What C7 accuracy means
C7 is a ball screw accuracy class whose lead error is controlled within the standard range but looser than C5. The number 7 is the class, not the diameter or length. C7 screws are the most common on the market with good stock, short lead time, and a lower price. It is sometimes written as a C7 ballscrew or C7 ball screw; both spellings mean the same accuracy class.
Where C7 fits
- Ordinary CNC engraving and woodworking machines: modest positioning requirements, C7 is enough.
- 3D printers and desktop equipment: light load and low cost, C7 is the mainstream choice.
- General automation equipment: conveying, handling, and simple positioning where value matters.
C7 or C5
The main differences between C7 and C5 are lead error and price. Machining centers, mold equipment, and precision positioning suggest C5, while ordinary machines and general automation work with C7. Before choosing C5, confirm whether the higher accuracy is really needed so you do not pay for accuracy you will not use.
RFQ points
- Specification: shaft diameter, lead, overall length, and working travel.
- Accuracy class: C7, written in the model or notes.
- Nut and preload: whether a preloaded nut is needed to remove backlash.
- End machining and support: fixed side, support side, and coupling-end dimensions.
FAQ
Is C7 accurate enough for CNC?
For most ordinary CNC and woodworking machines, yes. Machining centers or precision engraving should choose C5.
Do you stock C7 screws?
C7 is a regular stock class. Common sizes such as 1605, 1610, 2005, and 2510 are usually in stock with a shorter lead time than C5.
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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