Thread Repair Kits, BSW 1/2 - 1,5D

• Restoring stripped, rusted or mechanically damaged BSW 1/2" × 12 internal threads
• Reinforcing threads in materials with low shear strength such as cast alloys or softer steels
• Recovering components that would otherwise be scrapped
• Creating strong, durable internal threads in repairs or new production
• Ideal for maintenance teams, workshops, service technicians and small batch repairs
• Includes stainless steel wire thread inserts according to DIN 8140, ISO 2 (6H), type S – free running

• All essential tools and inserts combined in one compact case
• Compatible with the entire V-COIL system and available in many standard and special dimensions
• Designed for hand use — perfect for mobile work and workshop repairs
• Significantly increased thread load capacity thanks to stainless steel inserts
• High resistance to heat, corrosion and mechanical stress
• Cost savings through refurbishment instead of part replacement
• Organised and durable plastic case ensures safe storage and easy transport

1. Clean the damaged thread: Remove dirt, corrosion, chips and loose residue thoroughly.
2. Prepare the core hole: Use the included 13 mm STI twist drill to create the correct core diameter. Use cutting oil or coolant.
3. Cut the STI thread: Create the STI thread using the STI-Short Machine Tap, Form D, HSS-G, BSW 1/2" × 12, ensuring a straight alignment.
4. Prepare the insert: Place a wire thread insert onto the inserting tool with locking ring, No. 15 and adjust the insertion depth.
5. Install the insert: Screw the insert into the STI thread until it is flush or slightly below the surface.
6. Break the tang: Use the Tang Break Tool No. 15 to snap off the installation tang cleanly.
7. Check the function: Test the repaired thread with a suitable BSW 1/2" × 12 bolt to confirm smooth engagement.

For more details, see the Technical Information V-COIL Thread Repair (PDF) .

• Repair System: V-COIL Thread Repair
• Thread Type: BSW – British Standard Whitworth
• Nominal Size: BSW 1/2" × 12
• Repair Length: 1.5D
• Thread Inserts: Stainless steel wire inserts, Type S – free running
• Insert Standard: DIN 8140, ISO 2 (6H)
• Tap: STI-Short Machine Tap, Form D, HSS-G, BSW 1/2" × 12
• Drill: STI twist drill 13 mm
• Tang Break Tool: Size No. 15
• Inserting Tool: Manual inserting tool with locking ring, No. 15
• Packaging: Plastic case
• EAN: 4022835041474
• Article Number: 04147

• 1× STI-Short Machine Tap, Form D, HSS-G, BSW 1/2 × 12 (03207)
• 1× Tang Break Tool No. 15 (07015)
• 1× Inserting tool with locking ring, No. 15 (08015)
• 10× Wire Thread Inserts – Type S – Free Running – BSW 1/2 × 12 – 1.5D (08347)
• 1× STI Twist Drill 13 mm (00130)

Refill packs with additional wire thread inserts are available separately.

Where is BSW 1/2" × 12 commonly used?
This traditional Whitworth dimension is found in classic machinery, British equipment, older installations and restoration work.

Is this kit suitable for mobile service use?
Yes — it is compact, hand-operated and ideal for on-site repairs.

Does the repaired thread become stronger?
In many cases, the stainless steel inserts provide significantly higher load capacity than the original base material.

Do I need special machines?
A standard tap wrench or suitable holder is sufficient, as long as alignment and lubrication are correct.

Are V-COIL kits available for other BSW sizes?
Yes — V-COIL offers a wide selection of repair kits and refill packs for BSW, BSF, metric and other thread standards.