August 21, 2017.

These are the rear boiler supports that will sit on top of the frame rail behind driver number four. The height of these will be machined down to adjust the rear boiler height to the proper level much later in the build process. September 24, 2017.

The drawbar packet, shown here upside down, mounts to the rear beam of the engine. October 1, 2017.