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Precision Grinding Services for Custom Metal Parts
Sundi MFG provides high-precision surface, profile, and cylindrical grinding services for custom metal components, tooling parts, and ultra-hard alloys. We deliver tight dimensional control, superior surface finishes, and strict repeatability for both small batches and high-volume production.
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Surface, Profile & Cylindrical Grinding
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Specializing in Tungsten Carbide & Tool Steels
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Precision Tolerances Down to ±0.002mm
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Mirror-Like Finishes & Chip-Free Edges
- Quote in 8h
- 7-15 Days Lead Time
- STEP / DXF / IGES Accepted
- Strictly Confidential (NDA Supported)
Precision Grinding Demands Strict Process Control
Custom components become challenging when conventional turning or milling cannot achieve the required micro-level flatness, precise parallelism, or when processing fully hardened tool steels and tungsten carbide.
At Sundi MFG, we don’t just turn on a grinder. Before production starts, we thoroughly evaluate the material hardness, required tolerances, grinding wheel selection, and coolant strategy to prevent heat distortion and surface micro-cracking.
To meet strict dimensional requirements, we integrate Surface Grinding, Profile Grinding, and Cylindrical Grinding. When necessary, we combine these with our in-house CNC and EDM capabilities to deliver flawless cutting edges and consistent quality.
Grinding Capabilities
At Sundi MFG, we provide a complete range of precision grinding capabilities to support custom tooling components, carbide wear parts, hardened steel dies, and complex metal fixtures. From achieving absolute flatness via surface grinding to crafting intricate micro-contours through Optical Profile Grinding (PG), our grinding processes ensure strict dimensional tolerances, mirror-like surface finishes, and flawless cutting edges for both prototypes and repeat production.
Optical Profile Grinding (PG)
Machining complex profiles and sharp, chip-free corners on tungsten carbide with absolute contour accuracy.
Surface Grinding
Delivering micro-level flatness and strict parallelism for die blocks, stripper plates, and hardened steels.
Cylindrical Grinding
Precision OD grinding for pins and punches, ensuring exceptional concentricity and tight diameter tolerances.
Jig Grinding
High-precision hole and internal contour grinding to ensure exact positional accuracy for complex die sets.
Centerless Grinding
High-efficiency volume grinding for pins, ensuring tight diameter consistency and excellent roundness.
ID Grinding
Precision bore grinding for guide bushings, achieving exact internal tolerances and smooth finishes.
5-Axis Grinding
Multi-axis grinding for complex 3D geometries and custom tooling with a single setup.
Typical Ground Components & Applications
Precision grinding is essential for achieving critical tolerances and mirror-like surface finishes on hardened metals. At Sundi MFG, we specialize in grinding ultra-hard materials and complex geometries that conventional turning or milling cannot handle. If your project requires specialty ground components not listed below, please contact our engineering team.
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Stamping Die Inserts & Punches
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Semiconductor Trim & Form Spares
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Custom Mold & Die Components
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Precision Shafts, Pins & Bushings
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Custom Cutting Tools & Industrial Blades
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Non-Standard Automation Components
Achieving Tight Tolerances in Precision Grinding
In high-precision tooling and semiconductor packaging, standard machining tolerances are often not enough. At Sundi MFG, our advanced grinding processes are dedicated to achieving the final critical dimensions of your most demanding components. We routinely hold dimensional tolerances down to ±0.002 mm and deliver mirror-like surface finishes, ensuring perfect assembly fit, precise die clearance, and extended tool life.
| Dimension / Feature | Typical Tolerances (Metric) | Typical Tolerances (Imperial) |
|---|---|---|
| Length | ± 0.002 mm | ± 0.00008 inches |
| Width | ± 0.002 mm | ± 0.00008 inches |
| Height/Thickness | ± 0.002 mm | ± 0.00008 inches |
| Diameter (for cylindrical parts) | ± 0.002 mm | ± 0.00008 inches |
| Flatness | 0.002 mm per 100 mm | 0.00008 inches per 4 inches |
| Parallelism | 0.002 mm per 100 mm | 0.00008 inches per 4 inches |
| Surface Finish | 8-16 microinches (0.2-0.4 micrometers) RA | Same as Metric |
Materials Engineered for Precision Grinding
From fully hardened tool steels to ultra-hard tungsten carbide, we utilize specialized abrasive wheels and strict coolant strategies to achieve exact tolerances and flawless finishes on the most demanding materials.
