Yeah, I agree that the spray is stupid expensive....I doubted whether I needed it as well.
I have no idea whether it is necessary. I assume that the product cures to the same hardness without it. I used it to ensure that the surfaces were absolutely clean of everything and that the bond would be a really good one. Perhaps someone else on here could elaborate more on whether or not the spray is a necessity when using Loctite like products. Perhaps the Loctite website would have more info on that? I'll probably have that nearly full can of unused spray until I die...!
