These are custom CNC machined spline shafts built from bar stock or near-net forgings, machined on 4-axis and 5-axis milling centers. You get spline profiles held to 0.005 mm total runout and 0.01 mm
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These are custom CNC machined spline shafts built from bar stock or near-net forgings, machined on 4-axis and 5-axis milling centers. You get spline profiles held to 0.005 mm total runout and 0.01 mm
These are custom CNC machined spline shafts built from bar stock or near-net forgings, machined on 4-axis and 5-axis milling centers. You get spline profiles held to 0.005 mm total runout and 0.01 mm pitch accuracy, with surface finish down to Ra 0.4 µm. Typical lead time is 5 working days for prototypes, 15 days for production runs, with hardness options from 28 HRC to 58 HRC depending on material and heat treatment.
This is precision manufacturing, not generic job shop work. Every tooth flank is cut with indexable carbide or solid carbide form cutters, then verified on a CNC gear measuring machine. If your drawing calls for a DIN 5480, ANSI B92.1, or JIS D2001 spline, we machine it exactly to the class of fit you specify — no guesswork, no rework on your side.
We use two methods depending on quantity and hardness. For soft-machined shafts (pre-heat treat), we single-point mill each tooth space with a custom-ground form cutter. For hardened blanks, we switch to whirling or skiving on a CNC lathe with live tooling. Both methods hold flank profile deviation under 0.008 mm and cumulative pitch error under 0.012 mm over 100 mm of spline length.
Heat treatment distortion is the biggest risk on long shafts. We stress-relieve after rough turning, then semi-finish, then harden, then finish grind the major diameter and tooth flanks. This sequence keeps runout between the spline pitch diameter and the bearing journals under 0.005 mm on shafts up to 600 mm long.
Most spline shafts we ship are 4140, 4340, 8620, or 17-4PH stainless. For carburized parts, we specify case depth of 0.8–1.2 mm with surface hardness 58–62 HRC. For through-hardened shafts, we target 28–32 HRC for toughness or 45–50 HRC for wear resistance on the flanks.
If you are unsure which grade fits your torque and fatigue requirements, send us your load conditions. We will recommend a material and heat treat cycle based on our experience with gearboxes, hydraulic pumps, and actuator shafts. We also stock 1045 and 4140 in diameters from 20 mm to 150 mm, so prototype lead time stays short.
Every shaft is checked on a Zeiss CMM with a rotary table. We measure major diameter, minor diameter, tooth thickness over pins, lead error, and index error. Runout is checked between centers with a 0.001 mm dial indicator. Surface finish is verified with a portable profilometer on the flank and journal areas.
We send you a full inspection report with each shipment, including the CMM data sheet and material certificates. If a dimension is out of tolerance, we do not ship it — we rework or scrap it internally. Our non-conformance rate over the last 12 months is 0.4%.
We handle spline shafts from 6 mm to 200 mm outside diameter and lengths from 20 mm to 800 mm. Module range is 0.5 to 6, with tooth counts from 6 to 60. We machine involute, straight-sided, and serrated profiles, including crowned splines for misalignment compensation.
For shafts longer than 500 mm, we use a steady rest and tailstock support to prevent deflection. We have also machined stepped spline shafts with multiple spline sections on one bar — for example, a 2-section spline with different modules on each end. This is common in transfer cases and agricultural PTO shafts.
Standard spline flank finish is Ra 0.8 µm. For high-cycle fatigue applications, we can grind or polish the flank to Ra 0.4 µm, which increases fatigue strength by roughly 15% compared to Ra 1.6 µm. Bearing journals and seal surfaces are always ground to Ra 0.4 µm or better.
If you need a phosphate coating, black oxide, or zinc-nickel plating, we do that in-house or with our certified local supplier. Coatings are applied after final grinding so the spline geometry is not affected. For stainless steel shafts, we offer electropolishing to remove micro-burrs and improve corrosion resistance.
Each shaft is individually wrapped in VCI paper, placed in a foam-lined wooden box, and strapped. For long shafts over 400 mm, we use a reinforced plywood crate with foam cradles. We also include a paper copy of the inspection report and material cert inside the crate.
All export paperwork — commercial invoice, packing list, and certificate of origin — is prepared by our shipping team. We ship via DHL, FedEx, or sea freight depending on your urgency. For prototypes, DHL Express typically delivers to the US or Europe in 3–4 working days after inspection.
