I looked at the miller site and saw those remotes. I don't have enough experience to say anything about them, sorry. Here is the link if anyone else can advise you:
http://www.millerwelds.com/products/...mote_controls/
The welders we're using have an arc start switch, but Im not familiar with your machine so I don't know if it has one. Probably not, or you would have figured it out by now!

Switch in one position - Standard operation so the arc and wire feed starts when you press the
trigger in and hold it. Stops when you release the trigger.
Flip the switch to the other position - You
press the trigger in and release it to start the arc and wire feed. The feed and arc keeps going until you press the trigger again.
The set up of your rotating table is a different matter altogether, and I don't have a clue about how you'd go about that. But as you see in the post above there are plenty of people on this site who have experience with that type of thing, and I'd wager more than one who've done it b4.
Is this your machine?
http://www.millerwelds.com/products/...llermatic_251/
If so at the bottom it says:
For aluminum welding, add the optional Push-Pull Module for aluminum wire feed capability. Push-Pull guns can be directly connected to the Millermatic 251 with this additional push-pull module.
Plus it lists suitable spool guns.
Here is a series of video instructions, including one for aluminiim welding:
http://www.millerwelds.com/education...llermatic.html Edit: I've looked at your machines instructions and the videos. It doesn't have a built in arc start adjustment that I can see.
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