[mikeymgs]

THE BORES ID ARE OUT 0.0018 OUT OF ROUND THE OD TURN IS RIGHT ON IT SEEMS THE FASTER THE SPEED WITH THE FEED THE BORES GO OUT MORE AS IN 0.003. THIS IS WHAT I SEE 600 RPM =0.0002 . 1100 RPM = 0.0004 . 1600 RPM = 0.0018 . THE SPINDEL WAS REBUILT LAST YEAR. IT HAS NO PLAY. THE FINISH IS A 14 TO 22 . WERE ARE USEING THREE JAW CHUCK TO CHUCK THE PARTS AND THIS ALSO HAPPENS ON THE 2 JAW CHUCK TO. THE BELTS ARE SNUG, THE X AXES LOOKS TO BE GOOD WITH NO BACKLASH. BORES OUT OF ROUND, FINISH GREAT, OD IS RIGHT ON. SPEEDS AND FEEDS RIGHT ON, DONT NO CAN ANYBODY HELP ???:drowning:

[nautomation]

put a dial and see the all axis in respect to spindle , and confirm for specific comment on troubleshooting

[mikeymgs]

z axes has 0.0002 back lash and x has 1 to 2 back lash, the turret is in aliginment radially and linear .:drowning: i hope this helps

[underthetire]

Running bar stock?

[mikeymgs]

castings, the ID out of round gets worse when the spindel speed go's up. but the OD stays good with no out of round condition ???? the castings are smooth. they run with no vibraytion. it's a singel point boring bar.

[underthetire]

Well, the only way your going to get out of round is the part moving or the spindle running out (assuming good castings with no hard spots). Being castings, I'm betting an either part moving, or possibly your crushing them. Kinda hard to diagnose from your details.

It is possible you have a loose rear spindle bearing, and once you stick a boring bar in the part, it's putting difference forces causing the spindle to move around.

[mikeymgs]

THANKS I WILL LOOK AT THE REAR BEARING. I HAVE TO WAIT TILL MACHINE IS OPEN TO CHECK OUT. THANKS