FMB Minimag 20: Questions & Answers

How do I 'home' the bar feeder (also referred to as 'resetting the zero point')?

FMB Omron touchscreen controls:

  1. Begin with the guide channel closed and the bar pusher about one foot forward from the rearmost position from the lathe.
  2. This model bar feeder resets the home position each time the bar pusher turns on the home proximity switch. No further steps are required.

FMB Omron (pre touchscreen):

  1. Begin with the guide channel closed and the bar pusher about one foot forward from the rearmost position from the lathe.
  2. This model bar feeder resets the home position each time the bar pusher turns on the home proximity switch. No further steps are required.
How do I shorten my remnant length?

These instructions cover the following controllers:

  • FMB Omron (Touchscreen) Control
  • FMB Omron (Pre Touchscreen) Control

The remnant length is controlled by the parameters:

  1. “Front Limit Position” and “Part Length”
  2. Distance from the chuck or guide bushing the cut-off occurs.
  3. 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 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.

How do I set my 'end-of-bar' (FMB: 'front limit position')?

FMB Omron touchscreen controls:

  1. Before beginning reference (re-zero) the bar pusher.
  2. For sliding headstock machines only, move the headstock into overtravel toward the guide bushing.
  3. 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.
  4. Record the position of the bar pusher from the bar feeder screen.
  5. Enter the position minus 3mm (1/8 inch) in the [Service] parameters, [Position] page under the [Front Limit Position] parameter.
  6. To get to the [Front Limit Position] parameter:
    1. Press the “SERV” button from the [Manual] screen. The screen will change to the [Positions] parameters.
    2. Press the value for the [Front Limit Position] parameter and a keypad will appear on the screen.
  7. Type the new value and press the [Enter] button to enter the value and lock the parameters.

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.

FMB Omron (Pre touchscreen):

  1. Before beginning reference (re-zero) the bar pusher.
  2. For sliding headstock machines only, move the headstock into overtravel toward the guide bushing.
  3. 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.
  4. Record the position of the bar pusher by pressing and holding the [HLP] button while the bar feeder is in [Manual] mode.
  5. Enter the position minus 3mm (1/8 inch) in the [Service] parameters, [Position] page under the [Front Limit Position] parameter.
  6. To get to the [Front Limit Position] parameter:
    1. Press the [F6] “SERV” button from the [Manual] screen. The [Service] menu will be displayed.
    2. Press the down arrow button to scroll to the [Position Front Limit] parameter.
    3. Press the [Plus] and [Minus] (+ & -) buttons at the same time to highlight the parameter value.
  7. Type the new value and press the [Enter] key to enter the value and lock the parameters.

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. In this case the parameter should be altered to reflect the change in the maximum forward travel of the bar pusher.

How do I set the 'top cut' position (first insert position / facing length)?

FMB Omron touchscreen controls:

The first insert position controls where the new bar stops in the lathe during a bar change.

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, Swiss type lathes only) or to the face of the chuck/collet (Fixed headstock lathes).

The position can be extended further into the lathe with the [Extension of First Insert] parameter in the [Part Special Settings] menu.

  1. Measure the distance from the facing flag to the face of collet or guide bushing with a steel tape measure.
  2. Press the [SERV] button on the [Manual] screen for the [Positions] menu.
  3. Press the value you wish to change, and a keypad will appear on the screen.
  4. Type the dimension and press the [Enter] key to store the change to the parameter.

To move the bar further into the lathe, use the [Extension of First Insert] parameter.

  1. Press the [PART] button on the [Manual] screen, then press the [SPECIAL] button.
  2. Press down arrow to move to the [Extension of First Insert] parameter.
  3. Press the [Plus] and [Minus] buttons together to highlight the parameter.
  4. Type the desired value and press [Enter] to store the change and lock the parameter.

FMB Omron pre touchscreen:

The first insert position controls where the new bar stops in the lathe during a bar change.

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, Swiss type lathes only) or to the face of the chuck/collet (Fixed headstock lathes).

The position can be extended further into the lathe with the [Extension of First Insert] parameter in the [Part Special Settings] menu.

