Tig welding tips, questions, equipment, applications, instructions, techniques, tig welding machines, troubleshooting tig welding process
nathan
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I got my HTP flowmeter and gas hose in today (review coming soon, but I ordered it Monday, shipping was free, and the reg, hose, and 2# of er70s6 was just under $70, so I'm a happy customer going into it). Filler rod shipped separately and will be here later.

Some of you know, but I will explain again what I'm doing.

I have a few years experience now, but I always want to be making progress, so I'm wanting to learn to TIG pipe. I started my shop with the goal of using it to fund my self-training, and I now have my complete at-home TIG rig. Now I am looking for a place to start.

You guys that do this stuff, and have learned it, where do you recommend that I start? I've done plenty of TIG, up to 5F position ally, so I know what I'm doing, but pipe is a different game, I hear.

Here's my rig:
2012 Lincoln AC/DC 225/125
WP17FV-12R torch with 3/32" 2% thoriated tungsten, power block, and #8 standard cup
HTP flowmeter on an 80cf tank of pure Argon

Where do I need to start if I want to start welding pipe? I intend to go to the scrap yard and get some scrap pipe, what sizes should I look for and what thicknesses? What positions should I start with? Any pointers on those positions?

I am shooting for a 6G unlimited thickness cert, again, self-funded.
Instagram: @nathanppiatt

Owner/welder at Homegrown Metal Fab

Lincoln Weld-Pak 125 HD
Lincoln AC/DC 225/125
Lincoln Port-a-torch
30" 40 ton homegrown press brake
Northern Industrial1HP 3/4" chuck, 16 speed drill press
Poland308
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Start with good fit up. I.E. Bevel the end and then give the pipe a bit of land you don't want to start with a knife edge it's to easy to burn a hole starting a root. If your going to start with 3/32 rod give yourself a gap just smaller than your rod thickness. Try starting on a thicker wall pipe if you can sch 80 or thicker. It will give you a more forgiving heat sink for your first few root passes. Try a larger diameter pipe 6 in and above. That will allow you to learn how to move around the pipe as you go small pipe means you have to move faster ( body motion). And start in a 2 g position that will make your tack up easier. If you start a joint take the time to weld it all the way out root to cover. Let the pipe cool between passes. There is an inter pass temp on carbon pipe. Rule of thumb to start the pipe should be cool enough to touch it with a gloved hand and not get burned. Grind out your tacks as you come to them don't try to burn through. Don't be afraid to grind down your start and stop points it will help you to catch if you have porosity and it will give you a good clean even spot for a tie in on beads.
I have more questions than answers

Josh
nathan
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Thanks a lot, man! Now I know where to start :) I will be sure and post updates on this thread, to include pictures. For now, here's my rig.
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IMG_20151001_221241769.jpg
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Instagram: @nathanppiatt

Owner/welder at Homegrown Metal Fab

Lincoln Weld-Pak 125 HD
Lincoln AC/DC 225/125
Lincoln Port-a-torch
30" 40 ton homegrown press brake
Northern Industrial1HP 3/4" chuck, 16 speed drill press
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Nathan,
You'll be pretty much maxed out on your machine for schedule 80 pipe. As you progress, move down in pipe size. Smaller is harder as was said. Try and aim the torch towards the center of the pipe as you go, this keeps your torch angle pretty good. Jody has a couple of videos I believe on pipe that will help, pay attention to what he's saying as well as watching how he moves around the pipe.

Len
Now go melt something.
Instagram @lenny_gforce

Len
Rick_H
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I'll add start with 1G and 2G then go 5G and 6G. In the 2G position I suggest also using a 6" sch 40 pipe, you can also practice walking the cup and running beads around the pipe, this will help get the motion down and use all the material.

