Wasn't going to say anything, but had to chip in...
Before doing all of this is is a good idea to make sure your machine is precision leveled. More importantly that there is no twist or bow in it. This can affect your center height and straightness readings. Check left right top bottom in both directions with your level sitting on the top of the turret. Once you are sure it's straight with now bow or twist, I then normally check the slot in the turret while jogging the X up and down. It should be parallel with x movement. If not, loosen face bolts on turret and adjust rotationally. Once parallel, then shim as described in previous posts. (I too suggest leaving out the taper pins) next, onto the Z axis. Check the turret face with an indicator as you move Z. It should be parallel with Z. If not, loosen the 6 bolts holding it down (see maint. manual or parts book) and straighten it out. One final thing on the turret - centerline. Indicate the center of a boring bar holder with a co-axial indicator. Don't worry so much about the y direction since the machine has an eccentric bolt that can move the holder up and down on the face. Besides you've already done this by checking the turret slot for parallelism with X. Find the X center and Calculate zero in your zero offset page. Write this new number down in the data management card in the back of your machine so if someone changes it, you can go back to it.
Next headstock. I think there's at least 6 bolts holding it down. I like to use a brass or aluminum bar. Skim cut it about 1 foot and check for taper with a Micrometer. Use a dial indicator when moving the headstock to see how much you are moving it. Repeat until she's straight. Okuma usually considers it straight when it is below .0005/4" on X and .0005/12" on Z. Always shoot for better, you can hit it without fail even on beat up machines.
Getting tired yet? Last but not least you may want to indicate your chuck in too to make sure there's no runout. Runout caused balance issues and can cause runout in your parts even if it's only a few thousanths.
Good luck - I don't think you'll be bored for the day...!  |