Thread Repair Kits, UNC No. 4 x 40

• Restore UNC No. 4 × 40 threads easily and permanently
• Reinforce threads in materials with low shear strength
• Create strong, corrosion-resistant internal threads
• Perfect for metals, plastics and aluminum components
• Delivered in a compact, durable plastic case – always ready to use

Your benefit: a fast, durable repair without reworking the component.

1. Preparation: Clean the damaged thread and pre-drill it with the 3.1 mm twist drill.
2. Tapping: Cut the new STI thread with the HSS-G tap UNC No. 4 × 40 using cutting oil.
3. Inserting: Screw in the stainless steel insert using the inserting tool until it sits flush.
4. Breaking the tang: Use the tang break tool to remove the driving tang.
5. Check: Test the repaired thread with a suitable screw.

• Brand: V-COIL
• Nominal Size: UNC No. 4 × 40
• Repair Length: 1.5D
• Material: Stainless Steel
• Packaging: Plastic Case
• EAN: 4022835041016
• Article Number: 04101

• 1× STI Short Machine Tap, HSS-G, UNC No. 4 × 40 (03101)
• 1× Tang Break Tool, No. 4 (07004)
• 1× Inserting Tool with Locking Ring, No. 4 (08004)
• 20× Wire Thread Inserts – Type S – Free Running UNC No. 4 × 40 – 1.5 D (08301)
• 1× STI Twist Drill 3.1 mm (00031)

Can I use this kit for aluminum?
Yes, the stainless steel inserts are perfect for soft materials like aluminum or plastic.

What does 1.5D mean?
The insert length is 1.5 times the nominal thread diameter, ensuring high load capacity.

Is the drill included?
Yes, the matching 3.1 mm STI twist drill is included in the kit.

Do I need any special tools?
No, everything required is included in the set – you can perform the repair manually.

How long will the repair last?
Properly installed inserts provide a permanent and wear-resistant repair.

Are other sizes available?
Yes, V-COIL offers kits for all common UNC and UNF thread sizes.