it is welded tube but this is only a mock up, i do intend to get CDS tube, now that you mention Ash G's issue with the stays i do recall reading that in the "Guide to building the Haynes Roadster" i will address this thank you for bringing that up.
as for the changes here, i have put these vertical ones here and i'm puting them also on the corners for extra strength.
here i have put an extra peice of 20mm box from the tube to the top of the rear suspension plate with a corner piece of 3mm plate this will be for my full roll cage / rear support stays. and will also act as a support for when i but my "boot" in made from aluminium (after IVA)
