Amperage settings for aluminum

Hi peeps I’m learning to weld aluminum etc so to take of a project I have an intake manifold to weld a dbw throttle body flange into the flange measure 10mm now I saw on the chart 40amps per mm so what would be a good starting amperage to start at? Also because that cast aluminum intake is much thicker it would make sense to use a torch and heat it up to get that pool form quicker ?

Ideally you'd pre heat the inlet with a blow torch or heat gun (if you don't have a torch), then turn your tig to at least 200 amps on AC (go up to 250 if your machine allows) ideally using a 3.2mm tungsten and 15LPM gas, go full power on the pedal and tail it off once you have a good weld pool.

My machine maxes out at 200amps I’ll get some similar material to practice and dial in in firstly get familiar. Thanks for the feedback

My machine maxes out at 200amps I’ll get some similar material to practice and dial in in firstly get familiar. Thanks for the feedback

Interms if the ac frequent and balance where should I start worry more about penetration? I’ve had the manifold blasted before would obviously prep it with scuff pad etc before welding into it at least.

The best thing I ever learned for welding aluminum, is closely watching the puddle form after the oxide layer melts away. You will see the material itself start to key hole, that's when the dabbing begins.