Newby help starting a pool AC Alloy

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Hi GentsI have been oxy/mig/stick welding for years, but I recently purchased a Tig because I want to weld some aluminium. So I am a total newbie at it.It has taken me quite a lot of research and many hours practice but I am slowly getting the hang of welding alloy. Besides the following niggling problems, for the most part the welds are quite nice, or I should say definitely good enough for what I am doing.I do however have a few little annoying problems. I am welding 1.6mm square sections together for a caravan frame. I am having trouble getting a pool to start unless I melt a bit of filler rod to get it started. I can crank the amps up to about 120 or so and it starts a pool ok but its too high to continue without blowing holes. I dont have a foot pedal.I am about to do some more research on preparing my tungsten, but I also have trouble getting a stable arc at times. I have several of them presharpened and ready to go, yet some of them seem to be more stable than others, so I am convinced it is my slap happy way of sharpening them with the grinder??  I just sharpen them to a point, is that correct?Also, my tig doesnt have a manual with it. It is a Mitech or something like that, it may be Chinese? However, can someone give me a guide on what settings would be close for welding 1.6mm alloy. I am using 1.6mm tungsten tips and 1.6mm or 2.4mm filler rod. The alloy is a very standard 6xxx something grade.I am not totally sure what the upslope/downslope and pulse width are for!! Sorry for the silly questions, like I said I am totally new to welding alloy. I have simply been experimenting with the settings until it works!Welding steel with this thing on DC is simply brilliant. I wish welding alloy on AC was as easy.Once again for the most part I am happy with the welds, but any help will be very much appreciated.regardsDanny
Reply:A couple of things:  First don't use pure tungsten, use any alloyed tungsten, thoriated, ceriated, lanthanated.  Without a foot pedal you are at a disadvantage as you say.  So I would say use enough current so that you don't have to wait forever to get a melt, then weld fast enough to avoid blowing through, this may mean that you really need to hustle along.  When you start, you should get a bit of melting on both sides of the joint as you add a dab of filler to bridge the joint and form a single pool.  Keep a tight arc length to concentrate the heat transfer.
Reply:What you're trying to do, is equivalent to driving a car in heavy traffic,that has no throttle control or brakes---by turning the ignition key 'ON' or 'OFF'.........as the occasion demands.Foot or hand controls for AC TIG, especially relatively thin aluminum,are not 'unnecessary frills'.Blackbird
Reply:Originally Posted by DannyGAlso, my tig doesnt have a manual with it. It is a Mitech or something like that, it may be Chinese?
Reply:For weld parameters, as well as a wealth of other information about GTAW, you should really check out the TIG handbook produced by Miller. I'm learning TIG too, and it has been an essential read even with a machine that *does* have a solid manual of its own. http://www.millerwelds.com/resources/TIGhandbook/You probably also want to look into finding/building a foot pedal for your machine; it's really helpful. Not sure about that machine, but if it has a sequencer (settings like initial current, ramp-up, etc) you might benefit from using the "initial current" for preheat before ramping up to a reasonable weld current? Check out the TIG book though - all available for free online, and an amazing piece of literature!.p
Reply:Wow, just downloaded that info. Thanks Miller, If I read it I might be on my way.Thanks for posting.Bob.Miller Dynasty 200 DXMillermatic 211Hypertherm PM 600In Tool acquisition Mode
Reply:Thank you very much for all the replies.The button on my torch appears to slow the amps down when i let it off slightly...or maybe i am imagining things??Anyway, once again thanks, i have downloaded some manuals so ill sit down and try and work out what these dials do when i get time.