TIG weld feedback, please

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Hey guys-Finally got a chance to spend a bit more time with the torch. Made sure I had the correct filler rods in hand this time. I still am getting a bit of porosity now and then, but a lot less than the first time I ran the machine. Everything is DC TIG on 1/8" mild steel plate, cleaned with rubbing alcohol & a flap wheel. #8 gas lens with the 3/32" tung @ 20CFH. #6 gas lens with the 1/16" tung @ 16-17 CFH.First I ran some more stringers, then a bead or two using 1/16" filler wire:I defiinitely liked the 1/16" tungsten better for the ~90 amp output I was using.I tried a few lap joints with the 3/32" tung, but didn't get the best results. I'm not sure why. Perhaps because I wasn't feeding the 1/16" filler fast enough:One adjustment I started playing with was "hot start". As I understand it, this ramps up current at the start of the weld to form the pool?  It was set at 30AMPs on my machine. I have now adjusted it down to 20 amps and feel the arc is more controllable at the start. Can anyone offer me some guidance on how to set this parameter and when/why I would want to change it?All the beads above were run with the "hot start" set to 30.So, what's the verdict? Anything I'm doing wrong that's immediately obvious? Please don't hold back, I do want get better!Last edited by turboguy; 09-01-2008 at 03:16 AM.
Reply:Next, I jumped in with both feet. I figured the pile of 4"x4" pieces I had cut to practice on needed to be fabricated into something. So I made a big cube!I tried my best to do all the welds autogeneous, but had to use filler in a few areas where the gaps were larger, or when I "re-welded" an area with excess porosity....the other side:...and a close up of my best (and last) weld of the evening (with my first and worst welds peaking around the corner):All in all I'm pretty pleased with myself. Every weld I did was better than the last. I did find welding "over" my tacks welds was a 'learned ' technique. Before I would get porosity starting when I welded over a tack.By the end I was using a 1/4"-5/16" stickout all the time, compared to the 1/16" I had started with (and a very small tungsten-to-workpiece distance) in the first stringers.One thing I did notice was that my weld beads weren't super shiny. Anything I should do to change this?Last edited by turboguy; 09-01-2008 at 03:34 AM.
Reply:Just keep at it.  At the rate you are improving things will continue to get better. Post more more pics and we will help.For shiny beads, hit em with a wire wheel.David Real world weldin.  When I grow up I want to be a tig weldor.
Reply:i was taught  autogenous in ms is a no no. i guess this cube will not be used in a high pressure steam system?
Reply:Originally Posted by turboguy or when I "re-welded" an area with excess porosity.
Reply:Drill a slot for coins and give it to someone. Don't cut a hole to empty it thou.
Reply:Originally Posted by Fred Paul JonesDrill a slot for coins and give it to someone. Don't cut a hole to empty it thou.
Reply:Originally Posted by weldbeadi was taught  autogenous in ms is a no no. i guess this cube will not be used in a high pressure steam system?
Reply:Looks better than mine, at least you got a functional box....Airco 300 squarewaveMig welding center...Powcon sm300/LN 25Powcon sm200/PD lHypertherm PM 1100Miller AEAD 200LE W/LN25 FCand now another sm200 pd l combo.
Reply:Originally Posted by sunlineLooks better than mine, at least you got a functional box....
Reply:Poorly phrased; though it is a good line for the gf....Airco 300 squarewaveMig welding center...Powcon sm300/LN 25Powcon sm200/PD lHypertherm PM 1100Miller AEAD 200LE W/LN25 FCand now another sm200 pd l combo.
Reply:I made one of those boxes when I was in High School.  Only differences were:1.  Used Oxy/Acet #2 tip to weld it,2.  Filled it with water as that was the project.  Only had one spot where the steam was coming out, had to work quick to seal it.Don't it have any, unless my parents have it.  Prolly got tossed a long time ago though.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Since boxes are easily converted to piggy banks, here is a story.... Made all the rellies kids banks out of wood 6x6x6 or so. No holes cept where the money went in. My daughter had her's half full of the coppers and dropped it on her big toe. Split the nail and got infected and cost a bunch of time to heal. So the moral of the story?... Keep your banks small.
Reply:Turboguy:I don't know how to get shiny welds on MS. Propulsion and ZTFab are magic (and others). I've been in TIG class for a month, and the only way they shine is when I guench a weld. And then it's only where something 'chipped' off the surface, it's shinny underneath. A quick hit with a wire brush and it's good. Yes, I belt sand the mill scale off before every weld. (and any time I try to shortcut this, I get porosity)Since your autogenous welds on the cube look VERY good; try some lap joints without filler, just melt the edge down to the bottom plate. It seems every time you add filler, things turn to cwap. I still suspect your filler. ERxx, as I'm sure you know by now. Get out the magnifying glass and find the stamp.Another idea, start with a brand new tungsten. Sharpen it, strike an arc. Memorize the color and shape of the arc with an uncontaminated tungsten. If that changes, stop and regrind.As I said in your other thread, turn off the hot start. That's why they invented the pedal. Learn the basics first. IMHOGood luck with your welding.Craig9-11-2001......We Will Never ForgetRetired desk jockey. Hobby weldor with a little training. Craftsman O/A---Flat, Vert, Ovhd, Horz. Miller Syncrowave 250
Reply:Thanks for the positive feedback, Kevin The 1/16" filler I received appears to have had the ends chopped off where the stamp would be. The 3/32" filler I got are about 4" longer. I will try usng the 3/32" filler next time I'm in the garage since I know what it is for sure.I'll also play with some autogeneous lap welds and see what comes out of it.