On sch40 I use a 37.5 degree, 4 tacks at the quadrants 3/32"-1/8" gap, 3/32" filler. Practice both laywire walking and scoot front an back, left handed and right handed. Some test will not allow you to grind or feather tacks, all depends on the WPS... So practice both ways, bmake sure your prep is good, nice shiny metal, brush good between passes and let cool as noted earlier. The root pass will be around 85-95amps, go up about 10 or so for the hot pass then a cover, cover can be stringers or a single wide cap, just don't weave a 3/4" wide bead..lol I used 3/32" tung, #7-8 cup and a gas lens, but a reg lens will work as well, practice both of you can it will prepare you for the field.

Ultimately the cert test will be 2" pipe, 6g and they will make you go top to bottom up each side, so both hands makes it a lot easier. Jody's test pipe videos are spot on. I also recommend a TIG finger, make it easy to prop right on the pipe of your not walking.
I weld stainless, stainless and more stainless...Food Industry, sanitary process piping, vessels, whatever is needed, I like to make stuff.
ASME IX, AWS 17.1, D1.1
Instagram #RNHFAB
Poland308
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For the root I often run around 80 amps for a 3/32 rod but I usually switch to a standard cup # 5 and keep my tungsten really short. If you hold the cup as far down in the grove as you can I leave just enough stick out to almost touch the imaginary top of my gap.
I have more questions than answers

Josh
nathan
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Thanks for the help, y'all! I just ran my first weave bead ever and it is pretty gnarly. I posted it in the "what I welded today" thread, if you wanna go see it. I will be going to the scrap yard Monday to scrounge up some scrap pipe and flat bar for coupons. I hope to try my first root pass sometime early in the week, as soon as I get time. When you start your root, do you start on a tack, or somewhere between them? It makes sense to grind them out right before you get to them, but it seems to me that you wouldn't want to start on a tack. But I'm new to pipe, so I figured I'd ask :)
Instagram: @nathanppiatt

Owner/welder at Homegrown Metal Fab

Lincoln Weld-Pak 125 HD
Lincoln AC/DC 225/125
Lincoln Port-a-torch
30" 40 ton homegrown press brake
Northern Industrial1HP 3/4" chuck, 16 speed drill press
Rick_H
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nathan wrote:Thanks for the help, y'all! I just ran my first weave bead ever and it is pretty gnarly. I posted it in the "what I welded today" thread, if you wanna go see it. I will be going to the scrap yard Monday to scrounge up some scrap pipe and flat bar for coupons. I hope to try my first root pass sometime early in the week, as soon as I get time. When you start your root, do you start on a tack, or somewhere between them? It makes sense to grind them out right before you get to them, but it seems to me that you wouldn't want to start on a tack. But I'm new to pipe, so I figured I'd ask :)

The tacks stay in...

If you are going to "feather" the tacks, you lightly grind them at the start and finish of each tack. I start about 1" before a tack, and weld right over through it, you don't want to stop at a tack or you may not have complete penetration or break the edges down. Some tests let you "feather" or grind, some don't. For instance when I took my ASME IX test, I did not grind, just brush very good in between passes and let it cool. I did make sure I lightly sanded the outside of the pipe next to the bevel on my test coupons to ensure I had clean metal and wouldn't pull anything into my hot pass or cover.

Take this FWIW, but I never weave much...I either dab and go front back like a normal weld, or walk the cup. I typically only walk on pipe 4" and larger.
I weld stainless, stainless and more stainless...Food Industry, sanitary process piping, vessels, whatever is needed, I like to make stuff.
ASME IX, AWS 17.1, D1.1
Instagram #RNHFAB
nathan
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Is weaving different than walking the cup? I walked the cup on that weld, I thought the resulting bead was called a weave, whether you walk it or freehand it.
Instagram: @nathanppiatt

