[fciron]

In my relatively recent experience you don't see a nice shiny puddle the way you do with steel. So, don't worry about that.

The expensive blue filters do make it easier to see what's going on. I thought I was seeing just fine through my green shade five until I tried one of the aluminum welding filters and it's a huge difference. You'll see the puddle then.

I agree thevlack of penetration sounds like not enough heat I tilt the torch more when welding aluminum than for steel, because that's what I was taught and it seems to work. I know that the higher conductivity of aluminum means it often needs more heat than the low temperatures involved suggest. I think aiming the flame more in the direction of travel spreads the heat over a larger area, countering the conductive loss without burning through right under the torch. (Hopefully. ;-) )