Ball Screw Reconditioning

Barnes Industries has been reconditioning ball screws for over four decades.

We actually pioneered the ball screw service industry in 1969. Barnes specializes in reconditioning all types of ball screw assemblies with internal or external ball return systems.

When your CNC machine tool begins to lose its accuracy, the ball screws and the thrust bearings on the journals are usually the cause. Send your worn or damaged ball screw to us for a complete evaluation. To determine the cost of reconditioning a ball screw, it should be shipped prepaid to Barnes Industries for a no-charge inspection. Remove all end bearing assemblies prior to shipping.

Ball Screw Inspection Process

Our detailed inspection and engineering analysis of the failed ball screw assembly often pinpoints serious application or installation problems with the machine tool. These will be addressed by our sales staff and will be available to purchasing, engineering or maintenance personnel as needed on a detailed quote.

This valuable information can be used to properly correct the machine tool and extend ball screw life. The Barnes sales team will contact you for a purchase order approval before carrying out any operation. Your ball screw information is entered into our extensive database and kept on permanent file. Call us today to see how Barnes ball screw reconditioning can decrease your downtime.

  • Photographed as received, to properly identify nut direction. Kept on permanent file.
  • Inspected for running condition and evidence of any preload on the ball nut.
  • Complete disassembly of the unit.
  • Thorough cleaning and visual inspection under magnification of all components.ball screw reconditioning
  • Ball screw and ball nut raceways are checked for wear as well as metal fatigue.
  • The hardness of the screw raceway is inspected on the major and root diameters.
    (The hardness will affect the warranty on the reconditioned ball screw assembly)
  • The ball screw, if in good condition, is inspected for straightness and lead accuracy.
  • Screw journal diameters are inspected for size against thousands of engineered drawings.
  • Snap ring grooves, V-threads, and keyways are also inspected.
  • The ball return system in the ball nut is inspected for wear and damage.
  • The seals are inspected for damage or contamination with machining chips or debris.
  • Comprehensive analysis and detailed report is completed.
  • Engineering evaluation for cause of failure is performed.
  • Proposed solution for increased ball screw life or expedited delivery if required.

Ball Screw Regrinding Service

Economically feasible for servicing all types of damaged precision and semi-precision ball screws. The regrinding process includes:

  • Engineering analysis of screw hardness, extent of damage, physical measurements and depth of raceway wear, to determine amount of safe stock removal to ensure long life and service warranty.matrix-70-thread-grinder
  • Evaluation and engineering assessment of all mounting journals; including bearing diameters, V-threads, keyways, snap ring grooves, oil seal diameters, etc.
  • Engineering authorized drawings and process documentation to assure accuracy.
  • Process control assignment of thread grinding equipment and personnel.
  • Straightening of screw shaft between centers, inspecting all diameters and screw thread.
  • Processing journal diameters for chrome plating and grinding to ABMA tolerances.
  • Grinding major diameter if needed to ensure accuracy in thread grind and to remove any corrosion or other damage from use.
  • Set up and indicate ball screw in precision thread grinder.
  • Grind ball thread to engineered specifications to properly remove all damaged areas of the raceway and to generate an accurate lead on the screw.
  • Optical inspection of screw radius to assure proper ball conformity.
  • Straighten the ball screw between centers as needed before, during and after the thread grinding process.
  • Lead check the screw thread at the required intervals for the lead specified.
  • Record all thread profile accuracies and lead on permanent file.
  • Lead accuracy inspections are available for all reconditioned screws at customer request.

Ball Screw Reconditioning Service

New nuts for reconditioned ball screws can be made with the original mounting configurations. In most cases, the Barnes new nuts are engineered for increased mill-dept-retrofitload carrying capacity, which in turn ensures the longevity of the ball screw. Any application information (operating load, speed, vibrations, contamination, lubrication, etc.) that can be made available to our sales department will help assist the Barnes engineers in their design of your replacement ball nut. Whenever possible, always include machine make and model, screw part number and axis. Our engineers work diligently to improve every ball screw design for maximum load capacity and life. See how we can assist you with increasing the life of your ball screws.

In cases where the ball screw cannot be reconditioned, we custom manufacture new replacement ball cnc-lathescrews with extremely short deliveries. We have a complete range of in-house tooling, thread grinding, milling, turning, straightening, lead checking, and inspection equipment to recondition or manufacture new ball screws with diameters up to 6" and lengths up to 52'..

Several machine tool manufacturers recommend our services for reconditioning their customers damaged ball screw assemblies.

Reconditioning Process

With a commitment to provide dedicated solutions for your unique needs, Barnes adopts a step-by-step ball screw reconditioning process, which involves:

visual-inspection-of-worn-nut1. Visual Inspection of Worn Nut

Optical-Comparator-Incoming2. Optical checking of warn lead screw thread radius to determine radius wear and deformation.

grinding-ball-thread-matrix-703. Grinding lead screw ball raceway in a Matrix 70 thread grinder.

