Service Home How To Procedures ST-30 Gearbox Non-Contact Encoder Upgrade Kit - AD0442
Last updated: 01/31/2023

ST-30 Gearbox Non-Contact Encoder Upgrade Kit

This procedure is for service kits 93-2946 (FLD UPGRADE KIT ST-30 GBOX NCE 10" CHU) and 93-2983 (FLD UPGRADE KIT ST-30 GBOX NCE 12" CHU). The only difference between the kits is parameters based on chuck size. Please be sure to verify the kit is correct for your machine.

AD0442

If Applicable: Upgrade Motor Mount Plate

1

  • If the exisiting plate is machined without holes for the 3" non-contact encoder mount: plate [1], then you need the upgraded plate [2]. that's included in the kit
  • If your machine already has plate [2] you can skip to the next section.  Otherwise follow the next steps for installation.

2

  • Break loose gearbox motor mount screws [1]
  • Loosen belt tension block screws [2]
  • Remove the spindle drive belt
  • Use lift hooks secured with hex nuts on the rear studs of the motor [3]
  • Use a lift hook secure on the motor mount plate center slot [4]
  • Float the motor and remove the gearbox motor mount screws [1]

3

  • With the motor [1] securely on the floor remove the screws that secure the motor plate [2] to the brackets
  • Remove the belt tension blocks for installation onto the new plate
  • Install the new motor mount plate
  • Install the belt tension blocks to the plate
  • Install the motor to the machine reverse of removal
  • Refer to Haas Torque Specifications
  • Leave the belt off until you have installed the new spindle home switch

Install 3" Non-Contact Encoder

1

  • The non-contact encoder (NCE) ring mount hub [1] is aluminum and sweat fit to the output of the motor shaft
  • Heat the NCE ring mount hub on a hot plate to 220° F
    • Use heat resistant gloves
  • Install to motor shaft quickly
    • Press the hub onto the shaft and hold
    • Ensure it grips and seats square before releasing
  • Wait for the hub to cool to room temperature
    • Skip to installing the home switch while the hub cools down
  • Use T-0103 [3]  (RING MOUNT FIELD INSTALL TOOL ST-30 GB) to install the non-contact encoder ring [2] to the hub [1]
    • Tighten each of the 4 screws evenly, in a pattern, to bring the ring down square with the hub
    • Remove the tool when finished
  • Install the encoder read head spacer [4] and read head mount [5] to the motor mount plate
  • Install the NCE read head [6] being sure to use (2) WASHER FLAT 0.170ID X 0.400OD before installing read head mounting screws. Use the provided shim to set the gap between the ring and the read head.
  • Torque all screws per the Haas Torque Chart

Install Spindle Home Switch

1

  • Lock the spindle
  • Break loose the hydraulic union [1] screws
  • Remove the hydraulic union and drawtube assembly
    • Note orientation of clamp/unclamp hoses before disassembly
    • Do not over tighten union drain hose when re-installing
    • Do not impact the hydraulic union. Use caution when removing and installing. 
  • Note: If your machine has a C-Axis, refer to Hydraulic Cylinder - C-Axis Motor - Brake Caliper - Rotor - Replacement - ST - DS for removing the C-Axis motor to get the brake disk off
  • Remove the union adapter [2]
  • Remove the spindle sprocket [3]
  • Remove the 6" NCE ring and read head assembly [4]
  • Remove the read head mount [5]

2

  • Install the new spindle home switch sensor ring [1]
    • Not to exceed (NTE) 0.001" total indicated runout (TIR)
  • Install the spindle home switch [2] to the switch mount [3]
  • Install the home switch mount [3] 

3

  • Installation is reverse of removal but you must indicate each component in to the following TIR in the locations shown:
    1. Spindle Sprocket: 
      • Radial Runout: NTE 0.001" TIR [1]
      • Axial Runout: 0.0005" TIR [2]
      • Install the drive belt
    2. Hydraulic Union Adapter: 
      • Radial Runout: NTE 0.001" TIR [3]
      • Axial Runout: NTE 0.0005" TIR [4]
    3. Hydraulic Union: 
      • Radial Runout: NTE 0.0005" TIR [5]
  • Adjust belt tension using the belt tension blocks
    • See belt tension chart
    • Rule of thumb: Belt should not twist more than 90° when rotated by hand
    • Once set torque the screws while securing the nut on the bottom of the block
  • Torque the motor mount plate screws
  • Re-check belt tension and verify it remained the same

Wiring and Software

1

  • Remove the old non-contact encoder cable
  • Install the new cable to the same port and trace back along the same path
  • Connect the dual port cable to the new 3" NCE and the spindle home switch
  • Secure with cable clamps as seen in the photo

2

3

  • Slowly run the spindle from 1% of max RPM up to 100% max RPM
  • Stop the spindle if there are any unusual noises from the C-Axis gears or belts.  
  • Verify spindle passes vibration