Last updated: 03/26/2025

Lathe - Spindle Vibration - Tolerances

Introduction

This document contains the Displacement (MIL) and Velocity (in/s) vibration tolerances for lathe spindles. Refer to following procedures for spindle Vibration Analysis instructions:

  1. Vibration Analysis - RS-232 Interface. For use with a vibration analyzer that has an RS-232 interface.
  2. Vibration Analysis - Ethernet Interface. For use with a vibration analyzer that has an Ethernet interface.

Note: Each interface has different software and Cycles Per Minute (CPM) ranges. You must take more measurements if you use the Ethernet interface.

Vibration Displacement - Tolerance Plot Ranges:

Observe the Displacement Plot (MIL) within the correct CPM range depending on the type of vibration analysis interface you are using per the table below. Check the tolerance based on spindle type as shown in the table below.

Spindle Type Max Allowable Spike RS-232 Interface Ethernet Interface
TL-1/2/3 0.05 MIL 0-33,000 CPM 0-38,452 CPM
TL-3B 0.09 MIL
ST-10/15/20/30/40 0.08 MIL
OL-1 0.10 MIL
CL-1 0.05 MIL

Vibration Velocity - Tolerance Plot Ranges:

Observe the Velocity Plot (in/s) for the following CPM ranges depending on the vibration analysis interface you are using.

The tolerance for all lathe spindles is as follows: 

  • No more than a total of 3 spikes to exceed .005 in/sec across all CPM ranges (30,000 - 213,000 CPM) or (38,452 - 230,713 CPM) depending on the interface.
  • The CPM ranges for each interface are listed in the table below.  Take a screenshot for each range when performing a test.
RS-232 Interface Ethernet Interface
0 - 33,000 CPM 0 - 38,452 CPM
30,000 - 93,000 CPM 38,452 - 76,904 CPM
90,000 - 153,000 CPM 76,904 - 115,356 CPM
150,000 - 213,000 CPM 115,356 - 153,809 CPM
  153,809 - 192,261 CPM
192,261 - 230,713 CPM

EXAMPLES OF LATHE SPINDLE VIBRATION DISPLACEMENT PLOTS:

TL-1 - 2K Spindle - Displacement Plot

The image below shows the Vibration Displacement plot for a TL-1 with a max speed of 2,000 RPM.

The CPM range is 0-33,000 CPM.

Look at the spike at the maximum RPM.

In this case, the spike is under 0.05 MIL.

The spindle passes the Vibration Displacement test.

CPM Vibration Displacement Graph
TL-1 - Vibration Displacement graph, 0-33000 CPM

ST-10 - 6K Spindle - Displacement Plot

The image below shows the graph for Vibration Displacement for a ST-10 spindle with a max speed of 6,000 RPM.

The CPM range is 0-33,000 CPM.

Look at the spike at the maximum RPM.

In this case, the spike is under 0.08 mil.

The spindle passes the Vibration Displacement test.

CPM Vibration Displacement Graph
6K Spindle - Vibration Displacement graph, 0-33000 CPM

EXAMPLE OF A LATHE SPINDLE VELOCITY PLOT:

The images below show the Vibration Velocity plots for a DS-30SS 4,800 RPM spindle.

In this case, there is only one spike that is over 0.005 in/s between 20,000 and 210,000 CPM.

Thus, the spindle passes the Vibration Velocity test.

CPM Vibration Velocity Graph
4.8K Spindle - Vibration Velocity graph, 0-33000 CPM
4.8K Spindle - Vibration Velocity graph, 30000-93000 CPM
4.8K Spindle - Vibration Velocity graph, 90000-153000 CPM
4.8K Spindle - Vibration Velocity graph, 150000-213000 CPM