Installing a Z-Axis Coarse Fine Feed Locking Spacer
By Products for bench top machinists | LittleMachineShop.com | Published: 2026-10-21
Category: How-to Guides
Learn how to install a Z-axis coarse/fine feed locking spacer on your bench mill to eliminate unwanted quill movement during fine adjustments.
Quick answer
Install the Z-axis coarse/fine feed locking spacer between the quill lock hand wheel and quill pinion pivot on your HiTorque or SIEG SX2.7 bench mill to stop the quill from drifting during fine feed adjustments.
Why you need this spacer
If your bench mill's quill creeps down when you switch from coarse to fine feed, the Z-axis locking spacer solves that. It sits between the quill lock hand wheel and the quill pinion pivot, creating enough friction to hold position without overtightening. Without it, the hand wheel can loosen during operation, letting the quill drop unexpectedly.
The spacer is a simple, low-cost fix—about $1.27 from LittleMachineShop—and works on both HiTorque bench mills and the SIEG SX2.7. No modifications to the mill are required.
What you'll need
Gather a 10mm wrench or socket, a small flathead screwdriver, and the spacer itself. Have a clean rag handy to wipe any debris from the quill area before installation.
Installation steps
- Step 1: Remove the quill lock hand wheel: Use a 10mm wrench to loosen the nut behind the hand wheel on the left side of the mill head. Slide the hand wheel off the quill pinion pivot shaft. Watch for the small key or set screw that may fall out—keep it safe. Check if a key or set screw is present; if missing, the hand wheel may slip on reassembly.
- Step 2: Place the spacer on the pivot shaft: Slide the Z-axis locking spacer onto the quill pinion pivot shaft, flat side facing the mill head. The spacer should fit snugly against the shoulder of the pivot. Do not force it—if it binds, check for burrs on the shaft. Ensure the spacer sits flat; a tilted spacer will cause uneven wear or binding.
- Step 3: Reinstall the hand wheel and tighten: Slide the hand wheel back onto the pivot shaft over the spacer. Replace any key or set screw. Tighten the nut with the 10mm wrench until the hand wheel has slight resistance when turned—do not overtighten, or the coarse/fine feed mechanism may bind. Overtightening can damage the feed mechanism; aim for a snug fit that still allows smooth rotation.
- Step 4: Test the feed lock: Engage the fine feed and turn the hand wheel. The quill should not drift when you release the handle. Switch to coarse feed and confirm the spacer holds the quill in place. If it still creeps, tighten the nut slightly more. If the quill still moves, verify the spacer is the correct part for your mill model—HiTorque and SIEG SX2.7 use the same spacer, but other mills may differ.
Product details
- Spacer, Z-Axis Coarse/Fine Feed Locking, Bench Mill: This Z-axis coarse/fine feed locking spacer fits between the quill lock hand wheel and the quill pinion pivot on HiTorque bench mills and SIEG SX2.7 bench mills. It prevents the hand wheel from loosening during use, so your fine feed adjustments stay accurate without the quill creeping.
Spacer, Z-Axis Coarse/Fine Feed Locking, Bench Mill
