Gareth,

I mostly used non-anodised aluminium in my glue jobs.

The alu-oxide surface layer does interfere badly in other situations like welding so maybe it does so too with respect to glueing.

Also preparation would probably scaring the glued area with small surface cuts. It needs to be as rough as possible. I think in the document they refer to sandblasting of the area that is to be glued. This does of course two things. It removes the alu-oxide surface layer and (can) make the area rought.

Also Gareth can you describe some of the joints where the glue failed. Can you have been suffering from peel-off failure ? Were you lift one tip of the jointed material breaking the bound and progress further each time breaking only a small portion of the bound instead of the whole bound in one go.

I have thought about this peel-off problem and I think that blind riveting the corners of the plate should take care of that to a large extend.

This is all very interesting and I would love to hear more about your experience.

With regard to anodising. I hardly have any anodized aluminium on my boat anymore. Only my mainbeam and mast are anodised. All the other stuff like rearbeam, boom, spi pole , mast rotation arm are non-anodised tubes. They hold up just fine. They turn a little dark overtime but that is it.

I won't try to hard to get the F12 components to be anodised. If I build one then I won't anodise the alu parts.

Wouter