Combined threading and drill-bit (set of 7 pcs.) HSS-G UNF No. 8 – UNF 3/8

• Cut or restore internal threads in pre-drilled holes in maintenance work, prototyping, and controlled small batch production.
• Select the tool by the thread designation and standard stated in the product name and keep the tool square to the bore axis.
• Use cutting fluid matched to the material to reduce friction and support chip evacuation from the flutes.
• Process: manual driving or assisted driving depending on your holder and machine setup
• Use: thread cutting, re tapping, and thread cleaning depending on condition

Note Verify the workpiece preparation before you start and stop if torque increases unexpectedly.

• Controlled internal thread cutting for workshop and maintenance tasks.
• Supports clean thread start when you keep the tap aligned and use suitable lubrication.
• Fits common tapping workflows for through holes and blind holes as stated in the product name.
• Useful for repair tapping when you need manual feel and torque feedback.

• Not suitable for very hard or highly abrasive materials where carbide tooling is required.
• Not suitable for high volume production tapping where cycle time is critical.

1. Confirm the thread designation in the product name and prepare a suitable core hole for that thread system.
2. Chamfer the hole edge and remove burrs so the tap starts cleanly.
3. Secure the tap in a suitable holder and align it square to the bore axis.
4. Apply cutting fluid matched to the material and start with steady torque.
5. Advance with controlled feed and briefly back off when torque rises to clear chips.
6. Continue until the required depth is reached, then reverse out fully.
7. Clean the thread and verify fit with a matching fastener or gauge.

• 1x VÖLKEL 67293
• 1x VÖLKEL 67294
• 1x VÖLKEL 67295
• 1x VÖLKEL 67296
• 1x VÖLKEL 67297
• 1x VÖLKEL 67298

• Thread system: UNF
• Tool material: HSS-G

How do you select the correct tool variant from the product name? Match the thread designation and standard stated in the product name to your drawing or the mating fastener. Confirm whether you need an internal or external thread tool and whether the thread is left hand or right hand. What does the thread designation in the product name mean? UNF identifies Unified National Fine inch threads used where a finer pitch is typical for the same nominal diameter. How do you translate inch thread designations when planning a job? Inch to mm conversion table as PDF How do you reduce the risk of cross-threading at the start? Prepare a clean chamfer and keep the tool axis aligned with the hole or rod axis. Start with controlled torque and stop if the tool tilts or binds. How do you verify the result after threading? Use the mating part or a suitable thread gauge to confirm smooth engagement and correct fit. Clean the thread first so chips do not mask the result. Where can you find more product and application information in a catalog? VD 23 catalog as PDF