Please look at these pictures first.


This was done on a ss pipe, the weld in the bottom picture had 308ss filler, clean 3/32 tungsten, very clean work piece, no spatter at all, nice arc at 60amps ad 15+ cfm.
The problem is the weld do not come out shiny like the should. They were all covered with these black stuffs no matter what kinda of adjustments I did. I even went and put Teflon on all of the gas connection. I was told it could be contaminated or wrong gas, i went and got a new cylinder and the problem reamain! Does anybody else have any idea?

 

how thick is the material?

if it's 16 g or thinner id turn the heat way down and try a diff piece of rod

 

no filler was used on most weld, i even try to do one spot weld with all kinda of heat setting ranging from 10amp to 100amp.

 

u sure the gas was on? was there a draft where you were welding?

 

i'm sure the gas was on, i can hear the postflow and preflow, there is no draft at all.

 

Looks like it was to hot to me.

Usually when a weld is to hot you burn out all the important metals in it that create that shine like the magnesium and cromium.

 

Was the ground good?

 

the ground clam was directly on the workpiece, heat is not an issue since I even tuned it down to 10amp.

 

Does your electrode tip have some steel on it? Is it a sharp tip?

 

No, the tungsten was still shiny clean after the weld. Everything was cleaned with acetone. I know it doesn't make sense, but that how it is and it's driving me crazy. Could it be the fault of the machine?

 

are any of your collet body holes stopped up. Had the same problem with another torch. If you ever dip your tungsten into the pool the metal will run up the tungsten and settle on the collet body blocking the gas holes.

 

i had a similar issue, in the end it was bad gas.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by prostock &raquo;</TD></TR><TR><TD CLASS="quote">i had a similar issue, in the end it was bad gas.</TD></TR></TABLE>
That what I was told as well, i went to the same place and got another tank but the problem remains, could it be a bad patch?

 

is it 100% argon??or is it argon/carbon dioxide?

 

try the largest cup possible and a gas lens. then try to vary gas settings. high gas through a small cup can create too much velocity. i would try from 10 cfh to 18ish personally. how far out is your tungsten? does it have a color on it afterwards? what type of tungsten? (there is a color band on it to determine) and finally, what are the welder settings, as in AC, DCRP, DCSP, hf, balance, arc stabilizer, etc.

 

Got some great tips so far, and the problem could be any of them.

I'm thinking of these, the first things to check would be the type of gas which should be Argon.

Also, the size cup. I don't know why some people like little cups, but they suck for gas coverage, and turning up the flow doesn't help.

And the amount of tungste sticking out...shouldn't be more than about 1/4" for something like this.

all the other ideas are legit also...

can you get pics of your torch, showing the tungsten and cup?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LostCRX &raquo;</TD></TR><TR><TD CLASS="quote">the ground clam was directly on the workpiece, heat is not an issue since I even tuned it down to 10amp.</TD></TR></TABLE>

When my friend first got his thermal arc i was trying to set it up and my welds on a similar stainless pipe looked Identical. Like i said earlier the ground turned out to be the problem. I even had it grounded on the pipe itself. I spend 2 days messing with it...Then i stuck the pipe on a 1/2" steel plate and grounded off the plate and the weld was beautifull..

 

wow, i appreciate everybody help.
Everything is set according to the Miller manual. However, the cup is kinda small. I will get bigger cup and a gas lense this weekend. The gas is 100% argon, this is a new tank that i just traded in with my old tank thinking it might be contaminated. I will also check my ground, I will try all the suggested idea and take pics along for any further help. Again, thank you everybody for helping so far, this board is the only thing that is preventing me to burn up the machine with 1000 liter of gasoline.

 

while you are at it, try some other materials and take pics, with note of the machine/gas settings.

 

keep us posted

 

First off, I would like to thank everybody for helping out, i was really frustrated from everything. But i think the problem is solved. I don't know which suggestion worked b/c i tried out everything. More likely it was my ground since the ground calbe was barely hanging onto the machine, either that or the new cup with gas lense. Gas lense is so cool
Here is the new cup, it's a 7 cup with gas lense.

here is the work piece, a flat sheet of ss.

