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OSG Carbide 4 Flute End Mill Ball Nose - Regular Length Centre Cutting For General Applications - 3.5mm
| Cutter Diameter | 3.5 |
| Number of Flutes | 4 |
| Flute Length | 12 |
| Overall Length | 51 |
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Description
The OSG Carbide 4-Flute End Mill with Ball Nose (Regular Length, 3.5mm diameter) is a versatile cutting tool designed for general machining tasks. Its four-flute carbide construction and ball-nose profile enable precise contouring, profiling, and 3D machining with consistent results and smooth finishes.
With center-cutting capability and a regular-length body, this end mill is ready for a variety of setups and materials, making it a dependable choice for machinists across multiple industries—from aerospace and automotive to general manufacturing.
- Four-flute carbide design: Delivers efficient material removal and stable cutting for reliable, repeatable results in everyday milling tasks.
- Ball nose geometry for 3D detail: Creates smooth, accurate contours and fine surface finishes on complex shapes and profiles.
- Regular length, center-cutting versatility: Supports plunging, profiling, and contouring in a wide range of machining scenarios, expanding your setup options.
This end mill combines durable carbide with a precise geometry to help you finish parts faster, with consistent quality and fewer tool changes. Whether you're shaping soft plastics, aluminum, or other general-purpose materials, you can rely on steady performance and durable construction to deliver high-quality results in day-to-day manufacturing tasks.
Part Numbers
- Protool Part Number
- OSG-404-1378-BN
- Brand
- OSG
- Category
- End Mill
Delivery
Free UK mainland delivery on orders over £50 ex VAT. In-stock items ordered before 4:30pm are dispatched the same working day. Full delivery information.
Returns
14-day returns on unused stock items in original packaging. Special-order and bespoke tooling is non-returnable. Read our returns policy.
Technical Support
Over 30 years of machining experience behind the counter. Call 01732 887334, Mon–Thurs 8:30–17:30, Fri 8:30–16:30.
Trade Accounts
Credit accounts, contract pricing and scheduled call-off orders available for trade customers. Apply for an account.
What time are Protool open?
We are open Monday to Friday between 8:30am and 5pm.
Do you offer Free Next Day delivery?
Yes! We offer Free Next Day delivery via Royal Mail Tracked 24 on all orders over £50 ex VAT*. We also offer Free DPD Local Next Day delivery on all orders over £100 ex VAT*.
We also offer the following:
- Royal Mail Tracked 24 — £5.90 (FREE on orders over £50 ex VAT*). Order before 4:30pm for next day delivery. No signature required.
- DPD Local Next Day — £8.00 (FREE on orders over £100 ex VAT*). Standard next day delivery to UK mainland addresses.
- Royal Mail Special Delivery — £12.50. Guaranteed delivery before 1pm the next working day.
- DPD Saturday Delivery — £25.00. Must be ordered on Friday before 4pm. Pre-12pm delivery.
For delivery to Scottish Highlands & Islands, Northern Ireland, Republic of Ireland, or overseas locations, additional charges apply. Please see our delivery page for full details, or call us on 01732 887 334.
*T's & C's and exclusions apply. Please see our delivery page for more information on all our services.
Full Range: OSG Carbide 4 Flute End Mill Ball Nose - Regular Length Centre Cutting For General Applications
View full collection →You are viewing OSG-404-1378-BN. Click any other SKU to view its full details.
| Product SKU | Cutter Diameter | Number of Flutes | Flute Length | Overall Length | Shank Diameter | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|
| OSG-404-0394-BN | 1 | 4 | 3 | 39 | 3 | £19.59 | In Stock | |
| OSG-404-0591-BN | 1.5 | 4 | 5 | 39 | 3 | £12.65 | In Stock | |
| OSG-404-0787-BN | 2 | 4 | 7 | 39 | 3 | £13.89 | In Stock | |
| OSG-404-0984-BN | 2.5 | 4 | 8 | 39 | 3 | £12.65 | In Stock | |
| OSG-404-1181-BN | 3 | 4 | 10 | 39 | 3 | £12.66 | In Stock | |
| OSG-404-1378-BN Viewing | 3.5 | 4 | 12 | 51 | 4 | £17.41 | In Stock | |
| OSG-404-1575-BN | 4 | 4 | 14 | 51 | 4 | £18.21 | In Stock | |
| OSG-404-1772-BN | 4.5 | 4 | 14 | 51 | 5 | £19.24 | In Stock | |
| OSG-404-1968-BN | 5 | 4 | 16 | 51 | 5 | £19.24 | In Stock | |
| OSG-404-2362-BN | 6 | 4 | 19 | 64 | 6 | £23.02 | In Stock | |
| OSG-404-2756-BN | 7 | 4 | 19 | 64 | 8 | £27.44 | In Stock | |
| OSG-404-3150-BN | 8 | 4 | 21 | 64 | 8 | £26.80 | In Stock | |
| OSG-404-3543-BN | 9 | 4 | 22 | 70 | 10 | £30.71 | In Stock | |
| OSG-404-3937-BN | 10 | 4 | 25 | 70 | 10 | £36.03 | In Stock | |
| OSG-404-4331-BN | 11 | 4 | 25 | 70 | 11 | £49.39 | In Stock | |
| OSG-404-4724-BN | 12 | 4 | 25 | 76 | 12 | £59.38 | In Stock | |
| OSG-404-5512-BN | 14 | 4 | 30 | 89 | 14 | £83.30 | In Stock | |
| OSG-404-6299-BN | 16 | 4 | 32 | 89 | 16 | £114.02 | In Stock | |
| OSG-404-7087-BN | 18 | 4 | 35 | 102 | 18 | £147.22 | In Stock | |
| OSG-404-7874-BN | 20 | 4 | 38 | 102 | 20 | £167.32 | In Stock | |
| OSG-404-8661-BN | 22 | 4 | 38 | 102 | 22 | £285.14 | 1-2 days | |
| OSG-404-9843-BN | 25 | 4 | 38 | 102 | 25 | £309.40 | In Stock |
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