Precision Commutator Turning Service (Skim Turning & Resurfacing)
Restore concentricity, reduce brush wear, and improve commutation. We machine new and used commutators with controlled runout and surface finish—backed by inspection reports.
What We Machine
We provide commutator turning for:
DC motor commutators (new production and refurbishment)
Segment and solid commutators
Copper / copper alloy commutators; other materials by review
Typical issues we correct
Runout / concentricity drift
Ovality caused by wear or improper clamping
Grooving and glazing
Uneven surface that accelerates brush wear
Minor damage requiring resurfacing
Capability & Tolerances
Important: Final tolerances depend on incoming condition, datum availability, and remaining material. We confirm feasibility after reviewing drawings or samples.
| Item | Typical Capability | Notes |
| Commutator diameter | 2.5 mm – 350 mm | Based on part geometry and fixturing |
| Commutator length | 10 mm – 500 mm | Accommodates standard and extended shafts |
| Stock removal | 0.05 – 0.25 mm | Typical skim turning; heavy damage reviewed case-by-case |
| Surface roughness (Ra) | 1.0 – 1.5 μm | Can be optimized for specific brush grade requirements |
| Ovality / roundness | ≤ 0.015 mm | When incoming condition and datum accuracy allow |
| Cutting speed | 200 – 600 m/min | Typical window; depends on diameter & material |
| Feed rate | 0.05 – 0.5 mm/rev | Typical window; depends on tooling & finish target |
Tooling & Method
Advanced tooling for stable surface finish
Dedicated commutator turning fixtures and precise alignment procedures
Appropriate tooling selection for copper: PCD (Polycrystalline Diamond) or micro-grain carbide based on condition and finish target
Controlled cutting parameters and finish passes for consistent surface texture
Optional operations (if required):
Mica undercutting / groove opening
Edge chamfering / deburring
Precision cleaning and vacuum protective packaging
Process
Quote & DFM (within 12 hours)
Send drawings (PDF/DWG/STEP) or ship samples. We confirm datum strategy, stock removal, and inspection plan.
Incoming inspection
Visual check + key dimensions + runout baseline. We assess whether the part has enough material for resurfacing.
Setup & alignment
We align to the defined datum (shaft/bore/OD per drawing). For refurbishment parts, we select the most reliable datum based on wear patterns.
Skim turning / resurfacing
Rough pass (if needed) → finish pass for target Ra and concentricity.
Deburr, clean, and protect
Remove sharp edges and chips; clean the surface; protect against oxidation and handling damage.
Final inspection & report
We measure critical dimensions and runout. Inspection report provided.
Lead Time & MOQ
Typical lead time
Samples / small batch: 3–5 business days after confirmation
Production batch: 10–15 business days depending on quantity and operations
MOQ
No MOQ for quotation
Production MOQ: 10 pcs depending on part type and setup requirements
What You Need to Send Us
To quote accurately, please provide:
Drawing with critical tolerances (PDF/DWG/STEP preferred)
Material/spec (copper grade if known)
Quantity and target delivery date
For refurbishment: photos of current condition and whether the commutator has been previously turned
Required operations: turning only / turning + undercutting / deburr / cleaning / packaging
Accepted file types: PDF, DWG, STEP, IGS, X_T, SLDPRT, ZIP
Applications
Our commutator turning service is commonly used for:
Commutator skim turning before brush assembly
Commutator resurfacing for maintenance and refurbishment
Trueing and runout correction after press-fit or winding
Surface preparation to reduce brush arcing and noise
Consistency improvement for high-volume motor production
Request a Quote (12-Hour Response)
Upload your drawing or photos. We reply with price, lead time, and a clear inspection/tolerance plan.
We will never share your drawings. NDA available upon request.
WhatApps
+86 17820674273
Address
Taixing Science and Technology Park, No. 3 Taixing Road, Dongguan City, Guangdong Province
FAQ
Commutator turning is a precision machining process that removes a small amount of material to restore roundness and concentricity, producing a consistent surface finish for brush contact.
Yes. We evaluate incoming condition first (wear depth, cracks, loosened segments, remaining material). If resurfacing is feasible, we confirm the stock removal and final dimensions before machining.
Typical ovality/roundness can reach ≤ 0.015 mm when incoming condition allows. Final capability depends on datum selection, part geometry, and remaining material. We confirm feasibility at quote stage.
Yes. We provide an inspection report with key dimensions and runout checks based on the agreed plan.
Yes. If required, our service can include precision mica undercutting, edge chamfering, deburring, industrial cleaning, and anti-oxidation protective packaging.
Typically 3–5 business days for samples or small batches, and 10–15 business days for production batches after confirmation, depending on quantity and specific operations.
PDF for review is fine; STEP/DWG/IGS is preferred for accurate evaluation. Photos are helpful for refurbishment parts.
Related Resource
At XDC, we share our deep insights into commutators, manufacturing processes, and industry experience on our blog. We invite you to explore these articles to learn more about our expertise.
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