Welding Tips and Tricks

thanks for your kind words,

i'm making header for subaru and up pipe and our header is little fragile i think. thick or thin, a lot brand subaru headers are still cracking. i just tried to minimize the risk, some other brands are using sch10 pipe too

i think you need to improve the purge side of things. its not that hard to get it completely silver on the inside.
also it looks like your pushing in filler. i would be inclined to do a root pass without filler, especially if you have no gap. then do a 2nd pass with filler. try not to push filler in.
try to keep it smooth on the inside and clean, which will help reduce cracking.