That's a very nice looking weld in one of the hardest spots. I have a bit of work before I reach your level but I'm still improving and I'm really pleased with how the frame I'm working on has turned out so far. I don't know if I'm really running exactly 20CFH because I use the regulator that comes on the Albee gas cylinders which is fairly approximate. Obviously any fireworks are considered harmful.

Getting a really nice consistent looking weld like that starts with good fit-up.