I work for an Ag Equipment Manufacturer and have an application whereby the design engineer would like to fuse/join (2) roll-formed carbon steel component parts whose material thickness each are 3/16 inch (when joined the total laminated thickness would equal 3/8 inch). From what research I have conducted I have not seen anything made out of a low carbon steel that has been spot welded beyond 1/4 in. in total thickness (ie. 2 substrates whose accumulated thickness is no greater than 0.25 inches).
Note: these roll formed pieces have a length of over 35 ft.

Am I correct to state that at present spot welding (2) pcs of low carbon steel together that each have a material thickness of 3/16 in is not a viable option and would therefore need to look at other weld processes?

MM