Linear Shafts
The shaft is half of every linear bushing system — its hardness, roundness and surface finish set the accuracy and life of the motion.
What are linear shafts?
A linear shaft is an induction-hardened, precision-ground round bar on which linear ball bearings or plain bushes run. Shafts are specified by diameter tolerance (commonly g6/h7 class fits), surface hardness and straightness, and are routinely supplied with machined ends — threads, steps, flats — to suit the machine design.
Typical materials
Typically SUJ2 bearing steel or induction-hardening carbon steel, hard-chrome-plated options; stainless (SUS440C class) where corrosion matters.
Types of linear shafts
Plain linear shafts
Full-length ground shaft, cut to length.
End-machined shafts
Threaded, stepped or drilled ends to drawing for direct assembly.
Hollow shafts
Weight-reduced versions for moving-shaft designs.
Stainless / plated shafts
Corrosion-resistant options for wet or clean environments.
How to select linear shafts
- Diameter and tolerance class matched to the bearing.
- Length, straightness and support spacing to limit deflection.
- Surface hardness for ball-bearing running.
- End machining details — send a drawing for exact quotation.
Not sure? Send what you have — a part number, drawing or photo — and our engineering team will confirm the selection.
Frequently asked questions
- What tolerance are linear shafts supplied to?
- Standard shafts for linear ball bearings are ground to a g6 or h7 class diameter tolerance with controlled roundness and straightness — matching the bearing maker's recommended fit.
- Can shafts be supplied with machined ends?
- Yes — threads, steps, flats and mounting holes are standard options. Send your drawing through Request a Quote and we will quote the machined shaft complete.
Related components
Linear Bearings
Linear bearings put recirculating balls between shaft and carriage, turning sliding friction into smooth rolling motion.
Linear Guide Rails
Profile rail guides carry heavy, offset loads with high rigidity — the standard motion element of machine tools and automation axes.
Oil-Free Bushings
Oil-free bushings run without lubrication lines — solid lubricant embedded in the bearing wall feeds the sliding surface continuously.
Need linear shafts?
Tell us the specification, quantity and application — or just send the drawing.