Welding 1/8" (3mm) Steel

I'm teaching myself how to weld and I'm wondering about penetration on 1/8" steel. I went through the tutorial and am trying to get the penetration to look like it does in the tutorial even though those welds are done with much thinner steel. Is the backside of a weld on 1/8" steel going to look different than the backside of a weld done on .047" (1.2mm) steel?

Thanks,
Ed

Will take about 160 amps to get full penetration and the well will be tall.

You can do it easily with a 1/16" gap with a lower current