  1. Measure the distance from the facing flag to the face of collet or guide bushing with a steel tape measure.
  2. Press the [F6 SERV] button on the [Manual] screen, then press the down arrow for the [Positions] menu.
  3. Press the [Plus] and [Minus] (+ & -) buttons at the same time to unlock the parameter for editing. If the highlighted parameter is not the one needed use the up or down arrow to move to the correct parameter.
  4. Type the dimension and press the [Enter] key to store the change and lock the parameter.

To move the bar farther into the lathe, use the [Extension of First Insert] parameter.

  1. Press the F5 [Part] button, then press the right arrow button for the [Special] menu.
  2. Press down arrow to move to the [Extension of First Insert] parameter.
  3. Press the [Plus] and [Minus] buttons together to highlight the parameter.
  4. Type the desired value and press [Enter] to store the change and lock the parameter.
How do I prevent the pusher-collet assembly from disengaging with bar stock in a sliding headstock (Swiss) lathe?

All controls:

These instructions cover the following controllers:

  • FMB Omron (Touchscreen) Control
  • FMB Omron (Pre Touchscreen) Control

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.

A second cause of losing the material from the bar feeder collet is jogging the headstock when the synchronization is not engaged.

The sync will only engage if the bar feeder is:

  • In [Automatic] mode
  • [Step 17] is on
  • Lathe collet is closed.

Moving the headstock with the collet closed but without the other conditions met can cause the bar stock to pull out of the feeder collet.

Other causes that contribute to losing stock from the pusher collet are:

  • Looseness in the linkage of the sync device
  • worn rotating tip
  • obstructions to the bar pusher in the channel or nose
  • slack in the synchronization or drive belt
What parameters or settings do I have to change when setting up a new job?

All controls:

These instructions cover the following controllers:

  • FMB Omron (Touchscreen) Control
  • FMB Omron (Pre Touchscreen) Control

When changing to a new job the part length parameter in the [PART] menu, [Standard Settings] should be changed.

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 first insert 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:

  1. Locate the [Extension of First Insert] parameter, located in the [PART] menu under the [Special Settings] section.
  2. Adjust this parameter to allow the new bar to travel farther into the lathe, at bar change, by the distance of the entered value.

The [Speed] and [Force] for [Part Follow-up] parameters normally are not changed but can be in special cases such as extremely small or large diameters or flexible material.

These parameters can be found in the [PART] menu under the [Standard Settings] section.

Explain the dwells I need to have present in my lathe program to accommodate the bar feeder?

All controls:

These instructions cover the following controllers:

  • FMB Omron (Touchscreen) Control
  • FMB Omron (Pre Touchscreen) Control

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 allows the synchronization device time 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.

How do you set the chain/belt tension on my bar feeder?

FMB Omron touchscreen controls:

The drive belt tension is adjusted by moving the drive motor toward the rear of the bar feeder.

To adjust the drive belt tension:

  1. Remove the front panel of the bar feeder. The panel is in two sections, only the section to the rear needs to be removed.
  2. Loosen the three bolts that attach the motor bracket to the beam of the bar feeder.
  3. Loosen the two bolts on top of the magazine plate.
  4. Push the motor assembly to the rear to tension the belt.
  5. Re-tighten the 5 bolts.

FMB Omron pre touchscreen:

The drive belt tension is adjusted by moving the drive motor toward the rear of the bar feeder.

To adjust the drive belt tension:

  1. Remove the front panel of the bar feeder. The panel is in two sections, only the section to the rear needs to be removed.
  2. Loosen the three bolts that attach the motor bracket to the beam of the bar feeder.
  3. Loosen the two bolts on top of the magazine plate.
  4. Push the motor assembly to the rear to tension the belt.
  5. Re-tighten the 5 bolts.
How do I determine which bushing block (bearing block) to use in my steady rest for a specific bar stock diameter?

FMB Omron touchscreen controls:

The bushing blocks have an approximate range of two millimeters with a clearance of one millimeter.

For example, the 10mm bushing block has a stock size range of 7mm to 9mm and the 15mm bushing block has a size range of 13mm to 14mm.

NOTE: The blocks are sold individually, it takes 2 blocks to make a set.

FMB Omron pre touchscreen:

The bushing blocks have an approximate range of two millimeters with a clearance of one millimeter.

For example, the 10mm bushing block has a stock size range of 7mm to 9mm and the 15mm bushing block has a size range of 13mm to 14mm.

NOTE: The blocks are sold individually, it takes 2 blocks to make a set.