[pro mod steve]

Long story short 5/16 flat plate t-weld and about 5 seconds after I lit up it spit a couple of small chunks out of the joint and welded my tungsten lense and cup together. Material appeared to be clean enough wiped with acetone clean tungsten and all that. What the hell it was no big deal just chunked the plates got more from another source and all was fine. Was there contamination possible in the poors of the material? It wasn't nasty scrap either.

[pro mod steve]

17 hits and no answer or guess?

[ogorir]

not offhand, no. I've had that happen with aluminum, and I've had that happen bridging the filler from the tungsten to the workpiece on off-angle stuff, but I've never had the puddle jump at the tungsten of its own volition while welding steel. any chance you bridged the filler across the arc gap?

[jakeru]

Sorry I haven't had this happen to me before either. But can you clarify which torch parts were welded together? "Tungsten, gas lens collet, and cup? All welded together?

That's bizarre, it takes a *lot* of heat to get a cup to melt you know, if that's what happened. I think a stray arc could do it though. Makes me think maybe the arc or ground was traveling through it somehow... (maybe some dirt on the surface conducting electricity?)

I've had an occasion where the arc went places unexpected because the ground wasn't hooked up to the work properly. I remember a spot in the center of the palm of my welding glove getting really hot. Arc somehow went into my glove and out of it in another spot, traveling through my torch on/off switch's metal pivot (and from there, who knows...) finding its path to ground. I stopped welding so fast on that, let me tell you it freaked me out. Sure enough, forgot to hook up the ground clamp! I think I will always, always wear gloves on both hands when TIG welding anything, let me tell you.

I've had the arc melt one of the edges of a gas lens collet before, but its because I didn't have a cup on there at all. (I was experimenting how to reach a really tight access joint... actually worked for a few seconds, until I moved it wrong.)

I've had steel boil and "spit" at me when welding, usually only it when it is dirty though (carboned up, rusty, etc.) Perhaps there was some ingredient inside the steel that boils before the rest of the steel melted. That would build up a pocket of pressure. Once the surrounding metal melts - "pop" - out spits some molten metal.

[pro mod steve]

It just spit a small piece of molten like metal from the joining edge of the t joint and went in the cup and basically fused i guess is the word my tungsten gas lense and cup to the point where they were all stuck together and I could not independently disassemble the torch parts.

[Polaris_Dave]

Where was your ground connected? To the vertical T?

[pro mod steve]

work was on steel table ground was to clean steel part of table. Never had a problem this way before

[Gary]

The only time I had that problem with bridging like that was trying to weld caster wheels to a frame and they where a brite steel that must have had a lot of zinc or galvanizing it the metal It would spit and spark like I was stick welding it so I opted to bolt them on.
Gary

[TT350]

I’ve had this happen before.
I come to the conclusion that the steel
has pockets of air trapped and when you
come to them the heat builds pressure and
when the puddle reaches the pocket it explodes
spitting steel in your torch.

You can think china for that.

I have uncovered threads before when milling
steel.

A part was on my desk for a week or so and
I was looking at it passing the time and noticed
some little lines.

I took it to buddy of mine “another machinist”
and he told me that he runs across it from time to time.

95% of my work is on aluminum, when I get
a small job working with steel I buy it for his boss.

He is a tite wode so more that likely the steel he stocks
comes across the pond.

[pro mod steve]

thanks

[torn7th]

Ive hasd this happen also on mild steel (carbon). It has alot to with little air pockets in the molding process. Cheap forging basically. I had a air pocket and a piece of metal popped out and of all the places to go it decided to travel down my back. I dont think ive ever got a shirt off that fast in my life lol

[sschefer]

It's happened to me but it wasn't bad steel it was drops of sweat comming out of the band in my helmet. It happened a couple of times before I figured it out. I got one of those nice sheepskin liners and that fixed it.

Really, this is true.. When I'd do my last fitup check with the the helmet on and up the sweat from my forehead dripped into the joint and I didn't see it. I guess when the heat hit it, the hydrogen and oxygen parted ways and it popped and blew a hole in my weld. It happend a couple of times and was really making me mad and then I saw it.

Now that's not to say this is your problem but it could be moisture or oil comming to the surface so try preheating it with a map gas torch. Can't hurt and might just solve the problem.