Owner/welder at Homegrown Metal Fab

Lincoln Weld-Pak 125 HD
Lincoln AC/DC 225/125
Lincoln Port-a-torch
30" 40 ton homegrown press brake
Northern Industrial1HP 3/4" chuck, 16 speed drill press
Poland308
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Rick is right I said grind out a tack on my earlier post but meant grind thin or feather them I do the same thing to the end of a weld. Then I restart my arc and get the puddle started on top of the weld as you move back down into the grove this helps make sure you brake down the edges on the root. If you look at the back side of a root pass and you can still see the edge of the metal were you ground the pipe or what looks like under cut than your not getting full penetration.
I have more questions than answers

Josh
Poland308
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Walking the cup is just a weave pattern developed from resting the cup against the pipe as you weave. If the cup stays against the sides of your bevel than it helps steady your movements as you travel. It's just a technique not necessarily a better process. It does help build good muscle memory for when your out of position.
Some weld processes call for not letting the cup touch the pipe at all.
I have more questions than answers

Josh
nathan
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Update:

Went to the scrap yard today. Took my boy out and he had a great time stomping puddles and asking what each and every thing was lol. They had some 7", 8", and some 4" heavy wall, but no 6". It was all $6-$7/ foot!!! Wow, mucho expensive. So I got some 2-5/16" OD 1/4" wall that was ten bucks for nine feet. It still has the mill scale and the original writing on it. It was the best stick in the pile. But that heavy wall was some sexy steel. I want to try that lol

I ordered some cutting, grinding, and flap discs from Empire Abrasives yesterday that will be here tomorrow, and I will cut up some 3" long coupons to start practicing. I've been practicing walking the cup on vertical fillets for now and am somewhat pleased with my progress. I'm excited to be making progress like this. Stagnation frustrates the piss outta me.
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The only pic I have. They are looking better now.
The only pic I have. They are looking better now.
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Instagram: @nathanppiatt

Owner/welder at Homegrown Metal Fab

Lincoln Weld-Pak 125 HD
Lincoln AC/DC 225/125
Lincoln Port-a-torch
30" 40 ton homegrown press brake
Northern Industrial1HP 3/4" chuck, 16 speed drill press
nathan
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I'm posting updates here to ask for advice and so that I can keep notes for myself as well.

Got my first ever pipe root made. Same pipe I mentioned in the last post. I need to make a testing stand.

I beveled it out with about a 1/16" gap. I think that's 1.6mm for our metric-minded friends. Wasn't perfect fit up, and about a 3/32" land, which was entirely too much. Just under half the material thickness.

Ran at 85A, which was too cold for that size land. The root got decent penetration, but no reinforcement, I'm sure it wouldn't pass any legitimate test.

I'm including pictures for anyone interested, logging my progress.

I need some hand steadiness exercises, this was done free hand, with no props, and I never knew I was this shaky lol.

My next fit up will have more effort put into keeping the pipes aligned better. My land on these is about 1/32", and I will keep the gap about 1/16". Maybe bump the amps to 95, we shall see.

I see why everyone suggested bigger pipe, this small stuff went pretty quick with not a lot of time for paying attention to angles and such, so I will see if I can scrounge up enough dough for 4-5' of 5 or 6 inch pipe. Probably somewhere around $20-30 from the scrap yard.

It looks like this stuff will take about three passes to finish out once I get my root to lay in good. I still have about 8'4" of this pipe left, so plenty of 2" coupons :) I hope to run at least one pass every night after work. Gonna cut bunches and bunches of coupons here, maybe even work on some stick pipe! This is exciting.
Attachments
Second coupon set
Second coupon set
IMG_20151101_160526449.jpg (43.49 KiB) Viewed 794 times
Outside root
Outside root
IMG_20151101_160506321.jpg (55.88 KiB) Viewed 794 times
Inside root
Inside root
IMG_20151101_161253563.jpg (44.29 KiB) Viewed 794 times
Instagram: @nathanppiatt

Owner/welder at Homegrown Metal Fab

Lincoln Weld-Pak 125 HD
Lincoln AC/DC 225/125
Lincoln Port-a-torch
30" 40 ton homegrown press brake
Northern Industrial1HP 3/4" chuck, 16 speed drill press
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