That is certainly one of the most common questions we get – whether liquid threadlocker can be applied in the case of blind holes. And the answer is: yes. There is no reason why the method would not work on blind holes same as it does everywhere else. Of course, there are certain steps to be observed.
Both parts should be cleaned with Loctite SF 7070 and a bit of time allowed for it to evaporate. It’s recommendable to use the activator for blind holes. Now, the product is called Loctite SF 7649 and in some parts of the world you’ll find it called a “primer” and packed in a bottle with a brush on cap, while in the other parts we’ll call it an activator and you’ll find it in a spray pack. It’s the same product and both versions are applicable, no worries.
After applying the activator / primer, you select your Loctite threadlocker based on the same principles as you always would – which level of strength do you need and how often do you plan to be dismantling the assembly being the main guidelines. Apply the product on both – male and female threads and tighten the bolt. Nothing more to it.