Thread Repair Kits, UNF 3/8 - 1,5D

• repairing damaged internal UNF 3/8 threads with the V-COIL repair process
• workshop and maintenance repairs where the original screw size should remain usable
• component repair in housings, covers, brackets, flanges, and similar metal parts
• selection by thread size, insert length, included tools, and required inspection method

Note Confirm UNF 3/8, the insert length, and every included tool before starting the repair.

• kit structure keeps the repair workflow connected to UNF 3/8
• coordinated preparation, STI tapping, insertion, and checking steps reduce the risk of mixing tools from different sizes
• insert repair can retain the original screw size when the component condition allows controlled preparation
• existing scope of supply data lists 5 component lines for this kit

• A repair kit only works when the damaged component can be prepared correctly; replace the component or use a different repair method if alignment or remaining wall strength is not sufficient.

1. Identify the damaged thread and confirm that the kit is the correct repair size for UNF 3/8.
2. Secure the component so the preparation tool can follow the original thread axis.
3. Prepare the damaged hole with the drilling or cleaning step required by the kit workflow.
4. Cut the STI receiving thread with the included or specified repair tap.
5. Clean the hole and remove chips before the insert is installed.
6. Install the wire thread insert with the correct inserting tool until the seating position is reached.
7. Remove the tang where the selected insert system requires that step.
8. Check the repaired thread with the mating screw or inspection method used in your process.

Kit components

• 1x STI-Short Machine Taps, ForD, HSS-G, UNF 3/8 x 24 VÖLKEL 03157
• 1x Tang Break Tools, No. 13 VÖLKEL 07013
• 1x Inserting tool with locking ring, No. 13 VÖLKEL 08013
• 15x Wire thread inserts - type S - free running UNF 3/8 x 24 – 1.5 D
• 1 piece STI Twist drill 9.8 mm

• Product type: thread repair kit
• Thread repair system: V-COIL
• Thread designation: UNF 3/8
• Insert length: 1.5D
• Listed component lines: 5

When do you use a thread repair kit instead of a refill pack?

Use a kit when the repair tools and inserts must be available together for the selected thread size or size range.

Which thread does this kit address?

This kit addresses UNF 3/8. UNF identifies a Unified fine inch thread used on inch based fasteners where a finer pitch is specified.

How do you choose the correct component from the kit?

Follow the repair sequence: preparation tool first, STI tap second, insert and inserting tool third, tang or finishing tool only when the insert type requires it.

What should be checked before drilling or preparing the hole?

Check alignment to the original thread axis, remaining wall material, and whether the damaged component can be repaired without shifting the screw position.

Where can you find V-COIL thread repair technical information?

Use the Technical information V-COIL thread repair as PDF.

How do you identify replacement components when links are present?

Use the linked component article number in Scope of supply and match it to the same repair size and tool function.

What is the main risk during installation?

Misalignment during preparation or insertion can damage the new receiving thread, so the tool path must follow the original thread axis.

Where can you find the VÖLKEL thread repair catalog?

Use the VC 23 catalog as PDF.