Ok iv given up ark welder,got a gasles mig welder, don’t laugh , so I’m having trouble laying down a decent weld , every weld looks as flat as a pan cake. No bead at all . Really p—sed of , it’s a mess, holes splatter crap
The electrical symbol for what's inside the box shows a transformer ( two overlapping circles ) only, so there's no need to discuss swapping torch polarity to negative for use with gasless flux-core wire - the output of this "MIG welder" is AC.
It probably does not have an inductor in the output circuit either, so with a 40 Amp minimum it will be a hot, smoky, spattery, and very bright arc. The lowest setting ( "1" and "MIN" ) is probably going to be hard work even on 1.5mm sheet.
Good luck with the settings on that welder..hate to burst the bubble but machines of that nature can put a man off welding for life. I was where you are 30 years ago with a similar type of machine as a newbie and made no progress learning at all..nowt!! Had a go of my mates semi-pro machine with welding gas etc and was laying down fantastic welds within an hour my welder went to the scrap man and i bought a decent machine mart welder back then and never looked back, just a thought
I've used 0.6mm Lidl wire & it works just fine.
The holes you've blown thru seems like it's 1mm steel or thinner?
The example guide below expects gasless will go down to 1mm but only with thinner wire and more adjustment available than your mig can do.
Your wirespeed adjuster does not show metres per minute, so some experimenting is needed.
You could measure yours on each setting and map it out for comparison to the guide...
If you're on 0.9mm wire your min volts of 16.1v will struggle below 3mm steel, so try the tacking approach as said above.
Or try Higher volts and wirespeed, and move faster?
Your 40A to 100A (16.1v to 19v) range with 0.9mm fluxcore seems to have a steel range of to 2mm to 5mm (ish).
Keep trying. Trying the 0.6mm wire might be worth a go.
But you might need a better machine for thinner steel....