Conform-A Products

Problem Solvers for Thin-Walled Parts

Hydra-Lock’s most recent innovations in hydraulic work-holding technology are our Conform-A Products including our Conform-A-Chuck® and Conform-A-Arbor®. These revolutionary new work-holding products utilize Hydra Fibre®, a special plastic material with the ability to hold an out-of-round part effectively without rounding it up. Hydra Fibre® conforms to the part, giving it a good memory, high coefficient of friction, excellent wear characteristics and allowing for levels of expansion up to .125” (depending on size).

Conform-A-Chuck® and Conform-A-Arbor® are designed for OD or ID applications. They grip the diameter firmly for machining operations like boring, honing or grinding without squeezing and deforming the workpiece round, making them the perfect work-holding solution for thin-walled parts, such as:

  • Automotive smog control air pump rotors
  • Gas turbine parts
  • Thin-wall tubing
  • Cylinder liners for all engine types, including: Farm Equipment, Locomotives and Trucks



  • Class: C
  • Actuation: Direct pressure or self-contained hydraulic system
  • Mounting: Stationary-mounted in-line with spindle (can be rotated if necessary)


  • Several independent pressure systems can be applied if required by part configuration
  • Air register to sense part present before cycle starts


Conform-A-Arbor® (for all engine type cylinder liners)

  • Class: C
  • Actuation: Direct pressure or self-contained hydraulic system
  • Mounting: Spindle-mounted


  • Up to .125” expansion (depending on part size)
  • Retractable stops so end face of part may be machined square and ID chamfered during same cycle in which OD is turned
  • Multiple pressure systems (if required)
  • Air register to sense part present before cycle starts
  • Arbor locates in rough-bored ID of thin-walled, heat-treated, cast-iron parts
  • Flexible Hydra-Fibre® sleeve grips the entire surface (360 degrees ´ length) and holds it securely without rounding up the out-of-round part


High Contraction Chuck/Arbor

Hydra-Lock Corporation now has a patented, remarkably high expanding/contraction design for arbors and chucks. This design allows averaging the true centerline of rough castings handling parts that are out of round .100 inch or more. For turning, boring, grinding or other machining operations without distorting the part, expansion or contracting can exceed .25 inch or more.


Real-World Results

Diesel engine cylinders are commonly held in place by our Conform-A-Arbor® during standard boring operations, because the skirt ends of the cylinder liner are easily deformed, making these parts difficult to hold.

With an approximate diameter of 5” (± .010 tolerance) ´ 10” long is usually .008” to .010” out of round, Conform-A-Arbor® can locate on the entire rough-machined surface and support the weak skirt under the machining pressure.

This allows it to establish an average center line, so the resulting bore will be within .001” or less of the total geometry.

Because Conform-A-Arbor® can be customized to meet individual requirements, it can produce a bell-mouthed, straight or choke condition at the flange end.