To apply and remove Loctite threadlocker correctly, you need to follow several steps.

In the following article, we provide application guidelines for applying and removing threadlockers and also highlight common mistakes.

THE MOST IMPORTANT THING IN BRIEF:
  • To use threadlocker correctly, follow these steps: surface preparation, drying the threads, shaking the bottle before use, applying the threadlocker, tightening the nut/screw, and allowing it to cure.
  • How to remove Loctite threadlocker depends on whether it is a low-strength, medium-strength, or high-strength threadlocker.
  • Common mistakes when applying threadlockers include, among others: applying the wrong product, using too much adhesive, failing to prepare the surface properly or at all, not allowing sufficient curing time, repositioning an assembly, and improper disassembly.

Table of contents

How to Use Threadlocker Correctly

To use a threadlocker correctly, you must follow these steps; these are application instructions for Loctite threadlockers:

Step 1: Surface Preparation

Proper preparation of the surface to which the threadlocker is applied is crucial for the threadlocker’s performance and durability. This is because screws and nuts may have anti-corrosion coatings, for example, that were applied during the manufacturing process. These coatings must be removed using the correct cleaner. Otherwise, the curing process may be impeded.

Oil, grease, dust, and other contaminants must also be removed from screws and nuts using a suitable cleaner.

If a screw has been removed and still has hardened threadlocker on it, you must soak the screw in a solvent to reuse it. It is then cleaned mechanically, for example, with a wire brush. An internal thread contaminated with threadlocker can also be cleaned with a tap instead of a wire brush.

Properly cleaning the bolts and nuts before applying the threadlocker ensures optimal mechanical, thermal, and chemical performance of the threadlocker.

Step 2: Let the threads dry

After cleaning bolts and nuts, you must let their threads dry completely.

Care must be taken to ensure that no traces of the cleaner used remain on the surfaces to which the threadlocker is applied.

Step 3: Shake the bottle before use

Before you start applying the threadlocker, you must shake the bottle containing the product.

Step 4: Apply threadlocker

The next step is to apply the threadlocker. But how do you apply threadlocker? The threadlocker is applied only to the area where the two threaded parts are supposed to be joined together. A few drops of threadlocker are enough. You only need to apply the threadlocker to the bolt—that is, only to the external threads. You do not need to apply the product to the nut. Furthermore, you don’t need to apply the threadlocker all the way around the screw. When you screw the nut onto the screw, the adhesive will spread around the screw on its own.

So you shouldn’t apply too much threadlocker, otherwise the area to be bonded will be too filled. In addition, if there is too much adhesive, the bond will be messy and the threadlocker will run over the edges.

For a screw with a blind hole, apply the product into the blind hole until it reaches the bottom of the hole. When the screw is then screwed in, the air pocket ensures that the product is distributed throughout the thread. If you were to apply the product to the screw and then screw it into the blind hole, the air pocket would force the product out of the threads, leaving no adhesive—or far too little—on the threads.

And then there are also thread-locking adhesives that are very thin in consistency, such as Loctite 290. This thread-locking adhesive may be suitable for screws that have already been assembled, where the nut has already been screwed onto the screw. If you then apply the low-viscosity product to the protruding screw just above the nut, the adhesive is drawn into the thread gap by capillary action.

Step 5: Attach the nut to the screw or screw it into the blind hole

Next, slowly screw the nut onto the bolt until it is tight.

If you’re working with a blind hole, you need to slowly screw the bolt into the blind hole until it is securely in place.

If the screws have already been tightened, skip step 5.

Step 6: Curing

Finally, the threadlocker must cure. For most Loctite threadlockers, complete curing takes 24 hours. The curing process is anaerobic. This means that no oxygen must reach the bonded area.

To ensure that the threadlocker performs optimally, it is essential to allow it to cure completely. Otherwise, the threadlocker may not achieve its full mechanical and physical properties.

If you want to speed up the curing process, you can use an activator.

The exact curing time can be found in the technical data sheet (TDS) for the specific threadlocker. The following factors may also affect the curing time:

  • Temperature
  • Gap
  • Activity of Metals
  • Use of Activators

Removing Loctite Threadlocker

If you want to remove Loctite threadlocker, you must first determine whether it is a low-strength, medium-strength, or high-strength threadlocker. This is because the removal process varies depending on the strength of the threadlocker.

Low-strength and medium-strength threadlockers can be removed with standard hand tools.

High-strength threadlockers , on the other hand , must be heated locally to over 260 °C and then removed with hand tools while the area is still hot. It is essential to wear heat-resistant protective gloves when doing so.

Some screws that are screwed into tapped holes are at risk of breaking if they are not exposed to heat.

Be sure to check out our article“Loctite Threadlockers—Low, Medium, or High Strength.”

Common Mistakes When Applying Threadlocker

If you want to use threadlocker correctly, you should also be careful to avoid common mistakes.

Order for the wrong product

Loctite threadlockers differ, among other things, in terms of strength, temperature range, and the thread size for which they were designed. Therefore, before applying a specific threadlocker, you should carefully determine which product is best suited for your intended application.

Too much glue was used

It is essential to make sure not to use too much threadlocker—just a minimal amount. This is because excess adhesive will spread beyond the desired area and will not cure properly.

Lack of preparation or poor preparation

To ensure that the curing of the threadlocker is not impaired and that full adhesive strength is achieved, the surfaces to be bonded must be cleaned of anti-corrosion coatings, oil, grease, dust, and other contaminants before applying the threadlocker.

Failure to observe the curing time

For most Loctite threadlockers, the curing time is 24 hours. The curing time to be observed for each specific threadlocker product is specified in the corresponding technical data sheet (TDS).

Repositioning of an assembly

If an assembly to which threadlocker has already been applied is repositioned during the curing time, this can cause the threadlocker to fail. This is because rotating a fastener irreparably destroys the chemical bonds that have formed as a result of the anaerobic reaction that has already taken place during curing.

Incorrect Disassembly

Low-strength and medium-strength threadlockers can be removed using standard hand tools. However, high-strength threadlockers require localized heating (see above).

Advice on the Use of Threadlockers

The Swiss specialty wholesaler abovo has been an authorized Henkel distributor for about 20 years and, among other products, also sells Loctite threadlockers. We would be happy to advise you on the use of threadlockers.

We recommend that you contact our Henkel experts at abovo today, either by phone or email:

  • Telephone : +41 32 552 44 44
  • E-mail: info@abovo.ch

If you contact us by e-mail, we will reply as quickly as possible.

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