Thread Repair Kits, UNC 5/8 - 1,5D

• for repairing damaged or worn UNC 5/8 x 11 internal threads
• for components where the existing internal thread is stripped, worn or no longer suitable for assembly
• for reinforcing threads in materials with lower shear strength
• for creating a durable internal thread with a free-running Type S wire thread insert
• for maintenance, machine building, repair workshops, assembly and technical service work
• Process: manual or assisted drive depending on your tool holder and machine configuration
• Use: thread cutting, thread recutting and thread cleaning depending on the condition of the thread

Note Before repair, check the thread size, wall thickness and available installation depth. For UNC 5/8 x 11, stable axial guidance is important so the insert can carry load evenly after installation.

• coordinated repair configuration with STI tap, inserting tool and matching wire thread inserts
• 10 included inserts allow several repairs in the same UNC size
• manual inserting tool with locking ring supports controlled insert installation
• Type S is free running and suitable for standard screw connections without locking effect
• stainless steel wire thread inserts help restore damaged internal threads in suitable components
• useful for larger UNC connections where replacing the component should be avoided or postponed

• The repair requires clean preparation of the receiving thread and controlled insert depth; suitable additional tools and system options are available in the VÖLKEL thread repair range.

1. Inspect the damaged internal thread and assess whether the component structure allows a wire thread insert repair.
2. Secure the component and keep the repair operation aligned with the existing thread axis.
3. Prepare the damaged thread area for the STI receiving thread according to the V-COIL repair process.
4. Cut the STI receiving thread using the included STI tap.
5. Remove chips and residues completely from the receiving thread.
6. Place the wire thread insert in the inserting tool and guide it straight to the prepared thread.
7. Turn the insert in evenly until the intended installation position is reached.
8. Remove the tang according to the system procedure using a suitable tool.
9. Check the thread run with a matching screw or an appropriate inspection method.

• 1x STI Short Machine Tap ISO 529 Form D HSS-G for UNC 5/8 x 11 VÖLKEL 03113
• 1x Manual Inserting Tool with locking ring No. 18 VÖLKEL 08018
• 10x V-COIL wire thread inserts, free running Type S, UNC 5/8 x 11, 1.5 D VÖLKEL 08314

• Product class: thread repair
• Product type: V-COIL thread repair kit
• Thread system: UNC
• Nominal size: UNC 5/8 x 11
• Insert length: 1.5D
• Insert type: Type S, free running
• Insert standard reference: DIN 8140
• Insert tolerance: ISO 2 (6H)
• Insert material: stainless steel
• Tap: STI short machine tap ISO 529 Form D HSS-G
• Inserting tool: manual inserting tool with locking ring No. 18
• Repair principle: STI receiving thread with wire thread insert

What is this V-COIL repair kit used for?
It is used to repair damaged UNC 5/8 x 11 internal threads. The wire thread insert restores a load-bearing internal thread function inside the prepared STI receiving thread.

What should be checked before selecting the kit?
The UNC 5/8 x 11 thread designation, 1.5D insert length and the available material around the damaged thread should match the repair task.

Why is an STI tap required?
The STI tap creates the special receiving thread for the wire thread insert. The repair principle is explained in more detail here: technical information V-COIL Thread Repair as PDF.

What is the purpose of inserting tool No. 18?
The inserting tool guides the wire thread insert into the prepared STI thread. The locking ring supports controlled handling during manual installation.

What does free-running Type S mean?
Type S means the insert produces a normal free-running internal thread without an additional screw-locking effect.

Where can I find technical details on wire thread inserts?
Information on wire thread inserts according to DIN 8140 is available here: technical information Wire Thread Inserts DIN 8140 as PDF.

Is this kit suitable for external threads?
No. This V-COIL repair principle is intended for internal threads. External threads are not repaired directly with this kit.

Where can I find further V-COIL system information?
An overview of V-COIL repair systems, inserts and accessories is available in the VC 23 catalogue as PDF.