Specialized Concentrated Focused
Machine Tool Debugging
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feed rate is 4800mm/min) can be taken into consideration; for users who are not very critical of the
accuracy, pulse equivalent can be set a litter larger, such as 0.002mm/p (the corresponding
maximum feed rate is 19200mm/min) or 0.005mm/p (the corresponding max. feed rate is
48000mm/min). For a two-phase stepping motor, the computational method of pulse equivalent is
as right: pulse equivalent =screw pitch ÷ subdivision value ÷ 200.
8) Move the machine tool manually to make sure the correctness of moving direction of each axis.
Note that NcStudio adopts
“right hand” coordinate system. For X-axis, right movement is the
positive direction; for Z-axis, upward movement the positive direction; while the positive direction
of Y-axis is to move away from the operator (if the movement of Y-axis is the movement of
worktable, its positive direction is the worktable moving towards the operator). If the direction is
not correct, alter the axis direction in the system parameters or the relative parameters of servo
driver. If Z-axis has brake, check the relative wiring of brake and the relative parameters of servo
driver before Z-axis starts to move for the first time. After confirmation, move Z-axis in jog mode,
and observe the response of Z-axis, making sure the brake can be opened normally.
9) Examine whether the value of electronic gear matches with that of pulse equivalent. Make a mark
on any axis of the machine tool and set this marked point as the workpiece zero. Drive this
marked axis to move a fixed distance by direct command input, jog or handwheel, and so on.
Measure the actual moving distance with a vernier caliper and check whether the result is equal to
the distance showed in the software.
10) Set the worktable stroke in the manufacturer parameters according to the actual size of the
machine tool to enable software limit function. The password of manufacturer parameter is
“ncstudio”.
11)
Set “Back to Machine Zero” parameter in manufacturer parameters according to the installation
position of home switches of the
three axes. After correct setting, perform the “Back to Machine
Zero
” function under the menu “Operate”. At first, home a single axis. Home the other two axes on
condition that the moving direction of the first axis is correct; otherwise, stop homing and revise
“The Direction of Backing to Machine Zero” parameter in manufacturer parameters until all axes
can return to the machine zero.
12) Start-up speed: it means the maximum start-up speed of a stepping motor from
“0” speed without
acceleration. Reasonable parameter setting will greatly improve machining efficiency and can
avoid low-speed stage of poor motion feature of a stepping motor. But if the parameter is set too
large, the machine tool may be stagnated. Therefore, the parameter setting should be feasible.
Usually, start-up frequency parameter is included in ex-factory parameters of motor, but this value
may be changed after the assembly of the machine tool; normally it will decrease, especially when
the machine tool runs with load. All in all, you‟d better refer to the default motor parameters and
your actual measurement before setting this parameter.
13) Axial acceleration: it is used to describe the acceleration / deceleration ability of a single axis, in
mm/s
2
. The value is determined by the physical characteristic of the machine tool, such as quality
of movement part, torque, resistance, cutting load of feed-motor, and so on. The larger the value
is, the less time spent in the process of acceleration / deceleration will be, and the higher the
efficiency will be. Generally, for a stepping motor system, the value is between 100 and 500; for a
servo motor system, the value is between 400 and 1200. Set the value smaller at the beginning;
