Contamination problem

[OldSparks]

drewworm

I don't know the workings of your syncrowave but the lift-arc on my XMT works by touching and maintaining contact momentarily before pulling away. If I get too quick, as in a scratch start, there is a tendency for the tungsten to stick. Is it possible that you have to wait longer after you step on the pedal before pulling away? As for your porosity, is it possible that when you are fighting the lift-arc that you are either twisting your torch or long arcing? Either can start the problem. Also do you know that you can't burn out porosity and that by going over a weld that may have a slight problem will only make it worse. The only way to get rid of porosity in a weld is to grind the whole area out. This can mean having to open up a hole an extra 1/8" into the base metal to make sure you got it all.

[drewworm]

I know from trying that the porosity cannot be welded over. It's frustrating. I have ground some out and welded back over.

[drewworm]

oldsparks

Forgot to mention that I will try leaving the torch on the work for a little before lifting.
Thanks

[joebass]

Although this does sound like a gas issue I have had mild steel that no matter what, I do it has porosity, if I switch to a SS filler it goes away. Try a 309 or 308 filler, see if that helps.

[burninbriar]

Although this does sound like a gas issue I have had mild steel that no matter what, I do it has porosity, if I switch to a SS filler it goes away. Try a 309 or 308 filler, see if that helps.

I have run into the same situation and used the same cure. (learned the cure from this forum)

[dirtmonster17]

i was trying to weld the same thing last night im no expert on this but i know why mine was staying contaiminated.i did not clean the metal properly try cleaning the metal with a grinder and see what happens.how much heat where you using?

[Revlimit]

I've also gone to Stainless rod in these cases and it has been a cure for problems like this. Since all we use is 316L, this has been what I have used.

[drewworm]

Contamination - SOLVED

To everyone who helped me on this issue...Thanks for your patience. I've been dying to get back at my project, but my real job keeps getting in the way of my fun. Today was the best welding day of my life. As I mentioned before, at one point I went through 2 inches of tungsten in one day and that was on about 8 lineal inches of weld bead.
I took a lot of the advice in this forum and here's what I did:

1. Increased gas flow to 17 cfm.
2. Decreased electrode stickout to just 1/8 inch.
3. Set the syncrowave on High Frequency "start" (NOT "lift-arc").

I put a new point on my tungsten and started welding. I only had to re-grind ONCE! Yet, I did five times as much welding as the other day and no contamination.
My feeling is the "lift-arc" feature on my machine was the whole problem. I swear that upon starting, the electrode was "freezing" to the work and grabbing a small piece of steel thereby contaminating my tungsten from the start. None of those problems with HF start.
Thanks everyone.