Note: Distance away from mark is lost motion in machine, estimate machine distance (see discussion above). A typical machine has less than .003 inch of lost motion. As the lost motion increases, machine oscillations increase, surface finish is worsened and accuracy is reduced. Typical reasons for sudden increase in backlash is that the ball screw thrust bearing has loosened or the screw nut has loosened from the slide. Ball screw nut or gearing backlash adjustment may be required.
Check for crabbing of axis. Mount two dial indicators as far apart as possible on axis to measure travel.
Set system up for .001" jog move at 5 IPM.
Move table to indicators.
Zero both indicators.
Jog onto indicators while watching both indicators.
Check that both indicators move at the same time, and same amount.
Move .005" on (or until both indicators move a minimum of .002") then move back while watching indicators.
If machine is crabbing (both sides not moving at the same time) the usual cause is loose gibbs.
Check for loose head bracket. Put machine in trace on flat surface, square to the axis.
Turn drives off.
CAT I: Look at the PI, DI, FE, VI screen.
CAT II: Look at the deflection indicator at the top of the screen.
Push on bottom middle of tracing head (bottom of large diameter).
INCON Systems' specification states that 100 pounds pressure at base of probe body should not move probe more than .001 inch.
Make sure probe slides are locked.
Make sure probe is tight in mounting bracket.
Generally, the further 'out' the tracing head is mounted on the bracket and/or the further 'down' the tracing head is positioned, the more unstable the machine will become. If the tracing head must be 'out or down', lowering the sensitivity and cutting at a slower feed rate may be the only way to overcome this problem. CAT I: SENSITIVITY can be adjusted on the COPY SETUP screen.
CAT II: SENSITIVITY can be adjusted on the DUPLICATOR CONTROL/DUP SETUP screen. Adjust AUTO TRACE SENSITIVITY for automatic modes.
Adjust MANL TRACE SENSITIVITY for pencil trace modes.
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CAT I
