Leaning on the manifold is not likely to cause problems, vibrations and bumps have the ability to work at the aluminium over time, this is more likely to occur at a weld due to the altering of the material's grain structure. I would use 3mm thick as a minimum - as for overkill, insert the tubes and brace it as well.
When welding alloy - I like to use no less that 5000 series or 6000 series (the extruded tube will be in this range anyway, I also use extruded flat bar for the flange plate), the temper will not matter as much because it will anneal at the weld anyway (alloys in this range are generally T5 or T6).
Sun, 13 June 2004 10:53
