Beginner TIG welding dissimilar metal thicknesses

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Hello - I'm fairly new to TIG welding, and I've gotten slightly competent at simple joints with similar thickness materials.My first big project is a balcony railing: 16 gauge 1.25 square tubing frame with 1/2 inch solid steel bars for ballusters.  I've been making a lot of test welds and I've got the T and miter joints with the square tubing working fairly well, but the T joints between the 1/2 inch solid to the sq tube are wildly inconsistent.  Here are my settings (Miller Diversity 165)1/16 Thorium electrode, #6 cup, 11 CFM argon, 1/16 ER70S2 filler rod, 75 amps.  Parts to be joined are cleaned up with wire brush and degreaser prior to weldingI realize that the 1/2 solid is going to need more heat than the tube, so I'm angling the torch more towards the bar than the tube.  I've been trying a lot of different techniques and power settings. The problems I'm seeing are twofold:  either I don't get adequate penetration on the solid bar and have a weak joint or I add too much power and blow a hole through the tubing.  I can't seem to find a happy medium.  I know practice is the key here, and that's what I'm doing.  I've got lots of extra material and I'll keep at it until I get it right.  I'm just trying to verify I'm on the right track with the settings.I also realize that normally MIG welding would be used for this type of project.  I'm assuming it is at least possible with my setup, but borrowing/obtaining a different setup is always an option.Suggestions?Thanks,Kent
Reply:you might think about a thicker tungsten for higher ampsare you using a foot peddle if so then turn up ampsto get 1/2 puddle then wash to thinner metalidealarc 250/250 ac-dc tigidealarc 250/250 ac-dc tig #2 used for sticklincoln sp100hh125dual arbor grinder polisher30 yrs of hand tools52 pitch blocks 6p-26prake gauge -pitch gaugeG&D prop repair 918-207-6938Hulbert,okla 74441
Reply:Thanks - I am using a foot pedal and I can switch to 3/32 tungsten.  What amperage would you suggest?
Reply:will take amps to puddle 1/2 so maybe start 100-150  then throttle down for thin use some scrap to get a start setting as we all know the thinner won't need  that much heat you just need to wash it to the thinner JUST an FYI  its  CFH not CFM ((cubic feet per hour)idealarc 250/250 ac-dc tigidealarc 250/250 ac-dc tig #2 used for sticklincoln sp100hh125dual arbor grinder polisher30 yrs of hand tools52 pitch blocks 6p-26prake gauge -pitch gaugeG&D prop repair 918-207-6938Hulbert,okla 74441
Reply:Since you just practicing why you go with thicker wall tubing, like .095 ?
Reply:I would set the welder for full.  Hit the pedal on the 1/2" until you have a puddle then move towards the tubing with the filler ready.  Dip the filler as soon as the puddle is ready and move along. Cut the pedal back to keep a puddle going.  Keep the tungsten close to the 1/2" with the edge of the puddle and heat on the thinner metal.  You only need a bead as large as the thinnest metal.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Originally Posted by kbmyersSHORTENED TO SAVE SPACESuggestions?Thanks,Kent
Reply:Thanks for the tips!  I'll give those a try as soon as I get my argon tank refilled - I emptied it this morning while practicing.  Why does that always happen on Sunday when the welding supply store is closed? Thanks again,Kent
Reply:Donald - thanks for the detailed reply.  While I don't disagree with you regarding the tubing thickness, this was the material recommended to me by the local ornamental supply company that specializes in gates, fences, staircase railings and balconies.  It is also the same material that the original balcony was made from (which lasted 20 years until the mounting brackets rusted out).  I also fully plan on meeting all code requirements.Like I said, I don't disagree on the tubing thickness and I'll look for thicker material from another source, if only to make the project easier to weld.  Also, the whole project will be welded in my garage, out of the wind and away from bystanders.Thanks,KentLast edited by kbmyers; 11-13-2011 at 07:39 PM.