In a gas cut plate, the cut is high quality although there is some surface roughness caused by vertical drag lines. This is due to

less preheating flame

impure cutting oxygen

too slow cutting speed

smaller size cutting nozzle

thickness of metal to be cut

purity of oxygen

duration of cut

type of cutting blowpipe

Input amperage

Output amperage

Open circuit voltage

Closed circuit voltage

Salt Water

Soap Water

Hard Water

Fresh Water

Per-heat the solder

Clean the bit thoroughly

Change the soldering bit shape

Rub the bit over solder for longer period