Is this something that is used I the UK?
I doubt of that , as they weld from right to left in UK
Only if your left handed but seeing as the video is showing a weld in 6G position you will always weld it upwards unless you are stoving it.
Is there an advantage in widening the root gap ?
You set the root gap in accordance with what you are welding, the gap on the video is what I would expect to see
Thank you, so it depend of material and material thickness, make sense , but I was not aware of that .
Not in stainless no. You need minimal gap to ensure good root pen and no more. Hang around too long bridging bigger gaps and it will pull and twist. I’ve never 5/6G a stainless pipe before but I know the nature of the material all too well.
You're right in what you say Richard but when MMA welding stainless you need to ensure there is no danger of the root closing too much, with TIG you can generally get away with it but with MMA there is always a danger of flooding the root with slag. Just a personal preference
If the goal is to have all the slag backside I understand that having some space is comfortable.
Stainless is loving more than steel?
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