Idea Bulletin

Large Motorized Machining Spindle Repair  Speedy domestic spindle service saves time, money and trouble for U.S. machine tool builder


Used in the automotive and heavy equipment industries to hold brake drums, fly wheels, hubs, and rotors, differential cases and housings while machining is performed, these spindles typically produce over 2,000 brake rotors per day, the spindles themselves acting as loading/unloading devices.


The machine tool spindle being used was foreign-made, and servicing the spindles was problematic for domestic installations. Because the spindles were of a proprietary design, spindle rebuild was difficult.

Large motorized machining spindle rebuilt_2
Large motorized machining spindle rebuilt_1


With complete capabilities to perform both the engineering and the manufacturing required for the spindles’ rebuild, Gilman’s Spindle Service Center was the logical choice for faster, more economical, on-shore rebuilding.

Cost Savings

By having Gilman Precision’s Spindle Rebuilding Center do the work instead of shipping the spindles overseas, the manufacturer realized savings of thousands of dollars per spindle.

Time Line

By eliminating the time required to ship overseas, Gilman was able to reduce the turnaround time on rebuilt spindles by weeks.

Spindle Rebuild Process

  • •    Disassembly and inspection of spindles

    •    Inspect shaft-bearing journal diameters for sizing and concentricity

    •    Inspect housing-bearing bores for sizing and concentricity

    •    Re-manufacturing spindle parts as necessary and align tolerances to original specifications

    •    Inspect motor parts and repair

    •    Each spindle receives a run-off test and carries a new spindle warranty upon leaving the Gilman Precision Spindle Service Center

Technical Specifications

  • Weight:                                     1,050 lbs.

    Bearings:                                   110mm ball bearings - front 85mm cylindrical roller bearings - rear

    Max. Speed:                              4,000 RPM

    Operating Speed:                      3,000 RPM

    Max, Forces:                               Axial load: 2,300N Radial load: 9,000N

    Lubrication:                               Grease

    Running Accuracy:                     Axial and radial runout < 5µm

    Balancing Quality:                     G 2.5

    Power (100% operation:            PS1=28 kW between n=900 and 4,000 RPM

    Torque (100% operation):          Mnom S1 = 340 Nm at n=900 RPM

Large motorized machining spindle rebuilt_layout

Every care has been taken to ensure the accuracy of the information contained in this publication but no liability can be accepted for any loss or damage whether direct, indirect, or consequential arising out of use of the information contained herein.

Request A Quote

To request a quote, please contact us using the contact form.

If you have an item that we can repair for you, click the repair request forms below.

Use our product configurator to download a drawing to use in your design.

If you you would like to reach us directly, give us a call at 262-377-2434, or email us at