Tungsten Carbide
PCBN & CBN (Cubic Boron Nitride)
Hardened Tool Steels (SKD, D2, H13)
High-Speed Steel (HSS / ASP Series)
Hardened Stainless Steel (400 Series, 17-4 PH)
Inconel & Exotic Alloys
Scalable Precision Grinding Capacity
Equipped with a comprehensive lineup of advanced optical profile, surface, and cylindrical grinders, our facility supports custom tooling prototypes, small batches, and high-volume repeat production while keeping micro-level machining quality consistent across every batch.
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Optical Profile & Surface Grinding
Housing advanced Amada optical profile grinders (PG) and precision surface grinders to deliver complex carbide contours, sharp internal corners, and absolute flatness on die components.
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Cylindrical & Jig Grinding
Equipped with specialized cylindrical and jig grinding centers to achieve exceptional concentricity on precision punches, shafts, and exact positional accuracy for internal cavities.
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Rigorous CMM Inspection
Guaranteeing extreme precision and zero-defect delivery using industry-leading Zeiss Bridge CMMs and high-resolution Nikon Profile Projectors.
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ISO 9001:2015 Certified
Ensuring strict adherence to international quality management standards with fully documented, traceable manufacturing procedures at every stage.
Why We Provide Engineer-Reviewed Quotes
EDM pricing depends on material, thickness, tolerance, surface finish, hole size, machining path, and part complexity. That is why we do not rely on automatic online pricing. Every drawing is reviewed by our engineering team before quotation, so we can provide a more accurate price, realistic lead time, and suitable machining plan.
Our Ordering Process
We are a direct-to-factory manufacturer, not a brokered quote platform. Every component is engineered, machined, and inspected in-house at Sundi. This ensures complete control over technical precision, production lead times, and data security from your initial drawing to final delivery.
Send RFQ
Submit your 2D/3D CAD models and technical specifications via our secure online form or direct email.
Review & Quote
Our technical team evaluates your drawings for manufacturability and provides a detailed, data-driven quotation within 12 hours.
Confirm Order
Finalize technical parameters, confirm tolerances, and lock in the production schedule prior to contract sign-off.
Production
CAM programming is executed, and production begins across our specialized CNC, EDM, or stamping lines.
Quality Inspection
In-process dimensional checks and a comprehensive final inspection ensure all parts meet specified tolerances before leaving the floor.
Packaging & Shipping
Components are meticulously packed using dedicated protective materials to prevent transit damage and shipped globally.
Precision Grinding Services FAQs
What drawing formats do you accept?
For the most accurate quotation, please provide 3D CAD files (STEP, IGES, SolidWorks) to evaluate complex geometries, along with 2D drawings (PDF, DWG, DXF) clearly calling out specific grinding tolerances, surface finish requirements (e.g., Ra values), and material hardness.
What is the maximum material hardness you can grind?
We specialize in machining ultra-hard materials. Utilizing advanced diamond and CBN grinding wheels, we routinely process fully hardened tool steels (HRC 60+), Tungsten Carbide, and even custom PCBN/PCD inserts, ensuring efficient material removal without causing heat distortion or metallurgical damage.
What dimensional tolerances can your grinding process achieve?
Depending on the material and specific part geometry, our advanced surface grinding and optical profile grinding (PG) centers can hold critical dimensional tolerances down to ±0.002mm. We ensure exact parallelism, flatness, and perfect die clearances for your high-precision tooling.
Do you support small batch or single-piece custom grinding?
Yes, we have no strict Minimum Order Quantity (MOQ). We support everything from single-piece engineering prototypes to low-volume replacement parts for semiconductor trim and form dies and industrial cutting tools.
What information is needed for a fast grinding quote?
To provide a fast and accurate quote within 8 hours, please send your drawings along with the desired material grade, required heat treatment/hardness, batch quantity, and any specific surface coating requirements.
Do you provide quality inspection reports before shipping?
Absolutely. Every ground component undergoes rigorous inspection using our in-house Zeiss Bridge CMMs and Nikon Profile Projectors. We can provide full dimensional inspection reports and material certifications upon request to guarantee zero-defect delivery.
