dark welds

[corn]

When welding 4130 thin wall .058 to .085 the welds look good but it has a dark color to it. I even removed the coating on the tube and cleaned it with acetone before welding.

[fuelcarbuilder]

corn, from the looks of the pic, it is a shielding gas problem. Could be anything from too little/too much argon flow, to wrong cup size, to bad gas lens (if you use one, look for weld spatter on the screen)...even welding too slow/hot will cause this look from heat build up. Also if there is a leak in your torch head or supplying argon lines, you could be sucking Oxygen into your flow path. Common problem with many causes. Check everything out...or it just could be you're holding your tongue on the wrong side of your mouth Merry Christmas, bOb

[calweld]

or it just could be you're holding your tongue on the wrong side of your mouth Merry Christmas, bOb

Hahaha

????? I thought it had more to do with the stage of the moon????? Or sunspots??

Don't start getting everybody confused, now

[M1.30-'06]

Looks overheated to me. Is that a single pass or did you go over it again for some reason? It is hard to tell from the picture.

Is this a problem that has just started happening? More details please

[corn]

What would be the wright cup size for welding with 1/16 electrode? If it is due to over heated condition would the weld still be strong but just dark in color?

[Engloid]

Looks a bit hot to me. It should hold up fine though.

Although others will disagree with me, I will NEVER reccomend using 1/16" tungsten, unless you're welding under a microscope or something like that.

[lwhiway]

I will NEVER reccomend using 1/16" tungsten, unless you're welding under a microscope or something like that.

I've never used that small of size either for any application, of course I don't own a microscope either. lol

LW

[corn]

Thanks for the help. What is a common practice for choosing electrode size? I am fairley new at this and any help would be appreciated.

[FABMAN]

hey everyone, is it just me, or should the pipe fit-up have more of a fish mouth to it ??

[Pile Buck]

hey everyone, is it just me, or should the pipe fit-up have more of a fish mouth to it ??

Fabman whenever I work on my own, not going by a set of drawings, say like on hand rail. I would only shoot for a heavy 1/3 the outside diameter of the pipe. OSHA only requires handrail to be able to withstand a 200-pound impact if memory serves. But whenever doing anything really structural I would shoot for 1/2 the outside diameter of the pipe. But here is how the book says to do it.

[FABMAN]

Fabman whenever I work on my own, not going by a set of drawings, say like on hand rail. I would only shoot for a heavy 1/3 the outside diameter of the pipe. OSHA only requires handrail to be able to withstand a 200-pound impact if memory serves. But whenever doing anything really structural I would shoot for 1/2 the outside diameter of the pipe. But here is how the book says to do it.

pile buck, thanks for the great info. that is why i love this site, lots of very experienced people here...

[ssawyers]

Looks Hot..

Looks to me like overheating the metal. What type joint fit-up? You should try to keep it to a .010 max gap. I know this is tough, but fit-up is one of the biggest factors when welding 4130. What filler/size? sealed pipe? Back purge? It is always difficult to get a straight answer on any 4130 question. Hope this helps. Later Shane Performance Welding & Machine

[bretsk2500]

OSHA only requires handrail to be able to withstand a 200-pound impact if memory serves.

you're 100% correct... I just had to sit through yet another mind-numbing seminar on fall protection. in reality a couple of tacks would be sufficient to meet the 200# spec, which really isn't squat. on the platform I'm working on (very very slowly) I'm using 1x1X0.060 HSS for the rails, plenty strong for the application.

[corn]

It is sealed no back purge, i am using 1/16 filler. I did run 2 passes on the spindle arms that is why the bead is so wide.

[chris2626]

Looks a bit hot to me. It should hold up fine though.

Although others will disagree with me, I will NEVER reccomend using 1/16" tungsten, unless you're welding under a microscope or something like that.

I agree I think it's to HOT a friend of mine loves to run it super hot. I am still learning but seems like when i have it running a Gold or Silver color the heat is just right but I'm no expert. Engloid is the expert.

Chris