Before putting the components back on the base, I took the 0.093” off the bearing pedestals to eliminate the shim under the cylinder.
I can’t help noting that the crank end bearing and frame castings both had plenty of metal whereby I could have eliminated the bearing/frame shim by making the frame just 0.078” longer. A more experienced modeler may have noticed that, but I’m not that person yet. At my age, prolly not going to happen. 😊
The base still needs some attention. The hole for the exhaust and the spotting on the bottom side for the cylinder mounting bolt heads.
The exhaust hole does not have a diameter dimension, but does indicate it is on a cylinder center line. I have the cylinder center lines’ origin as ABS 0 in the DRO, so I go back to it. On the cylinder print, the location of the exhaust hole center gives me that last dimension and I now have the location to drill.
The last item is to turn the base over and spot the cylinder mounting bolt holes.
S330-A-Base-11.jpg, S330-A-Base-12.jpg
Putting the components back on the base and having the items fit up and the shaft rotate freely gives me the feeling that the end is in sight. The last casting to machine is the flywheel. Obviously, a bunch of details are left, however it is coming along.
S330-S332-FitUp-2.jpg
Catching up on another detail. The bearings are spec’ed to be 1” wide at the crankshaft. This final milling could have been completed after the bearings were bored, but wanted to see the fit up. 😊
Each bearing was respectively remounted on the jig plate, fixed in the mill vise, and milled to spec.
S330-C-MainBrgCrankEnd-12.jpg, S330-D-MainBrgOuterEnd-9.jpg
rstreift
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