A few month's ago we had 2 separate people come in with no welding experience at all wanting to build their own airplanes. One guy wanted to use TIG and the other guy said O/A can be used as long as it's inspected. Building an aircraft you want to fly and even a 2 seater is not a good idea for your first welding project. Probably not a good idea for 100th welding project. LoL
On the other end of the scale, a woman I worked with(who was clueless but tried to fake it) told me I shouldn't recommend what welding rods a customer should use on a boiler. Actually, it wasn't a boiler but a wood heater he wanted to line with a stainless steel bottom. I told him 309 is used to join stainless to carbon steel. I told the woman I wouldn't recommend rods for a vessel or something critical cause that's up to the engineer but considering it's a welding supply, I figure that's why people go there for welding advice.