Dunham CNC Lathe Bar Pullers

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What does the bar puller do?

Rovi distributes high quality lathe bar pullers and bar puller kits to enhance bar stock puller applications. These bar pullers are most frequently used as CNC bar pullers, but are also used in ‘pick and place’ applications. These tools are sometimes referred to as pull up bars.

Grippers for CNC lathes are available from 1/8″ to 2″ diameters (1/16″ increments) as well as 2 1/4″ & 2 1/2″ sizes and mount directly to the Dunham bar pull shank or bar pull adapters.

The lightweight and self-activating bar puller has no moving parts, mounts in 60 seconds with gripper change in about 30 seconds, and does not interfere with other tools or cause turret imbalance. When a bar puller is used, the lathe turret no longer acts as a stock stop, reducing turret degradation and eliminating expensive, space-consuming, high maintenance bar feeds.

Employing a shank (available in seven diameters from 1/2″ to 1 1/2″) that is clamped in the lathe turret in the same manner as a boring bar, the grippers are hand turned onto the shank thread or onto adapters that attach to the shank to accept smaller diameter grippers. These self-activated grippers are slotted like standard collets and, as they advance over the bar to be pulled, are forced open to firmly grasp the bar for pulling out of the spindle to a programmed length. Only 1/4″ bar engagement is needed. Gripping and release of the bar are automatic when the turret is advanced and retracted. CNC bar pull components are available individually or in kits. Bar pull shanks should be specified to the size of the boring tool holders.

Demonstration video of the bar puller in a Haas SL-10. With limited room for a bar feeder, the bar puller is used here to automate production. It’s shown pulling a 4 foot long 1 inch diameter stainless steel bar. The bar is supported in the draw tube by a spindle liner made from PVC pipe.

Features and Benefits

  • Bar pull shanks fit in most boring tool holders
  • Low cost bar pull gripper replacements
  • Pull bar to last usable part length
  • Pull positions bar +/- 0.001″
  • Works close to chuck or collet nose
  • Does not interfere with adjacent tools or turret movement
  • Only 1/4″ bar engagement required

How it works…

  1. Mount shank in turret; screw on adapter (if required) and gripper.
  2. Insert bar through back of spindle and clamp with collet or chuck.
  3. Face off minimum 1/4″ projection using parting off command in CNC program.
  4. Index turret to bar pull and traverse turret toward spindle for programmed distance, sliding gripper over stock.
  5. Release clamping pressure on bar.
  6. Retract turret programmed distance.
  7. Reclamp bar.
  8. Retract turret sufficiently to clear gripper from bar.
  9. Begin programmed machining cycle.
  10. Repeat until all of bar is used.

Bar Puller Kits Contain the Following Components:

Part Number Description
BAR-PULL-KIT-1 11 Grippers (1/4″ to 1 1/2 in 1/8″ increments) plus 5/8″ and 1″ adapters. (Pictured)
BAR-PULL-KIT-2 4 Grippers (1 5/8″ to 2″ in 1/8″ increments) plus 1″ adapter.
BAR-PULL-KIT-3 6 Grippers (3/16″ to 1/2″ in 1/16″ increments) plus 5/8″ adapter.
BAR-PULL-KIT-4 8 Grippers (9/16″ to 1″ in 1/16″ increments) plus 5/8″ and 1″ adapter.
BAR-PULL-KIT-5 4 Grippers (1 1/8″ to 1 1/2 in 1/8″ increments) plus 1″ adapter.
BAR-PULL-KIT-6 14 Grippers (3/16″ to 1″ in 1/16″ increments) plus 8 grippers (1 1/8″ to 2″ in 1/8″ increments) plus 5/8″ and 1″ adapter.
All kits above require choice of one Bar Pull Shank (Order Here)
BAR-PULL-KIT-7 Special Kit for Gang Tool CNC Lathes
10 Grippers (3/16″ to 3/4″ in 1/8″ increments);
all grippers mount directly to Bar Pull Shank PB0625GT, no adapters required (this kit only);
Bar Pull Shank PB0625GT (5/8″ GT) included (this kit only).

For Details, Specs & Online Ordering, Click Bar Puller Kit or Parts Below…