If your drawing specifies a DIN 5480 class 7e or ANSI B92.1 class 5, we adjust our machining parameters accordingly. For class 5, we use a finish grinding pass on the tooth flanks after heat treatment. This is slower but yields tooth thickness variation under 0.005 mm and surface finish Ra 0.2 µm.
We also check the fit with a master spline gauge — both a go and no-go gauge — before shipment. This confirms the actual fit class, not just the dimensional data. If you need a mating spline hub or bushing, we can machine that as well to guarantee the fit.
We keep two CNC lathes and one 5-axis mill dedicated to prototype work. For a single piece with standard material (1045 or 4140), we can ship in 3 working days. For 10-50 pieces, plan on 7-10 working days. Production orders of 500+ pieces typically run 3-4 weeks, including heat treatment and grinding.
There is no MOQ for standard spline profiles. We accept one-piece prototypes and scale up to your volume. For repeat orders, we retain your CNC programs and inspection fixtures, so the second order is always faster and cheaper.
Send us a PDF or STEP file of the spline shaft drawing. Include the spline standard (DIN, ANSI, JIS), module, tooth count, pressure angle, and fit class. Also specify material and hardness if you have a preference. If you do not have a drawing, send a sample part and our engineers will reverse-engineer the spline geometry.
We will reply with a firm quote within 12 hours on business days. The quote includes unit price, tooling cost (if any), lead time, and freight options. For complex multi-section splines, we may ask for a 30-minute video call to clarify geometry before quoting.
We have shipped over 12,000 custom spline shafts in the last five years. Our customers are in hydraulic equipment, agricultural machinery, robotics, and electric vehicle drivetrains. We do not outsource any machining or inspection — everything is done inside our 8,000 m² facility in Dongguan.
Our quality system is ISO 9001:2015 certified. We also comply with RoHS and REACH for material and coating content. For defense or aerospace applications, we can provide a full chemical and mechanical test report per EN 10204 3.1.
If you are selecting cutting tools for spline machining, review our CNC cutting tool selection guide for carbide grade and coating recommendations. For a deeper look at how tolerances are applied to spline shafts, read our CNC machining tolerances guide which covers fit classes and measurement methods.
| Parameter | Capability |
|---|---|
| Outside Diameter Range | 6 – 200 mm |
| Length Range | 20 – 800 mm |
| Spline Module | 0.5 – 6 |
| Tooth Count | 6 – 60 |
| Material Options | 1045, 4140, 4340, 8620, 17-4PH, 303/316 SS |
| Hardness (Through-Hardened) | 28 – 50 HRC |
| Hardness (Case-Hardened) | 58 – 62 HRC, case depth 0.8 – 1.2 mm |
| Total Runout (Spline to Journals) | 0.005 mm |
| Flank Surface Finish | Ra 0.4 – 0.8 µm (grind optional) |
| Lead Time (Prototype) | 3 – 5 working days |
| MOQ | No MOQ (1 piece accepted) |
No MOQ — we accept one-piece prototypes and scale up to any volume, and our CNC programs and fixtures are stored for repeat orders.
Yes, we use CBN grinding or whirling for hardened flanks up to 62 HRC, which eliminates distortion and achieves better than class 5 fit.
We use a Zeiss CMM with rotary table for pitch and runout, plus a go/no-go master spline gauge to confirm the fit class.
For standard materials and profiles, 15 working days including heat treatment and final grinding; rush orders can be expedited to 7 days.
Send your spline shaft drawing to sc@bquq.com or WhatsApp +86 13713157787. We will confirm the spline standard, material, and heat treat, then return a firm quote with lead time. For design help or material selection, our engineers are available for a quick call — no obligation.
Precision manufacturing made in China, with no MOQ and direct access to the factory floor. Your custom spline shaft is one drawing away from a quote.
| Parameter | Capability |
|---|---|
| Materials | AL6061/7075, SUS303/304/316, 45# steel, T2 copper, H59 brass, POM, PEEK, nylon |
| Tolerance | ±0.005mm standard, ±0.003mm on request |
| Machines | 3/4/5-axis CNC, turn-mill, Swiss lathe |
| Surface | Anodizing, nickel, zinc, passivation, sandblast, polish |
| Size Range | Max 400 x 300 x 200 mm |
| Prototype | 72 hours, no MOQ on samples |
| Inspection | Full report per batch, CMM data on request |
