These Standard Metric Kits are ideal for repairing threads of existing fasteners. All kit sizes up to 5/8in./M16 come with 30 inserts (10-1D, 10-1.5D, 10-2D). M10 x 1.5 to M24 x 3.0 no drill bits supplied. Equipped with an inserting tool, tang remover and tap, these kits are an ideal way of ensuring you have the correct tools to hand to repair fastener threads when necessary. Supplied in a plastic carry case. Our helicoils are available as individual coil inserts or as a kit. The kits contain everything needed to install a Helicoil, including the inserts themselves, a drill bit and a tap, an inserting tool and a tang break off tool. The simplest of these and maybe most well known, is the HeliCoil insert which looks like a spring but once installed creates a new thread within a thread. The concept is simple enough. Imagine a male thread on a screw or bolt is like a spring wrapped around a smooth bar and a female thread, a spring inserted into a smooth bore. When a thread gets stripped, it’s as if that spring is being removed and in some cases, that’s exactly what it looks like. It’s not uncommon for a stud to pull out of an alloy casting with the aluminium thread still fitting neatly and yes, a little annoyingly, into its spiral grooves, just like a spring. HELICOIL® thread inserts are designed to evenly distribute loads across the screw for even distribution of stress

Metric Helicoils | Recoils | Thread Repair Inserts - Bolts

Metric is the most common thread type in production today. Usually specified as M then a number x another number. This signifies the thread diameter and the length of the fastener. A Helicoil is essentially a free-running, stainless steel wire coil that is inserted into a hole with a thread that has been specially tapped to accept it. It is used to create a standard-sized, internal screw thread within the existing hole. Helicoils come in a range of different metric thread sizes. Helicoils, sometimes called recoils or thread repair inserts, are precision inserts that are most commonly used to repair damaged or worn threads. They can also be used to create strong new threads. If done correctly, a HeliCoil is a strong repair and the only real thing to be careful of is that the fresh hole which takes the insert is drilled clean and square. That doesn’t mean to say it can’t be a hand-held job as long as it’s done carefully. The first time I ever did it was to replace a couple of sump bolt threads in an MG TC engine which was still in the car. The threads were in poor shape through old age and, probably, not the greatest quality post-war casting. Fixings on XPAG engines are a weird concoction of metric fine with BSF heads. However from memory, the bolts in question were 1.0mm metric fine and getting HeliCoil kits for them was no problem. I’ve done something similar recently and with equal success on the chassis of my Ford Sierra RS Cosworth and I’ll cover that in the next column.