Thread Repair: Repair

The thread repair process involves a solid, thin walled, self-locking, carbon steel, bushing type insert. During the insert installation process, the installation driver tool cold-rolls the bottom internal threads and expands the bottom external threads of the insert into the base material. This action mechanically locks the insert into place.

Fig 1: View Of J 42385-400 Tool Kit

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The drill bit and counter bore tool from the tool kit J-42385-700:  kit and J-42385-2000:  insert kit is designed for use with either a suitable tap wrench or drill motor. Limited access and larger hole repair may process better using a tap wrench. An extension from kit J-43965:  extension kit may also be necessary to drive the thread repair tooling dependent on access to the hole being repaired. Use only a tap wrench when tapping the hole and during installation of the insert.

Fig 2: Drilled Hole Centerline

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It is critical that the drilling, counterboring and tapping of the hole to be repaired follows the same centerline as the original hole.

Fig 3: Identifying Proper Drilling Angle

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During the drilling and tapping of the hole being repaired ensure the tooling is consistently machining perpendicular to the surface of the base material.

Fig 4: View Of Tapping Guide

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If the threaded hole being repaired has a base surface perpendicular to the hole centerline, tapping guides are available to aid in tapping the hole.