Imperial V-Coil Thread Repair Cutter Kit Helicoil Damaged Threads 1/4 – 1/2 UNF

Regular price £213.70 GBP Sale price £213.70 GBP
In stock: 4
SKU: UN077
Professional imperial thread repair kit for commercial or occasional use

Stainless steel inserts

5 different sizes imperial inserts to choose from

V-Coil inserts provide high strength internal threads that resist the effects of both temperature and corrosion

V-Coil thread inserts are compatible with Helicoil kits as well

Imperial thread repair / Helicoil kit

Imperial UNF threads

Suitable for thread reinforcement or repair

Easy and simple to use

Imperial sizes ranging from 1/4 UNF – 1/2 UNF

5 different size helicoil in this one kit


• 1/4" UNF, 5/16” UNF, 3/8” UNF, 7/16” UNF and 1/2" UNF

Creates a strong internal thread in softer materials

Permanent repair to worn and damaged threads

Suitable for repairing damaged or stripped internal threads

Due to the narrow and exact tolerances the new thread is normally stronger


1. DRILLING – Clear the damaged thread with a standard drill – the kit includes the correct size drill
2. CHECK – Check that the thread and pitch of the tap and the bolt match
3. TAPPING – Use the special V-coil taps for cutting the holding thread into the cleared hole. It is recommended to use a suitable cutting oil
4. INSTALL THE INSERT – place insert on installation tool and position the adjustable ring so that the insert tang is centred on the tang slot. Wind the insert in with a light downward pressure until half a turn below the surface
5. TANG REMOVAL – after finishing remove the installation tool and use the tang break tool to remove the tang


• 5 different sized taps – 1/4 x 28, 5/16 x 24, 3/8 x 24, 7/16 x 20 and 1/2 x 20
• 5 different sized drills – 6.7mm, • 8.3mm, 9.8mm, 11.5mm and 13mm
• 5 x insert installation tools
• 5 x tang removal tools – the part on the insert in the centre
• 25 x 1/4 UNF inserts
• 25 x 5/16 UNF inserts
• 25 x 3/8 UNF inserts
• 10 x 7/16 UNF inserts
• 10 x 1/2 UNF inserts

Comes in a metal tin for easy storage and transportation