I used Sikaflex 221, it is absolutely the stickiest stuff I've ever used and nothing will budge it.

Avoid the stuff you can get from Screwfix, it's part adhesive part filler rather than full on adhesive.

 

Why not ask Sikaflex? I did and received a most comprehensive answer as to which of their products would be best for the purpose.A:

Cheers, Tony.T:

 

I have always been an advocate for Tigerseal. Is Silkaflex as good or does it supercede Tigerseal? Answer on a postcard please

 

I've just attached a awning rail to my roof with tiger seal, Cant see it coming off anytime soon T:

 

Thanks fellas!

 

http://www.everbuild.co.uk/SikaFlex-EBT

 

That's the stuff Screwfix sell, it's part adhesive and part filler so not as strong as 221.

 

Is 221 Silkaflex over paintable?

 

This is like those Advil adverts ... this box is specially developed for aching joints, this one for headaches, that one for period pains, that one for lower back pain ... when they're all exactly the same product.
The marketing scum-bags have to justify their existence somehow!

 

You could be right but from what I've read 221 is designed to be able to cope with a bit of flex which is what you want on a vehicle. I'd be annoyed if I found cracks and water ingress because I had used the wrong stuff, when the temperature drops and water freezes it could fail.

 

I got my info from here when I was wandering the same thing as the op:

http://www.vwt4forum.co.uk/showthread.php?t=187525

 

Everything I have used EBT on has been 100% successful. I even did some experimenting with it once to see if it was any good. I bonded 2 bricks, some tiles bits of wood etc together in the morning, by evening they was truly stuck together. One did let me down and was unsure whether to inform everbuild about the failure I had, the 2 pieces of bacon I bonded quite easily came apart I:

 

I expect they'll all do the job, one guy in the other thread said they bond bloody great trailers together with it so whatever we use in the range is probably overkill for a relatively lightweight spoiler or solar panel.

 

Sorry to be a bit of a bore about this but what do you all reckon - one tube be enough to fit the rear spoiler?