Straightening-Screw4. Straightening of ball lead scew before lead check.

lead-check5. Checking thread lead in a master V-block.

Turning-new-ball-nut6. Pre-cutting internal ball thread raceway in a new ball nut before heat treatment.

inspecting-timing-of-return-holes7. Inspecting timing of ball thread return holes with ball thread raceway before heat treatment.

Checking-hardness-on-ball-nuts8. Checking hardness on ball nuts after heat treatment.

Grind-ball-thread-raceway-in-new-ball-nut9. Grind ball thread raceway in new ball nut

Optical-checking-of-reground-lead-screw-thread-radius-to-new-engineered-specifications10. Optical checking of reground lead screw thread radius to new engineered specifications.

Inspecting-radial-clearance-to-determine-ball-contact-angle11. Inspecting radial clearance to determine ball contact angle

Checking-drag-force-and-running-condition-old-scale12. Checking drag force and running conditiong of flange-type nut assembly.

Checking-journal-concentricity13. Checking journal concentricity to pitch diameter of ball screw, by rotating screw through nut.

Testing-axial-deflection-between-nut-and-ball-screw-to-determine-point-at-which-preload-is-relieved14. Testing axial deflection between nut and ball screw to determine point at which preload is relieved

Checking-a-flanged-nut-for-squareness15. Checking a flanged nut for squareness to the screw axis, and journal concentricity to the screw major diameter

Checking-leadscrew-centerline16. Checking leadscrew centerline, and cetnerline angularity on a reconditioned ball screw

Send your worn or damaged ball screw assembly to Barnes industries for a no-charge inspection and see what Barnes can do for you.


Extra Long Ball Screw

Reconditioning of Large Buttress Screw 

High Load Capacity Ball Screw 




Alloy Steel
Hardened Steel
Stainless Steel


Thread Grinding
Cylindrical Grinding
Induction Hardening
Flame Hardening
Furnace Tempering
Thread Whirling
Deflection Testing
Lead Inspection
Inspection and Testing

Special Services

Design Assistance
Emergency Reconditioning
Reload and Minor Reconditioning
Repair Broken Journals
Detailed inspection of failed ball screw assemblies
Diagnose machine tool discrepancies leading to failure
Pinpoint ball screw application errors
Identify alignment related premature ball screw failures

Maximum Screw Diameter

6" (Larger sizes can be handled upon request)

Maximum Screw Length

52' (Longer lengths can be handled upon request)

Screw Lead Accuracy (Tolerance)

Reloaded Ball Screws:
Customers will be notified of lead accuracy.

Ball screws Reconditioned by Lapping:
Customers will be notified of lead accuracy.

Ball screws Reconditioned by Regrinding:
±0.0005" per Foot, Cumulative

Precision Ball Diameter Tolerance

+/-0.000025" (Grade 25)


  • The cost of reconditioning required for your ball screw assembly is determined from a no-charge inspection.
  • When the type of servicing and costs are determined, the customer is notified with a written report/quotation for a purchase order approval before any other operations are carried out.


  • Backed by the support of our experienced staff and state-of-the-art equipment, we provide fast delivery time on all our reconditioned ball screws to reduce customer downtime to a minimum.
  • Delivery time is determined by the size of the screw and the extent of the damage.
  • Expedited service is available in many cases.


  • Barnes Reconditioned ball screws are given an in-service warranty.
  • For our lapped ball screws, we provide a warranty of 12 months.
  • For reground ball screws, we provide a warranty of 15 to 18 months. (Ball screw raceway hardness must be Rc-58 minimum for full 18-month warranty to apply.)

Service Advantages

  • Industry pioneer for ball screw service
  • No-charge initial inspection
  • Fast turn-around time
  • Engineered to a high load capacity and life rating
  • All our ball screws are tested and preloaded to manufacturers' specifications
  • Complete in-house machinery to recondition ball screws of any size and design
  • Unequaled ball screw design and equipment engineers on staff

Grinding Equipment

Thread Grinders: MATRIX 70, Mitsui-Seiki, Excello, Jones & Lamson

Standards Met

Ball Screw Standards: ANSI, ISO, DIN, and JAS
ISO 3408 and DIN 69051
American Bearing Manufacturers Association's (ABMA's) Class ABEC-5 Standard

Industries Served

Machine Tool
Machine Tool Rebuild
Material Processing
Power Generation

Partial Client List

Baker Oil
Dainichi Machinery
GE Aircraft Engine
General Dynamics
Hess Industries
John Deere
Parker Hannifin
Peiffer Machine
Solar Turbines
Spirit AeroSystems
The Daniluk Corp.

Call 248.541.2333 Today visit our faq page for more information