PM Research #5 - how do I bore the main crankshaft journals?

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Hi Nz120, I'm curious as to why you are using a rotary table ?
Baron

I set up the rotary table to allow me to rotate to a 45 degree angle for the valve slide recess to be milled. I squared up the casting using a dial gauge along the flat of milled face of the valve guides on the casting and then rotated.
When I do the second kit I am thinking to mill square faces to the base of the frame casting so that I have true faces against which to make it simple to mount and remount - i.e. If I had done this then I could easily set at 45 degrees onto the bed of the mill.

Being self-taught, the "obvious" solution to any problem is
not always obvious to me haha
 
20200516_154649.jpg

using the rotary table for milling of the valve guide, and the clearance slots for access to the main journal cap screws.
 
Almost the same story as yours. Started 10 years or so ago, second marriage, kids, other hobbies. Finished building mine this weekend. It’s a great runner, ticks over on about 3 lbs of air after breaking it in on 6 lbs for 30 min. still need to get a nice coat of paint on it.
When I started mine I milled the bottom flat, then the crank journals and valve guides. All other operations used those as a reference.
 
Almost the same story as yours. Started 10 years or so ago, second marriage, kids, other hobbies. Finished building mine this weekend. It’s a great runner, ticks over on about 3 lbs of air after breaking it in on 6 lbs for 30 min. still need to get a nice coat of paint on it.
When I started mine I milled the bottom flat, then the crank journals and valve guides. All other operations used those as a reference.
thanks for the encouragement....I am enjoying getting back into it....Covid-19 has given me more time..if only someone would pay me to partake in my hobbies haha
 

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