Thread inserts made of wire BaerCoil® and self-tapping thread inserts BaerFix® - Bye-bye torn-out threads

There is the repair of external threads on the one hand and the repair of internal threads on the other. Whereas for external threads, i.e. on a screw or bolt, only "re-tapping" with a cutting round die or a hexagon die nut actually works, there are considerably more options for internal threads. We therefore deal mainly with the thread repair of internal threads by means of thread inserts. The principle is always the same: The old broken thread is drilled out and extended. The thread insert then reduces it to the original thread size. BAER offers two different thread repair solutions: The thread repair with BaerCoil® wire thread inserts and the repair of the thread with the BaerFix® self-tapping thread inserts.

Thread repair with wire thread inserts from BaerCoil®

For thread repair with BaerCoil® wire thread inserts, the old thread is first removed and drilled minimally larger. For example, with M 6 threads, 6.3 mm is drilled out, which is just 0.3 mm more than the original thread.

Then a special screw tap is then used to cut the receiving thread for the thread insert. This screw tap is also called STI screw tap for “Screw Thread Inserts”. The thread for the wire thread inserts is standardized according to DIN 8140-2, so all manufacturers adhere to it. The screw tap from other manufacturers are therefore compatible with the thread inserts and the thread repair from BAER.

After the thread has been cut, the thread insert is screwed in using a special inserting tool. We have different inserting tools to choose from, so you can choose whether you want to operate the tool by machine or by hand. Our wire thread insert for thread repair is made of work-hardened stainless steel 1.4301 and is therefore very wear-resistant and high-strength. This guarantees lasting repairs for your threads.

Most wire thread inserts have a tang, which has to be broken after installation - use the tang break tool for this.

At BAER you will find all the required thread repair sets , with which you can always repair one thread size each. For professionals and more ambitious hobby screwdrivers we also offer BaerCoil® thread repair assortments where several thread sizes are always in one assortment case.

The great advantage that comes with the BaerCoil® thread repair system is primarily the very even distribution of forces that can be delivered to many threads by the wire thread insert. This ensures that the repaired thread is significantly stronger and more wear-resistant than the original thread. Due to this thread reinforcement or thread armoring, thread inserts is used today in many lightweight constructions to make threaded connections more stable and to save weight.

The advantages of BaerCoil® at a glance:

• High surface quality of the repaired thread, as it is work-hardened stainless steel
• High corrosion resistance, as A2 stainless steel (material number 1.4301)
• Repairs thread not only, but makes it stronger à thread reinforcement
• Larger contact surface with the receiving material, as the receiving thread of the thread insert is larger than the original thread
• Withstands more forces, as the forces can be better transferred to the somewhat flexible wire
• Saves the environment and resources, as repairing components is often better than replacing them
• Compatible with tools and repair systems with wire thread inserts from other manufacturers, as they are based on the same standards (e.g. DIN 8140)
• Extremely small space requirement, as the thread insert is the smallest possible size and can therefore also be used when there is little carrier material available
• The only disadvantage is the somewhat more complex installation. 4 steps are needed to repair the thread and several special tools, such as the special screw tap and the inserting tool.

BaerFix® thread repair for thread inserts with self-tapping thread inserts

The BaerFix® system for thread repair has thicker-walled thread inserts compared to the BaerCoil® wire thread inserts. Therefore, this repair system is only suitable if sufficient carrier material is available. In addition, these thread inserts cut the holding thread itself when screwed in, so they can only be used in materials with a tensile strength of up to approx. 450 N/mm². All materials above this are too strong and can only be repaired if you pre-cut the holding thread of the thread insert so that the insert no longer has to remove the entire material.

When using thread repair with BaerFix® thread inserts, the core hole is also drilled first. However, this is considerably larger, so for an M 6 thread, the core hole is drilled out at 9.3 mm.

Then the self-tapping thread insert is turned onto a special inserting tool and locked with a lock nut. In addition to the manual inserting tool with lock nuts, there are also machine inserting tools that automatically release the locking and unlocking.

The thread insert is screwed into the hole with cutting slot or cutting hole facing downwards. The lock nuts are loosened and the inserting tool is unscrewed.

The advantages of the thread repair with BaerFix®:

• Saves resources and costs as the repaired thread can be reused
• The BaerFix® system is very easy to use, as only drilling is required and then the thread insert is screwed in.
• Due to the larger external thread of the thread insert, it has more contact surface with the carrier material. The result is wear-resistant threads that are stronger than the original thread.
• Thread inserts made of case-hardened steel, with zinc plating for high-strength threads
• Can also be used for thread reduction if an incorrect thread size has been used.

However, it should be distinguished that BaerFix® self-tapping thread inserts are only suitable for thread repair threads if sufficient material is available. They require a lot of space and the simple self-tapping installation is only possible for materials up to approx. 450 N/mm². For stronger threads, the mounting thread must be pre-cut.

Available are the BaerFix® thread repair kits in single sets per thread size and as BaerFix® thread repair workshop sets with different sizes in an assortment case.

Professional thread repair with BAER

With the high-quality thread repairs BaerCoil® and BaerFix® you can prolong the life of your threads in the long term. 40 years of experience and the continuous development of our products have contributed to the excellent quality of the BAER brand. If you have any questions about BAER or our product range, please feel free to contact us via our contact form - we will advise you with the utmost professionalism and years of expertise. Your enquiry is always welcome at BAER!