If you've had to drill out a sheared shaft these can clear remnants from the hole. If the thread is damaged it shaves off the damage. As a last resort drill it larger, tap a new thread and use a larger shaft for the repair (if the assembly will allow it).

Adjustable Silver T-Handle Ratchet Tap Holder Wrench with 5pcs M3-M8 3mm-8mm Machine Screw Thread Metric Plug T-Shaped Tap
Adjustable Silver T-Handle Ratchet Tap Holder Wrench with 5pcs M3-M8 3mm-8mm Machine Screw Thread Metric Plug T-Shaped Tap
4.0
£8.89
Amazon.co.uk
Hi-Spec 20pc Metric Tap & Die Set. Complete M3 to M12 Tapping and Threading Tools with Tap Wrench Accessories
Hi-Spec 20pc Metric Tap & Die Set. Complete M3 to M12 Tapping and Threading Tools with Tap Wrench Accessories
4.0
£21.99
£16.99
Amazon.co.uk
Gunpla 6pcs Tap Drill Bits Set, Durable Titanium Coated HSS Combination Metric Thread Drilling Bits Twisted 1/4” Hex Shank Hand Machine Screw Threading Tapping Tools M3 M4 M5 M6 M8 M10
Gunpla 6pcs Tap Drill Bits Set, Durable Titanium Coated HSS Combination Metric Thread Drilling Bits Twisted 1/4” Hex Shank Hand Machine Screw Threading...
4.0
£7.63
Amazon.co.uk
Amazon price updated: 2025-08-30 22:20

Use to...

• Repair damaged internal threads.

• Clean dirty internal threads.

• Cut new internal threads.

Buying Tips

• Buy a T-handle if not included.

• Available as a kit with a matched drill bit.

• Consider a full tap, die and drill set.

Safety Tips

• Always wear eye protection.

• Consider impact protection.