Anaerobic Adhesive Activators (Loctite/permabond sealants and thread lockers)

[noema]

I am a little puzzled about the use of activators with thread sealants and thread lockers (anaerobic adhesives). They only cure without oxygen and under the influence of metal ions. Many metals in aviation are not very active in that regard. The Loctite guide lists them as required for aluminum, stainless, cadmium but nobody seems to mention them in the aviation literature/forums/etc (e.g. vans forum). At least I could not find any. I also talked to a few APs and they generally don't use activators or don't think they are important.

So what's the deal? Are these adhesives completely out of spec when used without an activator on cadmium screws and aluminum fittings? Or are they just very slow curing?

The permabond guide seems to suggest the latter.

https://www.permabond.com/resource-center/curing-anaerobic-adhesive/

I would just follow the Loctite guide and be done with it but the exact type of activator is not even readily available here in Austria. I would either have to resort to a private sale on ebay or go to a different brand (and research all this info all over again).

Just looking for some opinions and anecdotal data points. In the end I will probably just have to do a series of tests and measure.

[Viking]

I’ve been using Loctite on various fasteners for 25+ years and I’ve never once used an activator. I’m inclined to think that the activator would speed up cure time more than increase product performance, but it may do both. In any case, I’ve been satisfied with the results of my loctite use without any activator, so I probably won’t change my procedure now. I may buy some activator and do a test, just for science. I’ll post results if I do.

[noema]

Thanks for letting me know.