Greenhouse Corner Bracket?

I'd buy a length of aluminium angle of a suitable width and cut and drill it to suit - it's pretty soft stuff so easy to cut/drill.

(Steel or galvanised brackets would be easier to find but might react with the aluminium it's bolted to.)


Edit: link to something which looks about right (I'm assuming the dimensions aren't that critical for a GH.)

http://www.wickes.co.uk/Wickes-23-5mm-x-23-5-Multi-Purpose-Aluminium-Angle-1000mm/p/188106

Hope you can rely on Wickes to have it in stock! 

(They'll no doubt be able to get it in for you if they haven't.)

I'd go round the old metal reclamation business before Wickes.   It's where I'm heading first thing Tuesday morn for some thin wall, small diam tubing.    Just lurve reclamation yards.

Cheers,  Tony.