You didn't give enough specifics. What are you getting and what do you want.
It may only be 1/16" in cross section but what is the area?
Aluminum is a notorius heat sink and sometimes rather than flow it will just continue to soak up the heat from your torch untill the entire work reaches a preheated temp if the work is not so large it can give up the heat faster than you can apply it.
This means increasing you heat input making for a larger puddle. My thoughts would be to try preheating your work and don't get in a rush.
By that I mean don't crank the amps up so much you melt more area than you want to.
Do you have a gap at the butt?
How much? plus the other questions from EVWELDER?.
Are you useing AC & High freq? Is it new material?
Is the material clean? Some Aluminum comes with a coating. Or if it used material it may be Anodized.
You should be able to put down a bead the same as you can in Steel.
Or roughly 1 1/2 x the filler.
Mike,
For 1/16th inch 6061 Aluminum groove welds here are several tips to get a thinner bead profile.
If your torch is water cooled use a 1/16th inch tungsten with a pointed tip and blunt the tip slightly. (cerium or zirconium). If air cooled put a point on your 3/32 electrode (not a long slim point, rather a more radical angle)
Mechanically remove oxide from both sides of the material out 1/2 inch away from the weld right before striking an arc. 120 grit aluminum oxide sanding discs are best, a wire brush is just ok.
Set the balence control on your synchrowave 250 to 7 or 8, (more toward max. penetration) the higher the better as long as your getting sufficient cleaning action. This and your travel speed will have the most to do with your bead profile.
To get a small profile on the thickness you suggest the fit up must be perfect. This means no gaps and no roughly sheared edges.
I'm assuming your using 4043 filler wire.
Thin aluminum is welded best hot and fast. This takes some practice but in the end has the greatest effect on bead profile.
Set your machine to 90 amps, This way you don't have to wait for heat to build up before you go. You will use almost all of your footpedal for the start and then you will need to back off as the part gets hot, as you approach the end of the weld you will be nearly off the foot pedal.
In a groove weld it is normal to have to add a dab of wire to the two pieces to get them to fuse so don't worry about that.
The 0.063 (1/16) wire your using is just fine. I sometimes like to use a heavier wire 0.090 (3/32) for your thickness, the heavier wire can have a cooling effect on the puddle and makes for even faster travel speeds, again this takes a bit of practice.
Adding wire will become rythmic, as the pool becomes concave you will dip and move forward, dip the rod a little into the puddle rather than right on the leading edge like you would do with steel.
Keep your torch angle straight up and down (90 degrees), the heat goes where you point the tungsten and will make a wide dish if pointed ahead or to the sides.
You have a great machine and thats a big part of the battle with aluminum. With a few trials you will have a bead like a row if dimes.
Finally, don't be alarmed that your weld profile is wider than that of a similar thickness of steel, with larger reinforcement (penetration) on the back side. That is also normal for aluminum. Mil Specs and Codes give a greater allowance (sometimes twice as much as steels) for bead width and reinforcement.