Welding Advice required

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HiI am preparing to build a bob skeleton racing chassis, I will be buying a sheet of S515, carbon steelwhich is the mating sheet material for BS4T45-BS4T100 carbon steel seamless tube.This sheet will be laser cut for parts then fabricated.What is the best method of welding this material, the welding joints must be robust and able to handle stress. This video link provides a idea of conditions the weld joints must cope with....wait for vid to buffer, hit play top left hand corner of linkhttp://fibt.pixabit.de/index.php?id=97&track_id=7&L=0Thanks for your helpMongoose
Reply:Mig and Tig will both work fine.  My concern would be your welding skills.  I would not want to risk my life on a project that is my first time welding.
Reply:Originally Posted by MONGOOSE505HiI am preparing to build a bob skeleton racing chassis, I will be buying a sheet of S515, carbon steelwhich is the mating sheet material for BS4T45-BS4T100 carbon steel seamless tube.This sheet will be laser cut for parts then fabricated.What is the best method of welding this material, the welding joints must be robust and able to handle stress. Thanks for your helpMongoose
Reply:Hi The welding will be done by a professional, I was advised that Tig Welding and Brazing are the preferred methods using a CIF Bronze A32 Rod. MIG Welding can be used, but is not a preferred method.What are the key differences between these choices and why is mig not preferedThanks
Reply:Originally Posted by MONGOOSE505This video link provides a idea of conditions the weld joints must cope with....wait for vid to buffer, hit play top left hand corner of linkhttp://fibt.pixabit.de/index.php?id=97&track_id=7&L=0
Reply:A32 is a carbon steel alloy, not a brazing alloy. Probably better known as er80s-b2 on this forum. As brazing was mentioned i assume that the chassis are used 'as welded'. It's common for a lower strength er70 (A15 / A18) type filler to be used in similar fields (automotive/aircraft/bicycle)- the weld deposit is more ductile, the size of the weld deposit compensating for it's lower strength.  MIG vs TIG... TIG is a low deposition process (read, relatively slow) but offers fantastic control and precision. MIG is high deposition, less precise than TIG and prone to 'cold starts'. TIG is just more suited to the type of welds and material thickness that will be required for this
Reply:I would consider waterjet cutting on parts to be welded, to eliminate any possibility of there being a heat affected zone around the edge of all the pieces.