More machining fun tonight
I re-drilled the bolt circle to 4.5" to suit the Ford hubs. This meant setting up the rotary table and ensuring the rotor is centered.
I found the center point between the existing holes and drilled pilot holes then out to 1/2" and then to the final diameter of 5/8" for the shoulder on the wheel studs.
A trial fit found the center bore slightly too small. I had eyeballed it and thought it OK but the Ford center bore is actually 70.5 mm and the rotors were 70mm. Had to chuck the rotor up in the lathe again and take the center bore out by .5mm
I used the 4 jaw chuck and a dial indicator to get it exactly centered since everything is referenced off the center bore when the rotor is bolted to the hub.
Hooray! Perfect fit.
The caliper bolts up OK but I had to shim it out by about 2mm to compensate for the slightly larger disc diameter.
It was a really good feeling to be able to bolt a wheel on again.
Now to modify the other side rotor then sand blast and paint both of them.
Cheers