Asking for info on welding stainless steel pipe

[whm_fab]

from the first photo it doesnt look like you bevelled the pipe? when tig welding shedule pipe like that for manifolds that you want to hit in one pass, its going to be very hard to get full pentration without cooking the material unless you are very experienced and can run super hot and fast and get in and out of the heat as needed without bevelling the pipe.
firstly, 1.6mm tungsten is too small really for the job, you need to be at 2.4 with a good graduated point.

its hard to recommend you where to go next, becuase what i want to advise you on could mess you up until you get it right, but you are running way too little amperage for that.
the problem is just telling you to up the amps could mess you up without knowing what to do with it.

when im doing them im normally running the machine around 175a with the foot pedal rolling in and out of the amperage myself but im fairly motoring along at that amps.

best thing to do is cut a load of spare schedule pipe at the same angle without wasting a flange and try it!

 

[Sam0117]

from the first photo it doesnt look like you bevelled the pipe? when tig welding shedule pipe like that for manifolds that you want to hit in one pass, its going to be very hard to get full pentration without cooking the material unless you are very experienced and can run super hot and fast and get in and out of the heat as needed without bevelling the pipe.
firstly, 1.6mm tungsten is too small really for the job, you need to be at 2.4 with a good graduated point.

its hard to recommend you where to go next, becuase what i want to advise you on could mess you up until you get it right, but you are running way too little amperage for that.
the problem is just telling you to up the amps could mess you up without knowing what to do with it.

when im doing them im normally running the machine around 175a with the foot pedal rolling in and out of the amperage myself but im fairly motoring along at that amps.

best thing to do is cut a load of spare schedule pipe at the same angle without wasting a flange and try it!

thanks for your input I was wondering weather or not to beval the edges, I did on one of the runs to see if it made a difference and at the time I couldn’t really tell, but I think your right going for a 2.4mm tungsten would be better, I think I just need more time under the hood and get a better feel for it, like you say try a few a without a flange and just keep practising Gotta do the runners next and they’ll all have a good bevel on them so I’ll see how they go aswell Thanks again for your input @whm_fab always take on advice And you do it at 170 amps on the pedal I’m hoping I can get that confidant with it soon enough

 

[whm_fab]

cool no problem, you're definitely on the right road! try upping the amps with a bigger tungsten, but you'll have to move faster proportionally.

As always, theres no replacement for time and practice, you'll get there. dont be afraid to try things no matter how odd it might feel to see what happens (on scrap of course!)

Bevelling will make the whole thing a hell of alot easier though

 

[Munkul]

Nice start to the job 1.6mm filler wire and two passes on 3mm (sch10 pipe I presume) is what I would do, in fact what i HAVE done in the past, worked really well. I was taught from our pipe welders when I first learned to TIG weld specifically just to make my first turbo manifold in S/S pipe.

I also started with the collector like you did.
I made up a jig to hold the two flanges, tacked up every piece up, and welded as much as possible whilst bolted to the jig. Then had the flanges machined flat.

Yes to purging, you always place the purge line at the bottom and allow it to vent air out of the top.

As said, colour isn't really an issue as long as its not black... You want to be assured of plenty penetration.

 

[zeppelin builder]

Nice start to the job 1.6mm filler wire and two passes on 3mm (sch10 pipe I presume) is what I would do, in fact what i HAVE done in the past, worked really well. I was taught from our pipe welders when I first learned to TIG weld specifically just to make my first turbo manifold in S/S pipe.

I also started with the collector like you did.
I made up a jig to hold the two flanges, tacked up every piece up, and welded as much as possible whilst bolted to the jig. Then had the flanges machined flat.

Yes to purging, you always place the purge line at the bottom and allow it to vent air out of the top.

As said, colour isn't really an issue as long as its not black... You want to be assured of plenty penetration.

i would give the sharp edges inside a wee fuse together that will help penetration wise and prevent burning , if you want to preserve that razor edge build it up with weld and profile with an internal grinding burr
a full pen set up would be totaly different with reverse preps ie a square edge in some areas

 

[Brad93]

A lot of guys weld them inside and out either with a gas lens and a tonne of stick out or a little WP24

 

[whm_fab]

A lot of guys weld them inside and out either with a gas lens and a tonne of stick out or a little WP24

i weld inside out on the collectors i do but they're all thin wall SS. never actually tried it on schedule pipebut id imagine you'd burn alot of the profile away trying to get penetration from the inside out