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Dormer A777 HSCo Cobalt Heavy-Duty Jobber Drills Metric - 3.50mm

Dormer  |  SKU: DOR350COB  |  Barcode: 7320760375020

Regular price £6.74
(£8.09 inc VAT)
Shipping calculated at checkout.

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All orders include tracking information, which will be emailed to you once your order is dispatched.

UK Mainland

  • Standard Delivery: Expected delivery within 3–5 working days.
  • Next Working Day Delivery: Available on orders placed before 4 pm.

Other Locations

  • Republic of Ireland: Expected delivery within 3–5 working days.
  • Channel Islands: Expected delivery within 3–5 working days.
  • Isle of Man: Expected delivery within 3–5 working days.
  • Scottish Highlands: Expected delivery within 3–5 working days.

Larger Items

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Please Note:

  • For deliveries outside the UK mainland (excluding Ireland), any import duties, taxes, and handling fees are the customer's responsibility. Confirm these charges with your local customs office before placing an order.
  • Batteries (unless part of a kit) and gas canisters cannot be shipped outside the UK mainland.
  • Delivery times for restricted or oversized items may be longer due to courier limitations. Contact us for specific estimates.

30 Day Money Back Guarantee

30 Day Money Back Guarantee

We hope that you won’t need to return anything to TCD, but if you do, we aim to make the process quick, easy and efficient, so you can exchange or refund your purchase with confidence.
Here are some helpful points to make your returns/exchange a smooth process, please note your statutory rights are not affected by this guidance:

  • Contact us via email sales@tradecounterdirect.com with your order details and reason for the return, we will check the items were purchased in the last 30 days
  • An exchange can then be made or a refund issued against the original method of payment

We are also able to accept returns by post to our warehouse, but unfortunately, we are not able to arrange or pay for postage, and this would be at your own expense.

The address to return to is:

Trade Counter Direct - Returns, Loribon House, Yalberton Industrial Estate, Paignton, Devon, TQ4 7QR.

Original packaging and order details must be included. Our terms exclude the collection of unwanted goods.

Description

Dormer A777 HSCo Cobalt Heavy-Duty Jobber Drill Bit 3.50 mm

The Dormer A777 HSCo Cobalt Heavy-Duty Jobber Drill Bit, available at Trade Counter Direct, is engineered for demanding drilling applications where increased heat resistance and durability are essential. This 3.50 mm metric cobalt drill bit is specifically designed for use on high tensile and tough materials, making it ideal for industries such as aerospace where precision and reliability are paramount.

Manufactured from high-speed cobalt steel (HSCo) and featuring a bronze surface treatment, the Dormer A777 delivers superior performance and longevity. Its advanced flute geometry and split point design ensure efficient drilling, reduced wandering, and optimal chip removal, even in the most challenging materials.

Features

  • Manufactured from HSCo cobalt steel for enhanced heat and wear resistance
  • Heavy-duty design suitable for high tensile and tough materials
  • 135° split point geometry minimises wandering and improves accuracy
  • Standard helix with right-hand spiral and thick web for strength and stability
  • Bronze surface treatment for reduced friction and improved durability
  • Compliant with DIN 338 RN, BS328, and ISO 235 standards
  • Optimised for aerospace and other demanding industrial applications

Specifications

SKU DOR350COB
Range/Series Dormer A777
Tip Diameter 3.50 mm
Working Length 39 mm
Overall Length 70 mm
Material HSCo Cobalt steel
Surface Treatment Bronze
Flute Geometry Standard Helix, Right hand spiral, Thick Web
Point Angle 0.30 mm – 0.95 mm: 118° Conical point
1.00 mm – 1.40 mm: 135° 4 facet point
1.50 mm and above: 135° split point (NAS 907 Aerospace Specification type P3 Point)
Standards DIN 338 RN / BS328 / ISO 235
Manufacturer Part No A7773.5