- Begin with the guide channel closed and the bar pusher one foot forward from the rearmost position from the lathe.
- Press and hold the [Pre Auto] button (top right button) on the remote control.
- After approximately 10 seconds the bar pusher will begin to move to the rear toward the home position micro-switch.
- Release the button as soon as the pusher begins to move rearward.
The remnant length is controlled by the parameters:
- “Maximum Pusher Forward Travel” (Also referred to as ‘front limit position.’)
- “Part Length + Cutoff Tool Width”
- The distance from the chuck or guide bushing the cut-off occurs.
- Length of the material in the guide channel.
The front limit position is the farthest the bar pusher can travel forward into the lathe. The part length is the sum of the overall part length, the width of the cut-off tool and the amount of material left for facing.
When the pusher doesn’t have enough travel left to move the distance in the part length parameter before reaching the front limit position the [End of Bar] signal is sent.
If the remnant is too long verify the front limit position parameter and the part length parameter. Keep in mind that on all lathes there will be a certain amount of unusable material. This unusable length can be measured by moving the bar pusher as far as possible into the lathe and and measuring from the cut-off tool to the inside of the bar feeder collet stop.
For Swiss type lathes move the headstock to the cut-off position and measure from the back of the cut-off tool to the stop inside the bar feeder collet. This measurement is your minimum remnant length. The remnant length can be up to one part length longer than the minimum depending on home much material is remaining.
- Before beginning, reference (re-zero) the bar pusher.
- For sliding headstock machines only, move the headstock into overtravel toward the guide bushing.
- For all machines, move the bar pusher with a collet attached, no material in the channel, forward until the bar pusher collet contacts the lathe collet. Smaller diameter bar pushers may travel inside the lathe collet, larger diameter bar pushers may stop sooner at the back of the collet or at the collet sleeve.
- Record the position of the bar pusher from the bar feeder screen.
- Enter the position minus 3mm (1/8 inch) in the [Maximum Pusher Forward Travel] parameter in the [F2 Fixed Parameter] section. [Please note that if the guide channel size is changed the bar pusher of the new channel may have a different stopping point in the spindle than the bar pusher originally used to set up the machine.]
The facing position controls where the new bar stops in the lathe during a bar change.
For Swiss type lathes:
- The value of the parameter is a measurement of the distance from the facing flag to the face of the guide bushing minus 2 inches.
For fixed headstock lathes:
- Measure the distance from the facing flag to the face of the collet.
- Enter the measurement in the [Facing Position] parameter in the [F2 Fixed Parameter] section.
- To get to this parameter press the [F2] button and enter the password 258.
- The screen will change to show the Facing Position parameter.
- Type the new value and press [Enter] (F9 key to the right of the 0 key).
- Press the [F3] key to return to the main screen.
The most common cause for losing the bar from the pusher collet is the lack of a dwell or too small a dwell in the part program after the lathe collet opens and after the lathe collet closes.
The dwell is required to allow time for the signal from the lathe to reach the bar feeder and for the bar feeder to act on the signal.
Looseness in the linkage of the sync device, a worn rotating tip, obstructions to the bar pusher in the channel or nose and slack in the synchronization belt or drive belt can also contribute to losing the stock from the pusher collet.
Check the synchronization device:
- Load a bar into the lathe collet as normal.
- With the bar feeder in manual and the lathe collet open, disconnect the synchronization bar from the lathe and push the bar toward the bar feeder to make a gap.
- Close the lathe collet to engage the synchronization.
- Pull the synchronization bar toward the lathe.
- If the synchronization device is working properly you will not be able to move the sync bar toward the lathe. Do not push the sync bar toward the bar feeder. If the synchronization is working this will pull the bar pusher collet off the material.
When changing to a new job, changes in parameters should be made to the [Part Length + Cutoff Tool Width] parameter of the [F1 User].
The proper setting is the sum of the overall part length + the width of the cut-off tool + any facing stock used. This dimension reflects the total amount of material required to make and cut off one part.
The facing length may need to be altered in case of a left-handed cutoff tool or to provide a longer “stick-out” of material on the bar reload:
- Locate the [Facing Position] parameter located in the [F2 Fixed Parameter].
- Adjust the parameter higher or lower as needed. This parameter requires the password – 258.
The [Open Collet Speed] and [Open Collet Torque] parameters normally are not changed but can adjusted in special cases such as extremely small or large diameters or flexible material. These parameters can be found in the [F1 User] parameters.
For Swiss-type lathe applications a ½ second dwell, in the main part program, is recommended.
This comes both after the collet opens and after the collet closes to allow the signal for the lathe collet open to reach the bar feeder and be processed. This also allows time for the synchronization device to release at the collet open signal and to reengage at the closed collet signal.
For fixed headstock lathes a dwell is required in the part program to give the bar feeder time to advance the material for the next part before the collet closes.
The length of dwell is dependent on the length of the part to be feed out.
- Locate the rear plate of the bar feeder
- Loosen the two bolts in the slots on top of the beam near that rear plate.
- With the screws loose, pull the motor toward the rear plate to tighten the drive belt
- Tighten the adjusting bolts.
- Locate the idler sprocket
- Move idler towards the rear panel.
- This will cause chain to tighten.
To adjust the rollers:
- Load a bar into the lathe and close the collet.
- Push the [Pre-Auto] button (pendant control, top right button) to close the roller steady.
- The long cap screw with a sleeve and jam nut is used to adjust the rollers. Turn the screw counter-clockwise until no tension is felt on the screw.
- Press the [Manual] button (pendant control, top center button), then the [Pre Auto] button again to make sure the rollers are closed on the bar.
- Rotate the adjusting screw clockwise until tension is felt, then rotate the screw clockwise another 1/4 turn.
- Tighten the jam nut.
- Press [Manual] to release the rollers. This procedure applies to both the 1st anti-vibration roller and the MAVD rollers.
Newer versions of the Minuteman 320 moveable anti-vibration devices have the capability of using bushing blocks in place of the standard rollers. These blocks are available in three sizes: 8mm, 16mm and 22mm. Choose the blocks that are at least 1 millimeter larger than the stock to be run.