First time welding 2" 304 Stainless Tubing - butt weld
1/16" 2% T-Tungsten 35 Amp - Argon
The bead looks pretty good (newbie) but is it normal for the inside of the tubing along the weld to be so ugly ?? What am I missing?

Is is possible to tig weld brass to mild steel and if so what should the filler material be?