What are the differences between rolled and ground ball screws?
Choose by the machine accuracy requirement, not by the process name. Rolled ball screws are formed by rolling and usually have better cost and delivery. Ground ball screws use grinding to achieve higher accuracy and more stable geometry for demanding positioning axes.
| Comparison point | Rolled ball screw | Ground ball screw |
|---|---|---|
| Forming process | Threads formed by rolling | Rolled, then ground |
| Accuracy grade | Typically C7 and above | C5 and tighter |
| Cost | Lower | Higher |
| Lead time | Shorter, batch friendly | Longer |
| Backlash / preload | Standard preload | Low backlash, stable preload |
| Surface & geometry | Good enough for general applications | Tighter geometry control |
| Typical use | Woodworking CNC, packing, general automation, distributor stock, repair | Precision positioning, inspection, demanding OEM axes |
| Inspection | Standard report | Detailed report available |
Rolled screws fit many practical projects
CNC routers, packing machinery, general automation, distributor stock, and repair replacement often use rolled ball screws. If C7 or similar accuracy is acceptable, rolled screws are often the practical choice. Review standard ball screws when the required diameter, lead, length, and nut arrangement are already defined.
Ground screws fit demanding axes
When the machine requires C5, low backlash, stable preload, higher positioning accuracy, or inspection reports, evaluate a ground ball screw. Drawings, accuracy grade, and inspection method should be clearer.
What buyers should compare before requesting a quote
- Machine accuracy and repeatability requirement.
- Screw diameter, lead, travel, speed, load, and mounting orientation.
- Required grade, preload or backlash requirement, end machining, inspection, quantity, and delivery target.
For replacement work, also send old-part photos and dimensions so the required ends and assembly details can be checked before quotation.
FAQ
Is a ground ball screw always better than a rolled one? Not automatically. Ground screws give tighter accuracy and geometry control but cost more and take longer to produce. For many standard machines, repair replacements, and general automation, rolled screws are the practical choice. Select by the application's accuracy requirement.
How do I know which type my machine needs? Check the drawing or specification for the accuracy grade. Choose ground when C5 or tighter, low backlash, or stable preload is required; start with rolled when C7 or no grade is specified for a conventional machine.
Why is the price difference between rolled and ground screws so large? The forming process. Rolled screws are formed in one pass; ground screws add a grinding operation after rolling, with stricter geometry control and inspection, which raises cost.
Next step
Turn this guide into an RFQ
When the specification direction is clear, send the details below together with quantity, lead time, and packing requirements.
Include these details
- Model, diameter, lead, accuracy grade, or target application.
- Load, speed, travel, mounting method, and matching rail or support-unit needs.
- Quantity, lead time, packing, and whether inspection records or shipment photos are needed.
Category
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