GPoodle

Hey guys,
Im about to make my downpipe and dumptube and I'm having a problem with a TIG machine. now normally, I use a continual-feed MIG welder, but its messed up and the wire doesnt feed smoothly or constantly (and I cant get this fixed because Im using equipment at a shop I work at during the summer, and since I havent gone to college for welding, Im not supposed to use the welding machines).
So... since the MIG's messed up, I'm forced to use our TIG welder. I cant seem to get a good steady bead at all, and I'm not sure if my technique or amps are correct. basically what Im doing is pushing the foot pedal (which causes some gas to flow), then holding the trigger and moving the gun close to the metal until the arc is formed. After this, I just stick the filler rod to the metal where the arc is jumping to and try to get a little pool and push it around.

But, as I stated above, I havent been able to get anything that looks good more than about 1/4" and its still nothing like the TIG beads we're used to seeing. I'm also getting what looks like bubbles in the molten metal.

So the question is, what might I be doing wrong? I was using the "positive electrode" mode, instead of AC or "negative electrode", is that the right one to use? I also tried 80amps, and 180amps and 180A was definitely easier to get the filler melting and to work with.


So, if anyone could shed some light on what I may be doing wrong, please chime in! I'd rather not have a bunch of shitty, frail welds and I'm trying to get info before I do this.

Thanks!
-jonah


Modified by GPoodle at 8:54 PM 1/12/2004

karmannghia

You have to find the right amp to work with...First make a pool out of the metal that you are welding and it will automatically suck in the filler, then it is downhill from there..but the key thing is clean metal, and good argon, and optimum amperage.

Sonny

You should not be using positive electrode unless you're welding something that requires very shallow penetration. Positive electrode focuses most of the heat on the tungsten and not on the work piece.

Switch to negative.

On most machines (this one is mine):


you have a "coarse" amperage adjustment (the 2nd lever over) and a "fine" adjustment. Set the coarse amperage adjustment such that there is enough amperage for what you're trying to do (say 150 amps). The fine adjustment (0-100) is a percentage of how much of the coarse power you get with the pedal all the way down.

Ie, on my machine if I set the coarse to 310 amps and then fine to 50, I will get 310 x 50% = 105 amps with the pedal all the way down.

Make sure you have a good sharp tungsten and that the gas is flowing.

If you've never used a tig welder before, practice on something besides your downpipe.

Sonny

EMI

Damn i need to get my new welders

This One

Try starting running a bead by stitch welding it,
Just continuously tack it together to create a bead.
Make one puddle and let off, move and start a new puddle, let off, move and start a new pudle

NJIN BUILDR

Migs are usually set up with Argon mix.You need straight argon for Tig(at least as a beginner).If the weld looks all porous the heat is to high,although the argon mix will give you those results to.
Glenn

ffgeon

i think sonny meant to say 310x.5=155 not 105. but maybe his machine is crazy (or maybe he is) and it comes out to 105 at "WOT".

paulzy

iTrader: (1)

Try practicing on scap metal first. You want your tungsten to have a fine pencil point to it with teh grain running up and down, not sideways. IF you're grinder wheel has been used on other things, clean the tungsten after sharpening. Clean teh metal really good too.

You know how to work teh amperage, so jsut practice on similar scrap metal to what you're welding and it will come to you.

I suggest running some beads without filler material first, just so you get the Idea.

Oh yeah, what filler material are you using?

Sonny

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ffgeon &raquo;</TD></TR><TR><TD CLASS="quote">i think sonny meant to say 310x.5=155 not 105. but maybe his machine is crazy (or maybe he is) and it comes out to 105 at "WOT". </TD></TR></TABLE>

Damn, math 0wnz me.

Sonny

GPoodle

Hey thanks everyone this post was really helpful!!
I'll be back at the shop tonight swapping an axle out so I'll try welding with the changes you guys mentioned.

Thank ya!