Thread Repair Kits, UNC 1.1/4 - 1,5D

• Repairing damaged internal threads with a coordinated sequence of drilling, STI tapping, insert installation and finishing
• Reinforcing worn or weak receiving threads in service parts, housings and repeatedly assembled joints
• Using one matched repair set when you need process consistency for the stated thread designation
• Process: manual driving or assisted driving depending on your holder and machine setup
• Use: thread cutting, re tapping, and thread cleaning depending on condition

Note Select the product by thread designation, workpiece condition and the holder concept used in your process.

• Matched repair logic supports repeatable restoration of an existing thread designation
• Insert based repair can improve service life of the receiving thread in repeated assembly work
• Suitable for maintenance, overhaul and workshop repairs where part replacement is undesirable
• Clear assignment between preparation, tapping and insert installation reduces handling errors

• The process depends on the correct repair sequence and is not suitable when the parent material is cracked or too thin for the repair concept.
• It is a repair system and not the fastest choice when you only need a one time emergency fix without the full preparation steps.

1. Secure the part and identify the damaged thread so that the repair axis is clearly accessible.
2. Prepare the hole with the matched drill from the kit and remove loose chips from the bore.
3. Cut the receiving thread with the STI tap while keeping the tool aligned to the axis.
4. Clean the prepared receiving thread and check that the entry is free from debris.
5. Load the wire insert onto the inserting tool and start it square to the prepared thread.
6. Drive the insert until it sits at the intended depth in the receiving thread.
7. Remove the tang where required and check the repaired thread with the intended fastener or inspection method.

• 1x STI-Taps, set of 2 pcs., HSS-G, UNC 1.1/4'' x 7 VÖLKEL 03118
• 1x Inserting tool with Hexagon Drive, UNC 1.1/4 x 7.0 VÖLKEL 08051
• 10x Wire thread inserts - type S - free running UNC 1.1/4'' x 7 – 1.5

• Product type: Thread repair kit
• Thread system: UNC
• Standard: DIN 8140, ISO 2
• Form: Type S
• Tool material or finish: HSS-G
• Drive or handling concept: hexagon drive
• Tolerance marking: tolerance ISO 2 (6H
• Packaging concept: Coordinated repair kit in case

What do you use Thread Repair Kits, UNC 1.1/4 - 1,5D for?

You use this product when an internal thread must be restored, reinforced or prepared within a wire thread insert repair process. The exact role depends on whether the product is the kit, the insert, the STI tool or the installation accessory.

Where can you find more technical background?

For additional technical background, see Technical information V-COIL thread repair as PDF.

Why is a matched repair kit useful?

A matched kit keeps the repair sequence coordinated, which helps you avoid mismatches between the drill, the receiving thread and the insert installation step.

Where can you find one more related technical reference?

For a second related reference, see Technical information wire thread inserts DIN 8140 as PDF.

How do you identify the correct UNC execution?

UNC denotes Unified National Coarse, an inch based thread series used for general fastening where robust engagement and service friendly assembly are important.

Where can you find the catalog entry for this product group?

For catalog level orientation, see VC 23 catalog as PDF.

What should you check before assembly after repair?

Check that the repaired thread is clean, the insert sits correctly when applicable and the mating fastener engages smoothly without cross threading.