TIG help please......

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Hi all, first post but I've been a "Lurker" for a while getting some very good info. Anyway I'm on a project that calls for a flat bracket in 1/2" crs plate to be tigged to a piece of 1 1/2" round tube (1/8" wall), the plate is beveled on the joint and can be welded both sides of the joint. I'm using a 200 amp inverter tig, settings are 190 amps, 1/16 2% tungsten, 1/16 er 70s-6 filler, 18ft of pure argon and a no 6 cup. When welding from both sides I get a nice looking weld (but a bit grey)but have no way of determining strength of weld (which is what concerns me), I do have a problem sometimes with the tungsten melting (too high amps for size ?) so will try 3/16 tungsten.What are your opinions on my settings? obviously you can't see the weld (I'll try to post photo's) Gratefull for any advice.
Reply:Perhaps 3/32 tungsten would help.  Otherwise we need pics.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Oops! I meant to type "I'll try a 3/32 tungsten" not a 3/16th.
Reply:It does sound like you are running too small of a Tungsten for the amperage.  We run a 3/32" Tungsten in class welding 1/8" steel at 60-70 amps.Miller Syncrowave 200MillerMatic 180 AutoSetHobart Airforce 500iVictor O/A (80cf)
Reply:Try a 1/8 tungsten for this current.I would probably run this with three passes wither side, at about 120 to 130A with a 3/32 tungsten, to reduce the total heat input.
Reply:I would be very careful running that 200 amp inverter at 190 amps as it would likely be very easy to exceed the duty cycle. Mine is a 300 amp Miller and will only run 160 amps at 100% duty cycle. Even if it has a thermal overload it isn't good for them to run them until they hit it.The difference between art and craft is the quality of the workmanship. I am an artist.