I would suggest that the thickening wire on the interior should be soldered in place before soldering the hinge/joint tubes in place. And using a pair of steel dividers for marking would make it easier to obtain an even width on the interior wires if they are made from sheet and also useful when positioning the joint tubes evenly. t If you don't have any dividers, I use Moore & Wright ones and there are lots available cheaply on eBay; http://www.ebay.co.uk/bhp/moore-wright-dividers
James
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