I started by milling the base to just about the required dimension.  Finish milling will be done later, when everything is to be aligned.
After the base was milled, the clyinder was rotated 180 degrees, and a  parallel was used in the bottom of the vise. This would allow milling the top of the water hopper parallel with the base, which  would make it a little easier to align in the 4-jaw later.
I faced one end, removed the cylinder from the 4-jaw, repositioned it, , and then faced the other end.  After both ends were faced, the cylinder was removed again, marked out, punched and returned to the 4-jaw.  The indicator and center finder allow positioning where the hole for the liner will be bored.
The liner hole has been bored, Here the inner recess for the water jacket around the liner is being bored, using a special boring tool.
First a boring bar was used to open up the water hopper
I then drilled a 1/8 inch hole in each corner
A 1/8 inch end mill was then used to square out the hopper.
(Only broke one endmill ! )
THIS PAGE COVERS  MACHINING THE CYLINDER..
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