My God did I learn a ton this last few days. This part might not look like much but it is the culmination of a vast increase in my understanding of these machines.
This piece is within 0.0002" of parallel top to bottom. I doubt I'll ever get that lucky again. Lol!
I was having some flex in the head that I did not completely understand. When I reversed the direction of cut the flex in the head gave me 0.0005" of deflection in the cut that I could measure. This was after working through the x, y, and z to tighten things up and locking all axis on each cut. It wasn't until later that my machinist friend told me this not out of the ordinary on these mills.
On this piece I ran all three cuts in the same direction and just rapided back each time. Zero deflection that I can measure.
I ran this side on my fly cutter and got within 0.0002" in about 8 measurements. Zero detectable dish in the middle.
Life is not about chasing tenths on a mill and I seriously doubt I'll ever send the time on a paying job or home project to try and get this level of perfection. I even had to clean and stone my old Kurt to get the part to sit flat enough to get close to this.
I can say that I am phenomenally pleased that the accuracy is better than I will need for the stuff I do.
Right now my X is just a bit tighter than it has to be for the accuracy I require. I do not want to squeeze out the oil so I'll just barely loosen the X gib to avoid excessive wear. The Z will stay relatively snug to avoid shifting as the weight shifts. I'll just oil the crap out of it as I use the knee a ton.