I find "mending plates" like these from Screwfix:-
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often useful, also the corner versions of the same. However I can't find any supplier who has them in anything other than plain or BZP steel neither of which is particularly good for use outdoors.
Does anyone know where I might find anything similar in stainless steel or even aluminium or brass or galvanized.
Yes, I know I could make them myself from the piles of odd bits of stainless and ali I have lying around but off the shelf plates with ready countersunk holes are very convenient.