BEYOND WC25-4D-SD21-WC04 U-Drill | 21mm Indexable Insert Drill (4D Depth)
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BEYOND WC25-4D-SD21-WC04
Professional 4D Indexable U-Drill | 21mm High-Precision CNC Tooling
Industrial-Grade 21mm Indexable Drilling
The BEYOND WC25-4D-SD21-WC04 is a high-rigidity indexable insert drill engineered for rapid metal removal. Featuring a 21mm cutting diameter and a 4D depth-to-diameter ratio, this tool is the definitive choice for high-speed internal cooling drilling. Optimized for heavy-duty CNC machining, it provides exceptional stability in carbon steel, alloy steel, and stainless steel.
Model Code Specification
Technical Data & Metric/Imperial Comparison
| Feature | Metric Model (mm) | Imperial Equivalent (Inch) |
|---|---|---|
| Cutting Diameter (SD) | 21.0 mm | 0.827" |
| Shank Diameter | 25.0 mm | 0.984" |
| Max Drilling Depth (4D) | 84.0 mm | 3.307" |
Recommended Cutting Parameters
Achieve optimal results in metal holemaking by following these standard guidelines:
- Cutting Speed (Vc): 120 - 200 m/min (Material dependent).
- Feed Rate (f): 0.05 - 0.15 mm/rev.
- Coolant Strategy: High-pressure internal coolant is mandatory for 21mm diameters to flush chips effectively and protect the tool body.
Premium Material & Optimized Spiral Flute
Constructed from high-performance alloy steel with specialized anti-vibration quenching, this WC04 insert holder ensures maximum rigidity. The wide spiral flute geometry is specifically engineered for "forced" chip removal, preventing chip-packing—the primary cause of tool failure in 21mm deep hole drilling. The nickel-plated body minimizes friction and prevents chip welding during high-speed operations.
WC Series U-Drill: Advantages & Considerations
- Uses WCMX / WCMT inserts with 3 usable cutting edges (Highly cost-effective).
- Stable performance on uneven or curved entry surfaces compared to SP series.
- Excellent chip breaking on low-carbon and alloy steels.
- Requires higher spindle torque and machine power.
- Surface finish may require secondary finishing for high-precision bores.
Product Q&A
A: Yes, the WC series is designed for both through-holes and blind holes with flat bottoms.
A: Yes, each 21mm U-drill body includes the correct Torx wrench and insert screws.
Verified Customer Reviews
"Excellent Stability" - Hans G. (Germany)
The 4D length works perfectly on our CNC lathe for 4140 steel.
"Best Value Drill" - Mark T. (USA)
Switched from a name brand to BEYOND. No difference in tool life!
"High Efficiency" - Hiroshi S. (Japan)
Internal coolant ports are perfectly aligned. Chips flow smoothly.
"Rugged Body" - Ricardo M. (Brazil)
Nickel coating is very durable. Using it for batch production.
"Fast Shipping" - Liam O. (UK)
Arrived in London within a week. Tool performs as described.
Pro-Tip: Choosing Drill Depth (2D to 5D)
The L/D ratio is critical for CNC tooling success:
- 2D/3D: Maximum rigidity; best for shallow holes and high-feed roughing.
- 4D (This Model): The balanced universal standard for industrial deep-hole machining.
- 5D: Specialized deep-hole drill bit. Requires extreme coolant pressure to maintain hole straightness.
Need Help With BEYOND Inserts?
Looking for a BEYOND equivalent, alternative grade, or sample catalog? Our CNC specialists have helped 50+ manufacturers in aerospace, automotive, and medical machining source the right tooling at 30–50% lower cost than OEM prices.
This BEYOND insert is in stock. 24-hour quote response. ISO 9001 certified. Ships from Hangzhou in 3–7 days.
Technical FAQ & Buying Guide
When choosing CNC cutting tools, check the full model code, dimensions, grade and selected variant before ordering. Do not rely on the product image alone.
For carbide inserts, tool holders, drills and end mills, compare the mounting dimensions, connection type and manufacturer's specifications with your holder or machine. If you are unsure, share your existing part number and machining application with us before ordering.
Check the product listing for the selling unit, pack quantity and included components. If it is unclear whether the price is per piece or per pack, or whether a tool body and inserts are sold separately, contact us before purchasing.
Select cutting speed, feed rate and depth of cut using the relevant manufacturer's recommendations for your tool model, workpiece material, machine conditions and coolant method. The same settings are not suitable for every product or application.
Our automatic quantity discount is 6% off for 2–9 items and 12% off for 10 or more items, based on the total product quantity in the cart. Other offers may not combine with this discount; check the applicable offer conditions.
According to our shipping policy, orders are typically processed and shipped within 1–3 business days after confirmation. Delivery generally takes 5–20 business days, depending on your destination and shipping method. Customs clearance or unforeseen delays may affect delivery times. A tracking number is sent by email after shipment.