Should You Weld Body Panels With Flux Cored Welding?
Most people will not recommend welding body panels with flux core welding. This is due to the thinness of body panels, which can range into some pretty thin sheet metals depending on the car you are working on. Typically FCAW is only recommended over the thickness of 14 gauge for adequate results whereas body panels range between 20 and 18 gauge. (0.8 – 1mm thick)
The heat generated during FCAW welding can be very intense which is not recommended for thinner metals. The excessive heat can easily blow holes through sheet metal or lead to warping. There is also more spatter and slag formation using FCAW which can cover small holes in the welded metal creating further issues. The whole process of cleaning and fixing the entire thing can take up a lot of time.
If you are not an expert in FCAW welding then I wouldn’t recommend that you fix your body panels using FCAW.
Begin with the right wire selection, you should use e71t-gs with a 0.30” diameter and try to run the settings as low as you can. Some other tips include using a series of tack welds, backing bars, and doing lap joints rather than butt joints. That’s to decrease the chances of blowing holes into your workpiece.