suck back on root pass of tig weld

what is the trick to crown the bottom of an open butt tig pipe weld? I have no problem getting an excellent root but flat is the best crown I can attain. More heat widens the root and causes the concavity... less heat doesn't seem to fuse


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tungsten angle should be as straight it as possible

side to side wiggle should be kept to minimum

this is where freehanding can be better than walking the cup because you can move forward and back instead of side to side make the root drive home instead of fan out.

jody--weldingtipsandtricks.com

anyone else wanna weigh in?

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suck back on root pass of tig weld

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Jul 29, 2011
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starstarstarstarstar 		walking cup better stainless root
by: Tim


I think someone with freehand is better
but this is not true.

if u do free hand stainless, most likely flat root followed by sucking hotpass, stay longer to make 2mm root inside means u have grey color on inside followed by distortion of pipe.

Also, your welding speed is very slow, so u could be sacked by company.

make 4mm gap, better to be 5mm on top, 35 degree vevel angle, 3 plates on tacking evenly, amps 65 - 75 based on 3" and shedule 80.

i see a lot of comments on gap from this website.
i do not think you guys do not understand the stainless welding. 2mm, 3mm do not work unless using 1.6mm wire. in reality, 2,4mm wire mostly using for speed.

start with cutting wire half. weling from bottom
minimise side to side. just wiggle put wire little deeper and put little bit on lefe side to avoid sticking wire to the puddle.

thanks

u have to see building roots from the top.






Feb 04, 2011
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starstarstarstarstar 		5g-tig root question
by: Anonymous

I am a welding student, working on steel pipe 1/8 root-5g-3/32 rod and tungsten. When i am tigging in some sections of my weld on the inside of the pipe, my weld is a little less than flush with the walls of the pipe, what am i doing wrong and how do i fix it?
Oct 28, 2010
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starstarstarstarstar 		tig root on open butt pipe
by: shapes

this applies to all tig roots on open butts from sch 10 upwards:
after tacking the pipe with 3- 4 decent 1" runs ensure that you have enough gap to put your filler wire completely inside the joint all around.
when on the bottom keep your wire completely on the inside of the landing edge (inside the pipe) from at least 5 `0 clock to 7 0` clock. (5g/6g posn)
as you come up the sides keep half of the wire inside the landing edge and when you are going across the top keep the wire completely outside the landing edge in the prep.
keep your landing edge the same as your filler wire dia and keep a constant flow of wire going in.
you will have to try a few to get used to it but works great once you get going. peace :-)

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