[Alan.m]

Hi guys just looking for a bit of advice on tig welding some 2.77mm thick ss sch10 304 having a bit of trouble finding a good setting and the outside weld always come out a little grey? i understand my it might be my angles but if anyone has any suggestions that would be great. Im using 1/16" gold band, 1/16" 308 Filler.
So this was welded with argon along with argon back purge. settings are 0.7 pre flow, 60 amps, 2.5 down slope, 4.5 post flow. It has around 60% penertration i know my welds are not straight but my main issue is the grey colour and if i go any higher amps it just undercuts?



I tried again but with pulse settings are 0.7 pre flow, 45 main amps, 65%, 5.0hz, 75 pulse amps, 2.5 down slope and 4.5 post. again i know my form is very bad but the colour just seems so dull witch i thought was due to heat but i didnt get any penetration when on these settings?



Does anyone have any suggestions? as i can run a nice bead with penertration and amazing colours on 2mm stainless but i move onto this stuff and it all goes down hill?

Cheers Alan

[Poland308]

Most sch 10 pipe welded for full penetration requires an open root.

[Alan.m]

Most sch 10 pipe welded for full penetration requires an open root.

thanks for you comment.
So with an open root would the finish of weld be completely different? what size root would you suggest?

[Poland308]

Bevel the edge down to a knife edge. I like a gap about 1/16 and I run a root with 3/32 rod. Play with the amps and the travel speed. Your probably close. The color in your pics doesn't look to far off.

[Alan.m]

Bevel the edge down to a knife edge. I like a gap about 1/16 and I run a root with 3/32 rod. Play with the amps and the travel speed. Your probably close. The color in your pics doesn't look to far off.

Ok some of the joins have bevels so i will see if i can give a gap and try again, i think im close just wanted to see if there was anything else that i could improve to get it a little better

[GreinTime]

The biggest issue with turning your heat down on any metal, but especially on stainless, is that you typically build up more heat in the part because you are waiting longer for a puddle to form, and it is especially sluggish once moving. Once you have your technique down as far as the angles and everything go, turn the heat up and speed up to account for the difference.

Colin and Alex (ToxicFab and BPAutoSports, respectively) and all the guys you see welding on Instagram have welded hundreds and hundreds of manifolds, so their tubing joints range in the thousands to tens of thousands. You'd have to go back a ways to find it, but Colin did a video of him welding in real time on Instagram, and while you can't see much in the ways of the puddle like you can with Jody's videos, you can see how quickly he is moving about.

Sent from my SM-G900V using Tapatalk

[Markus]

Bevel the pipe to knife as already recommended and for thickness of 2.8 mm I would run two beads.
Another way is that you use argon-hydrogen mix shielding gas. Deeper penetration and also leaves better color.

Why do you need better color? Even orbital will create dark welds in this kind of case and there is nothing wrong with it. Your corrosion recistance has dropped a lot even if the color is pink or so.

[Rick_H]

I personally would weld hotter, and go up to a 3/32" tungsten, with a #8 or #10 cup. With a knife edge and no gap you can achieve 100% penetration bit a small gap will make it easier. Hot and fast with a laywire technique. I've also done sch 10 without filler.100% pen.

Don't get caught up on exterior color...brush it and pickle it of needed.

Fwiw- I weld stainless everyday, so I like to think I know it well and I do tend to weld faster because of it. I'm saying 75-100 amps.

[Otto Nobedder]

I'm with Rick H on this...

First, hotter/faster is better, as total heat input is lower.

Second, the color in the pictures is fine. A clean (never used on anything else, or you'll regret it later) stainless wire brush will make that shiny as new. You have not overheated 304 unless you can't brush out a grey line beside the weld ( each side), and since it's exhaust, even that damage is mostly cosmetic.

I weld sch. 10 304 very frequently as well, sometimes in critical and even coded applications, and I simply do not have cups large enough to keep rainbow colors. They still pass (sometimes very strict) QC. (Most of the time... nobody's perfect... )

Steve S