[trg-42]

Hi Larry, which Lincoln mig do you have...the 230volt family or 115 volt family ?

Do you have the aluminum feeding kit ( polish U groove, teflon liner, etc )

Two reasons why you are not able to achieve proper arc length

1. ensure you are on DC+ ( gun reciever to the +ve terminal )
2. ensure you are not having feeding issue ( lack of WFS will create situation you describe where arc length is excessive
Test this by letting wire feed into a gloved hand...does drive rolls slip
3. ensure your spindle brake tensions is almost backed off all the way

What alloy electrode are you using...two common choices are ER4043 and ER5356 . ER5356 will feed much better....less birds nesting but ER4043 will have more penetration for give wire feed speed

You want to use ER4043 for these small MIGs

Ditch the .030 and go with .035 . Trust me on this one

Key to GMAW of aluminum

Bring WFS up high enough to ensure you can achieve good wetting. Depending on your Lincoln model you will be at least 7 to 9 on WFS
Adjust the voltage to achieve the desired arc length

Your speed and technique sounds right ( high travel speed , slight ( up to 15deg ) push angle . less than 1/2" electrical stick out