I have a mig welder that gets the job done. It gets a little hot and I've certainly left some black spots in the past, but it's functional even if ugly.
JB weld is not technically FDA approved but once it is cured and hardened, it's definitely food safe and non toxic and shouldn't leave any flavors at all. It's rated for super high heats and extremely difficult to remove. Even still, whenever I use it on an application, I still only use it on exteriors just to be safe. I've never had any issues before when using it on some of my brew gear.
Again, the professional ones are much nicer, prettier, and overall no doubt are they better. But most times I go for functional, useful, and I love to build and design stuff. If it saves me $30-40+ at the same time, even better.