im still new to tig welding so im not sure if i prep my work right. i sand the area down with steel wool, then i wipe it down with acetone using a paper towel. i also wiped the tungsten with it also.

this was my first bead of the night. beveled edges, no back purging:
outside looks clean with no trash.

inside


after this pass i setup to back purge. before i weld i wiped the area down again with acetone. this time while i was welding the arc would wonder and it seem like every few seconds somthing was burning. heres the outcome:

outside-not smooth and trash everywhere.

inside- the only good thing that cmae out of this


im confused...i did everything the same...and all night i would end up with beads like this, i couldnt duplicate the first pass all night.

how do you guys prep your work? what am i doing wrong here?


anyways heres a comparison of my non-purge to purge...backpurge is the way to go

 

did you use a separate tank and regulator for your purge or the same tank with a Y fitting? are you sure you had good gas coverage from the outside?

 

im using a y splitter.

and im sure i had good gas coverage. i was using a large gas lense with a #10 cup.

 

i took welding class when i was in high school..(made side mount license plate with stainless steel, when he is not watching.lol)

i think u have to use low volt(amp)..cause it will melt right up..am i right? lol

 

Well most of our stainless is pretty damn clean so a light wipe down with acetone is all it really need but the process usually goes

But stainless, deburr stainless, wipe with acetone, wipe again with dry rag, and then tack, then weld away

 

I have no experience with this, but is it possible the argon is blowing out of the tube and that's what's making the weld poor?

This might seem like a stretch, but it almost seems like you would want a lower pressure of argon in the tube and higher pressure at the torch. That way, the argon would be flowing from the torch to the piece. With the tube pressure higher then or even equal to the torch pressure I could see the possibility of small fluid currents tumbling around and possibly bringing in contaminates from the surrounding air?

 

i guess it doesnt have to do with the way i prepped the metal.


99_gs-t made a good point. would high pressure inside the tube cause this? i dont think i made a big enough hole for the argon to exit.

or i must have my whole purge setup wrong,causing my purge line to get all the pressure.

anyone care to share on how they have theres setup?

 

I'm not a pro, but the deposits on the back make me think that you should lower your amperage (too much heat...)

 

the dark "sugar" on the inside is from poor purge. You don't want to have pressure inside the pipe, only flow.

You're welding a bit hot. The bead is way too wide. In doing this, you're only washing the bevel sides down into the middle....giving yourself more depth of material that you have to burn through to get penetration.


I forgot to add something. DO NOT USE STEEL WOOL OR A CARBON STEEL BRUSH ON STAINLESS.....unless you don't mind it rusting.

Acetone is fine for cleaning. Typically, I don't even bother to clean it unless it's oily or greasy.


Modified by Engloid at 3:32 PM 4/1/2005

 

just looks like too much heat. the second one could be from contamination but looks like maybe your tungston.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Engloid &raquo;</TD></TR><TR><TD CLASS="quote">I forgot to add something. DO NOT USE STEEL WOOL OR A CARBON STEEL BRUSH ON STAINLESS.....unless you don't mind it rusting.</TD></TR></TABLE>

I used brake cleaner and a stainless wire wheel on a dremel.. ???

 

I've never used brake cleaner prior to welding. People put way too much emphasis on cleaning stainless. As long as there's no grease, paint or large contaminants on it, you will be able to weld it just fine.

A stainless wire wheel will be fine, but do'nt overdo it. Wire wheels are usually 304 stainless at best. Sometimes, you can brush so hard with them that it can embed small particles of the brush in your metal. If you think that sounds far-fetched, I can tell you that some places I have worked would not allow usage of sandpaper, grinding disks, or flaperwheels....due to embedding particles in the metal.


My advice: wipe it with acetone and weld it.

oh, and plain rubbing alcohol works better than acetone in many situations...it just dries a little slower than acetone. Acetone actually leaves a very minimal amount of residue, but nothing that will create a problem. Alcohol is cheaper though.

 

 

yeah i often find fucktards using my stainless brush for mild steel.

asshats.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by shortyz &raquo;</TD></TR><TR><TD CLASS="quote">yeah i often find fucktards using my stainless brush for mild steel.

asshats. </TD></TR></TABLE>

I love when they do that...cause then THEY have to get me a NEW stainless brush!!! haha!!

 

I've used Brake Parts Cleaner for cleaning. It's great for really dirty parts, eats grease like nothing else, but yes, it leaves a residue. One that becomes very evident once you get it hot, smells like green apples, and will rear back and punch you every now and then.

I don't suggest it.