Note the shine on the spot weld, and compare the before and after pic.
Before

after

The aftermath

When I stop the arc, I hold the torch there for the postflow. I dont know why it always shinier at the end of the bead where I hold the postflow.
Gas was set between 15-18, power is at 60 amp, Red brand tungsten with cup 7 and gas lense. Nonetheless, i'm happy the problem is solved, this is where the learning really begin.


Modified by LostCRX at 12:28 AM 1/30/2005

 

im real glad for ya man, rock on. im not sure about the shine, but would like to hear opinions on that. taper off the heat at the end of the arc to avoid those craters that lead to cracks. an extra big dip of rod on the last dab can help too. also, back in your tungsten as far as is reaonable and it will contaminate/accidently dip into the puddle less. welding books recommend one tungsten diameter sticks out, which i think is a bit on the short side but.. your call.
i personally rest the cup on the piece before starting, set my torch angles up and then put the tungsten whatever distance in to give me the distance from the work i desire. it was a big improvement for me.

 

btw, i sure dont mean to beat you up because im very far from being a great welder, just trying to be. you mentioned wanting to learn more though, so ill throw this in.

it looks like the new beads were without filler, yet are ripply. when i see engloids welding, i usually see less tendancy for ripples. they seem to simply be cosmetic and are more a consequence of filler addition, since its added in dabs rather then steadily. when i stopped trying to be pretty and just focused on steady torch dragging and filler, my welds got waaaay better. they lay into the bevel flatter and have less texture to the fingertip than before. i try not to make ripples and figure its probably more of a steady penetration rather than a patchy one, which most certainly means greater base metal admixture, and thats what its all about right?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LostCRX &raquo;</TD></TR><TR><TD CLASS="quote">
When I stop the arc, I hold the torch there for the postflow. I dont know why it always shinier at the end of the bead where I hold the postflow.</TD></TR></TABLE>
You answered your own question there. The reason is that you're welding too hot or too fast...probably too hot for your travel speed (combination of both). Therefore, as you're moving along, the weld, as it leaves the argon shield is still much hotter than it should be...giving the dark color. At the end, taper off the heat a little more slowly just so you don't get a fisheye. It doesn't look like that's really a problem though at this point.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LostCRX &raquo;</TD></TR><TR><TD CLASS="quote">
Gas was set between 15-18, power is at 60 amp, Red brand tungsten with cup 7 and gas lense. Nonetheless, i'm happy the problem is solved, this is where the learning really begin.</TD></TR></TABLE>
Now that I see your amperage, I'd bet you're moving too slowly....60 amps at a snail's pace will put much more heat in the metal than 60 amps at twice the speed. Just speed up a little bit. Don't rush though. I usually run my gas at about 25 as an average, and most other guys that weld for a living do also. If it's a money issue, go ahead and leave it where you are though. As you improve, speed will increase and running 25cfh won't be nearly as costly as now, when you're still taking quite a while to make each weld.

Much improved though. Glad you got it straightened out. You may want to weld around the pipe a bit though, since that's how you'll nearly always weld any pipe.

 

Thank you MIke and engloids for taking your time to help out.
Mike, it's interesting that you brought up the subject of steadily moving the torch instead of doing patch to get the ripple effect. I use to do mig so I stil have the tendency of doing the "go-stop-go-stop" technique. Maybe we can get Engloid to chip in regarding this subject. Nonetheless,I will keep all your suggestion in mind next time I weld.

Engloid, I listened to you and busted out some scarp ss pipe i had laying around.


If it's possible, can you give me some tip regarding welding pipe? I found it really awkward having to rotate the torch, it was a bit hard for me to keep the torch perpendicular to the surface being welded, thus I ended up doing like 5 beads of a 1.5" pipe.