Problems with a Precision 225 Tig welder

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My problem is not enough penetration when I am tig welding 3/16 mild steel. (butt weld)  I have tried a 1/16 gap.  1/8 works fine with no gap on a butt weld.I used a clamp-on amp meter to check the current flow while I was welding.    It measured what was shown on the digital readout. I have tried short and long tungsten tapers. I am using 1.5 %  Lan tungsten.   Anybody got any ideas?How and where can I measure the output voltages?Thanks,Jack
Reply:The arc voltage is a function of amperage, arc length, and gas composition.  There is really no good reason to measure it.  You can simply connect a voltmeter across the welding power supply connectors.   Voltage measurement is used in some automated welding systems where an automatic voltage control (AVC) would maintain a constant arc gap, or if you wanted to keep an eye on degrading electrical connections by watching for a voltage increase.As for your penetration, of course increase amperage and maintain a consistent and absolute minimum arc gap (without dipping the tungsten). I would use a 1/8" electrode with a 90 degree end prep.  #/16" probably needs a bevel and a gap, and two passes to weld it full penetration from one side.90 degree angle?  That should raise some comments.http://weldingweb.com/vbb/showthread.php...lectrode+angle
Reply:Don't hookup a multimeter to the welder outputs with the HF turned on. The HF will destroythe meter."You cannot invade the mainland United States. There would be a rifle behind every blade of grass." Isoroku Yamamoto, Commander-in-Chief, Imperial Japanese Navy
Reply:current is king in tig welding.  the only reason to check weld voltage is to check for bad connections or torches. The best way is with a load bank. but you can short the torch to the work for a second and turn up the output. see what the voltage is at the welder terminals.once you start an arc the voltage will change depending on the length of the arc. Because volts equals arc length. remember the HF will kill your multimeter. turn it off if you can.A better test is to measure the current in the torch will a DC clamp meter. then you don;t have to worry about the HF. If the weld can supply the current the voltage will take care of its self.