i use 63/37 and 60/40 rosin core. sometimes i use added flux past but honestly i prefer the look of the joint without it?

I think im just not getting good heat transfer with the way the tekin escs are with those slots and i have my wires clamped fin to fit in those slots. but its just nt flowing together nicely.

do you think if i separate the joints i can reuse the same tinned solder on the posts and lead? or should i try to remove and reapply? most of the solder seem it hasnt heated up much as its kinda clump

can anyone answer my initial questions?