25mm Ballscrew Kit SFU2505 RM2505 1140mm - Precision Anti-Backlash

In this review the 25mm Ballscrew Kit SFU2505 RM2505 is evaluated for CNC hobbyists and light industrial use; the bottom line is it delivers precise, low-friction linear motion with a 5mm pitch and robust end supports, making it a strong choice when smooth micro-feeding and reduced driving power matter. The kit arrives as a complete assembly (1140mm length ball screw, metal nut, BK/BF20 supports and a flexible coupler) and the reviewer found the C7 precision grade and rolled GCr15 construction to provide reliable positioning without stick-slip under normal loads.

Key Features

• 25mm diameter: a stiff shaft diameter that increases static and dynamic rigidity for improved positioning accuracy on gantries and linear stages.
• 5mm lead: a moderate pitch that balances travel speed and fine feed control for CNC milling and router tasks.
• 1140mm length: long travel available out of the box to suit larger machine builds without immediate need for coupling shafts.
• C7 precision, GCr15 steel: rolled-thread construction and C7 grade tolerance deliver consistent, low-noise operation and long service life.
• Complete end supports and coupler: BK20/BF20 with locknuts and circlips plus a 14mm-bore flexible coupler reduce alignment headache at installation.

Who It's For

This kit is aimed at hobbyists upgrading DIY CNC machines, small machine shops building custom linear axes, and engineers who need a ready-made anti-backlash assembly with bearings and a coupler included. It suits projects that require higher stiffness and accurate micro-feeding without investing in bespoke machining.

Those who need ultra-high precision C5 grade, nonstandard coupler bores, or metric shaft interfaces should check compatibility before buying; the seller offers customization but builders who cannot or do not want to message for special options may look for preconfigured alternatives.

Pros & Cons

Pros

• Includes nut, BK/BF20 end supports and flexible coupler so the kit is installation-ready for many CNC setups.
• Low friction rolling motion reduces heat and driving power while eliminating stick-slip for smoother feeds.
• Good static and dynamic stiffness from the 25mm shaft helps maintain accurate positioning under load.

Cons

• Standard coupler bore is 14mm by default, so users with different motor shafts must request a change or re-bore the coupler.
• The item ships in C7 grade; users needing C5 tolerance must request that specifically.

Specifications

Model	SFU2505 RM2505
Diameter	25mm
Lead / Pitch	5mm
Total Length	1140mm (44.88 in)
Precision Grade	C7 (optional C5 on request)
Included Accessories	Metal ballscrew nut, BK20/BF20 end supports, flexible coupler (14mm bore)
Material	GCr15 steel, rolled thread

Our Verdict

The SFU2505 RM2505 25mm ballscrew kit is a practical, value-minded choice for DIY CNC builders and small shops that need reliable anti-backlash performance and a near-complete installation package. With solid stiffness, low friction and included supports and coupler, it represents good value for most projects, provided buyers confirm coupler bore size or request C5 tolerance if required.

Frequently Asked Questions

Does the kit include end supports and a nut?
Yes, it includes one metal ballscrew nut and BK20/BF20 end supports with locknuts and circlips.

What is the default coupler bore size?
The flexible coupler is supplied with a 14mm bore by default; request a different bore size when ordering if needed.

Can I get a tighter precision than C7?
Yes, the seller can provide C5 grade on request; contact them to arrange the higher precision option.